tag:theconversation.com,2011:/au/topics/animal-communication-13608/articlesAnimal communication – The Conversation2024-01-16T21:51:20Ztag:theconversation.com,2011:article/2208042024-01-16T21:51:20Z2024-01-16T21:51:20ZFowl language: AI is learning to analyze chicken communications to help us understand what all the clucking’s about<figure><img src="https://images.theconversation.com/files/569623/original/file-20240116-21-fbzgp8.jpg?ixlib=rb-1.1.0&rect=0%2C17%2C6000%2C3970&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Chickens are vibrant communicators.</span> <span class="attribution"><span class="source">(Shutterstock)</span></span></figcaption></figure><p>Have you ever wondered what chickens are talking about? Chickens are quite the communicators — their clucks, squawks and purrs are not just random sounds but a complex language system. These sounds are their way of interacting with the world and expressing joy, fear and social cues to one another. </p>
<p>Like humans, the “language” of chickens varies with age, environment and surprisingly, <a href="https://doi.org/10.1371/journal.pone.0010639">domestication</a>, giving us insights into their <a href="https://doi.org/10.3390/ani11020434">social structures</a> and behaviours. Understanding these vocalizations can transform our approach to poultry farming, enhancing chicken welfare and quality of life.</p>
<p>Our research at Dalhousie University applies artificial intelligence (AI) to decode the language of chickens. It’s a project that’s set to revolutionize our understanding of these feathered creatures and their communication methods, offering a window into their world that was previously closed to us.</p>
<h2>Chicken translator</h2>
<p>The use of AI and machine learning in this endeavor is like having a universal translator for chicken speech. AI can analyze vast amounts of audio data. As our research, yet to be peer-reviewed, is documenting, our algorithms are learning to recognize patterns and nuances in <a href="https://doi.org/10.1101/2023.12.26.573338">chicken vocalizations</a>. This isn’t a simple task — chickens have a range of sounds that vary in pitch, tone, and context. </p>
<p>But by using advanced data analysis techniques, we’re beginning to crack their code. This breakthrough in animal communication is not just a scientific achievement; it’s a step towards more humane and empathetic treatment of farm animals.</p>
<p>One of the most exciting aspects of this research is understanding the emotional content behind these sounds. Using Natural Language Processing (NLP), a technology often used to decipher human languages, we’re learning to interpret the <a href="https://doi.org/10.3390/s21020553">emotional states of chickens</a>. Are they stressed? Are they content? By understanding their <a href="https://doi.org/10.3390/ani12060759">emotional state</a>, we can make more informed decisions about their care and environment.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/569656/original/file-20240116-23-oqw734.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="a person in a white hazmat suit holding an ipad while surrounded by chickens" src="https://images.theconversation.com/files/569656/original/file-20240116-23-oqw734.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/569656/original/file-20240116-23-oqw734.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/569656/original/file-20240116-23-oqw734.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/569656/original/file-20240116-23-oqw734.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/569656/original/file-20240116-23-oqw734.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/569656/original/file-20240116-23-oqw734.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/569656/original/file-20240116-23-oqw734.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Understanding how chickens express themselves will impact how they are farmed.</span>
<span class="attribution"><span class="source">(Shutterstock)</span></span>
</figcaption>
</figure>
<h2>Non-verbal chicken communication</h2>
<p>In addition to vocalizations, our research also delves into non-verbal cues to gauge emotions in chickens. Our research has also explored chickens’ eye blinks and facial temperatures. How these might be <a href="https://doi.org/10.1101/2022.01.31.478468">reliable indicators</a> of chickens’ emotional states is examined in a preprint (not yet peer reviewed) paper.</p>
<p>By using non-invasive methods like video and thermal imaging, we’ve observed changes in temperature around the eye and head regions, as well as variations in blinking behaviour, which appear to be responses to stress. These preliminary findings are opening new avenues in understanding how chickens express their feelings, both behaviourally and physiologically, providing us with additional tools to assess their well-being.</p>
<h2>Happier fowl</h2>
<p>This project isn’t just about academic curiosity; it has <a href="https://doi.org/10.1101/2022.07.31.502171">real-world implications</a>. In the agricultural sector, understanding chicken vocalizations can lead to improved farming practices. Farmers can use this knowledge to create better living conditions, leading to healthier and happier chickens. This, in turn, can impact the quality of produce, animal health and overall farm efficiency. </p>
<p>The insights gained from this research can also be applied to other areas of <a href="https://doi.org/10.1016/j.measurement.2022.110819">animal husbandry</a>, potentially leading to breakthroughs in the way we interact with and care for a variety of farm animals.</p>
<p>But our research goes beyond just farming practices. It has the potential to influence policies on animal welfare and ethical treatment. As we grow to understand these animals better, we’re compelled to <a href="https://doi.org/10.3390/agriengineering5010032">advocate for their well-being</a>. This research is reshaping how we view our relationship with animals, emphasizing empathy and understanding.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/569662/original/file-20240116-15-c9v7e6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="a man reaches into a chicken coop filled with chicken" src="https://images.theconversation.com/files/569662/original/file-20240116-15-c9v7e6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/569662/original/file-20240116-15-c9v7e6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=401&fit=crop&dpr=1 600w, https://images.theconversation.com/files/569662/original/file-20240116-15-c9v7e6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=401&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/569662/original/file-20240116-15-c9v7e6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=401&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/569662/original/file-20240116-15-c9v7e6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/569662/original/file-20240116-15-c9v7e6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/569662/original/file-20240116-15-c9v7e6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Understanding animal communication and behaviour can impact animal welfare policies.</span>
<span class="attribution"><span class="source">(Unsplash/Zoe Schaeffer)</span></span>
</figcaption>
</figure>
<h2>Ethical AI</h2>
<p>The ethical use of AI in this context sets a precedent for future technological applications in animal science. We’re demonstrating that technology can and should be used for the <a href="https://doi.org/10.1007/s44230-023-00050-2">betterment of all living beings</a>. It’s a responsibility that we take seriously, ensuring that our advancements in AI are aligned with ethical principles and the welfare of the subjects of our study.</p>
<p>The implications of our research extend to education and conservation efforts as well. By understanding the communication methods of chickens, we gain insights into avian communication in general, providing a unique perspective on the complexity of animal communication systems. This knowledge can be vital for conservationists working to protect bird species and their habitats.</p>
<p>As we continue to make strides in this field, we are opening doors to a new era in <a href="https://doi.org/10.3389/fvets.2021.740253">animal-human interaction</a>. Our journey into <a href="https://doi.org/10.20944/preprints202309.1714.v1">decoding chicken language</a> is more than just an academic pursuit: it’s a step towards a more empathetic and responsible world. </p>
<p>By leveraging AI, we’re not only unlocking the secrets of avian communication but also setting new standards for animal welfare and ethical technological use. It’s an exciting time, as we stand on the cusp of a new understanding between humans and the animal world, all starting with the chicken.</p><img src="https://counter.theconversation.com/content/220804/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Suresh Neethirajan does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Artificial intelligence can process large amounts of chicken vocalizations, identifying patterns in the birds’ communications.Suresh Neethirajan, University Research Chair in Digital Livestock Farming, Dalhousie UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2198072023-12-18T19:09:26Z2023-12-18T19:09:26ZDo dog ‘talking buttons’ actually work? Does my dog understand me? Here’s what the science says<figure><img src="https://images.theconversation.com/files/566241/original/file-20231218-26-xks3j4.jpg?ixlib=rb-1.1.0&rect=38%2C54%2C5134%2C3389&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>Is your dog bothered by something but you can’t work out what? Do you wish they could tell you?</p>
<p>There’s a <a href="https://www.bestproductsaustralia.com/best-dog-talking-buttons?targetid=dsa-469483434121&matchtype=&device=c&campaignid=18074730918&creative=617050046549&adgroupid=143033333449&feeditemid=94269287247&loc_physical_ms=9070871&loc_interest_ms=&network=g&devicemodel=&placement=&keyword=$&target=&aceid=&adposition=&trackid=au_all_top_1_1&mId=407-132-4411&trackOld=true&gad_source=1&gclid=Cj0KCQiAsvWrBhC0ARIsAO4E6f_1-Amk1AXOLSVbsEPQYiZU5mviL8Q0wWoDhotFyeyRz8hwcIWjv-QaAk--EALw_wcB">huge range</a> of dog “talking” buttons on the market that now claim to let your dog do this. A very basic kit will set you back about $15, while more sophisticated ones can cost hundreds of dollars.</p>
<p>But is there any evidence these products work? </p>
<h2>How the buttons work</h2>
<p>The idea behind these buttons is simple. You record yourself speaking a word such as “treat” or “outside” into each button, after which the word is played back each time the button is pressed. Your dog can supposedly be trained to understand the words coming from the buttons, and use them to communicate with you. </p>
<p>Talking buttons are an example of <a href="https://www.speechpathologyaustralia.org.au/Communication_Hub/Resources/Fact_Sheets/Augmentative-and-Alternative-Communication.aspx#:%7E:text=Types%20of%20AAC&text=These%20include%3A,phones%20to%20help%20you%20communicate">augmentative and alternative communication</a>. To put it simply, they’re a method of communication that doesn’t use speech. In humans, similar devices are valuable for people with autism or intellectual disability, or those suffering from a stroke or other neurological condition. </p>
<h2>Can dogs learn complex communication?</h2>
<p>A dog <a href="https://youtu.be/2qkEyvzcVkc?si=ac1iWCGxfjRrjmx_">could figure out</a> to press talking buttons through a process called <a href="https://thedecisionlab.com/reference-guide/management/reinforcement-theory">operant conditioning</a> – the same process used to teach dogs simple commands such as “sit”. When a dog performs a behaviour and receives something they want, such as a treat, they’re more likely to continue that behaviour.</p>
<p>The idea of dogs “talking” to humans with buttons was started by Christina Hunger, a speech language pathologist who understood the use of augmentative and alternative communication devices. Hunger claims to have taught her dog Stella more than 50 words and phrases <a href="https://www.hungerforwords.com/">up to five-words long</a>.</p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/anxious-dogs-have-different-brains-to-normal-dogs-brain-scan-study-reveals-201775">Anxious dogs have different brains to normal dogs, brain scan study reveals</a>
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<h2>Alternative explanations</h2>
<p>There are simple explanations for what may seem like complex behaviour in animals. For one thing, animals excel in picking up our body language. As a result, they may appear to understand more than they actually do. </p>
<p><a href="https://en.wikipedia.org/wiki/Clever_Hans">Clever Hans the horse</a> is the perfect example. Hans <a href="https://archive.nytimes.com/www.nytimes.com/books/first/d/dehaene-number.html.">gained prominence</a> in the early 1900s for allegedly being able to do mathematics. Even his trainer believed he could count. It was only when the trainer was no longer present that people realised Hans was relying on involuntary cues in the trainer’s body language to “solve” problems, and couldn’t actually count. </p>
<p>Dogs are probably even better than horses at picking up on our body language cues. As the first <a href="https://www.frontiersin.org/articles/10.3389/fevo.2020.00103/full#:%7E:text=Dogs%20were%20the%20first%20animal,origins%20and%20events%20of%20domestication.">domesticated species</a>, they’ve spent thousands of years working out what we’re likely to do next. Just think of all the times your dog has rushed to the door even before you’ve picked up their leash.</p>
<p>When we train dogs to use talking buttons, they’re probably learning using operant conditioning to some extent. For example, they learn that pressing a button can lead to a reward. </p>
<p>But in cases where dogs seem to be able to string multiple buttons together to say something advanced, or where they can press the “right” button when asked, they’re likely just responding to their owner’s body language. And they probably wouldn’t be able to replicate the behaviour if a new pet-sitter was making the command. </p>
<p><div data-react-class="TiktokEmbed" data-react-props="{"url":"https://www.tiktok.com/@whataboutbunny/video/7305801384241138986?is_from_webapp=1\u0026sender_device=pc\u0026web_id=7247360749801375234"}"></div></p>
<h2>We need more data</h2>
<p>Federico Rossan, director of the Comparative Cognition Lab at UC San Diego, is working on a <a href="https://www.theycantalk.org/research">large project analysing results</a> from dogs using talking buttons. </p>
<p>Although <a href="https://fluent.pet/">FluentPet</a> (a business that sells pet communication products) is involved, the study is reported to be independent. That means a person who doesn’t have a conflict of interest will analyse and report the results.</p>
<p>Data collection started in late 2020, but so far no evidence has been published. Until then, the best “evidence” we have for these products is anecdotal reporting coming from dog owners who are probably biased (since they’d like to think their dog is very clever). </p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/if-humans-disappeared-what-would-happen-to-our-dogs-218703">If humans disappeared, what would happen to our dogs?</a>
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</em>
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<h2>Could it do any harm?</h2>
<p>It matters when we treat our dogs differently depending on what <em>we</em> think <em>they</em> are thinking.</p>
<p>One example is when we assume dogs feel guilty for certain actions. For instance, when you come home and your dog has chewed up your favourite rug, they might look “guilty” as you scold them, but they’re actually just responding to your reaction. Studies have shown dogs can’t experience the <a href="https://www.abc.net.au/news/2015-08-23/dog-shaming-falls-on-deaf-ears-for-canines/6715932">human emotion of guilt</a>.</p>
<p>That’s why you shouldn’t punish your dog when you come home to a chewed-up carpet. They won’t associate your yelling or smacking with their action from hours earlier. </p>
<p>The reality is some dogs will simply be more interested in interacting with talking buttons than others. There’s no good reason to think these dogs are therefore smarter than others.</p>
<p><div data-react-class="TiktokEmbed" data-react-props="{"url":"https://www.tiktok.com/@lyndibuttons/video/7079788076142234885?lang=en\u0026q=dog%20talking%20buttons\u0026t=1702878026732"}"></div></p>
<h2>Should I buy talking buttons?</h2>
<p>If you can recognise and account for the potential risks mentioned above, then buying talking buttons won’t do any harm to you or your dog (apart from putting a dent in your wallet). </p>
<p>That said, there are myriad ways to communicate with your dog without needing such a device. Chaser the border collie learned how to retrieve 1,022 toys by name without <a href="https://en.wikipedia.org/wiki/Chaser_(dog)">an augmentative device</a>.</p>
<p>However you do it, spending time with your dog using positive reinforcement training will benefit both of you. Dogs are amazing, unique animals with whom we can communicate in all kinds of ways, and they don’t need to understand our language for this.</p>
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<a href="https://images.theconversation.com/files/566243/original/file-20231218-21-2ed1pw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/566243/original/file-20231218-21-2ed1pw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/566243/original/file-20231218-21-2ed1pw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/566243/original/file-20231218-21-2ed1pw.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/566243/original/file-20231218-21-2ed1pw.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/566243/original/file-20231218-21-2ed1pw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/566243/original/file-20231218-21-2ed1pw.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/566243/original/file-20231218-21-2ed1pw.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">Talking buttons could be harmful if a dog’s refusal to use them changes their owner’s attitude towards them.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
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<p><em>Correction: this article previously included a line saying human language is “too complex” for a dog to understand. This has now been removed as it doesn’t correctly reflect the state of research on dog communication.</em></p><img src="https://counter.theconversation.com/content/219807/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Susan Hazel receives funding from the Waltham Foundation and is associated with the Dog & Cat Management Board of South Australia, RSPCA South Australia and Animal Therapies Ltd. </span></em></p><p class="fine-print"><em><span>Eduardo Fernandez receives funding from the Waltham Foundation.</span></em></p>There are simple explanations for what may seem like complex behaviours in dogs.Susan Hazel, Associate Professor, School of Animal and Veterinary Science, University of AdelaideEduardo J Fernandez, Visiting Assistant Professor, Florida Institute of TechnologyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1889562023-03-13T12:26:33Z2023-03-13T12:26:33ZSmell is the crucial sense that holds ant society together, helping the insects recognize, communicate and cooperate with one another<figure><img src="https://images.theconversation.com/files/513805/original/file-20230306-20-apwc3a.jpg?ixlib=rb-1.1.0&rect=0%2C1224%2C2696%2C1582&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Ants from different colonies will fight based on smell alone.</span> <span class="attribution"><span class="source">Joseph Howell, Vanderbilt University</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span></figcaption></figure><p>Ants can be found in <a href="https://doi.org/10.1038/s41467-018-04218-4">nearly every location on Earth</a>, with rough estimates suggesting there are <a href="https://www.bbc.com/news/magazine-29281253">over 10 quadrillion individuals</a> – that is a 1 followed by 16 zeroes, or about 1 million ants per person. Ants are among the most biologically successful animals on the planet. </p>
<p>A surprising part of their evolutionary success is the amazing sense of smell that lets them recognize, communicate and cooperate with one another.</p>
<p>Ants live in complex colonies, sometimes referred to as nests, that are home to <a href="https://wwnorton.com/books/9780393067040">a wide range of social interactions</a>. Here, one or more queens are responsible for all the reproduction within that colony. The vast majority of colony members are female workers – sisters that never mate or reproduce and live only to serve the group.</p>
<p>Ants need to <a href="https://doi.org/10.1186/s12915-022-01505-x">defend their colony</a>, <a href="https://doi.org/10.1371/journal.pone.0052219">seek food</a> and <a href="https://doi.org/10.1086/690840">take care of offspring</a>. To accomplish these tasks some ant species domesticate other insects, while others create agricultural systems, harvesting leaves from which they <a href="https://doi.org/10.1086/661128">grow edible fungal gardens</a>. Successfully coordinating all these intricate tasks requires reliable and secure communication among nestmates.</p>
<p><a href="https://scholar.google.com/citations?user=PrNrnI8AAAAJ&hl=en&oi=sra">We</a> <a href="https://scholar.google.com/citations?hl=en&user=IZUwOQ0AAAAJ">are</a> biologists who study the remarkable sensory abilities of ants. <a href="https://lab.vanderbilt.edu/zwiebel-lab/">Our recent work</a> shows how their societies depend on the exchange of reliable information which, if disrupted, spells doom for their colonies.</p>
<h2>Unique scents</h2>
<p>Human communication relies primarily on verbal and visual cues. We usually identify our friends by the sound of their voice, the appearance of their face or the clothes they wear. Ants, however, <a href="https://doi.org/10.1242/jeb.215400">rely primarily on their acute sense of smell</a>. </p>
<p>An exterior shell, known as an exoskeleton, encases an ant’s body. This greasy coat carries a unique scent that varies from individual to individual and gives each ant a <a href="https://www.hup.harvard.edu/catalog.php?isbn=9780674040755">unique odor signature that other ants can detect</a>. This odor signature can communicate important information. </p>
<p>The queen, for example, will smell slightly different from a worker, and thus receive special treatment within the colony. Importantly, ants from different colonies will smell slightly different from one another. The detection and decoding of these differences is <a href="https://doi.org/10.3389/fnbeh.2018.00191">vital for colony defense</a> and can trigger aggressive turf wars between colonies when ants catch a whiff of intruders.</p>
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<figcaption><span class="caption">Interactions between nestmates are friendly. But when ants sniff out enemy non-nestmates, there is rapid and deadly aggression. Produced by the Zwiebel Lab, Vanderbilt University, filmed by Stephen Ferguson.</span></figcaption>
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<p>For ants and other insects, receiving chemical information begins when an odor enters the small hairs located along their antennae. These hairs are hollow and contain <a href="https://doi.org/10.1016/j.cois.2014.10.006">special receptors, called chemosensory neurons</a>, that sort and send the chemical information to the ant’s brain. </p>
<p>Odors, such as those given off from an ant’s greasy coat, <a href="https://doi.org/10.1242/jeb.215400">act like chemical “keys</a>.” Ants can smell these odor keys only if they are inserted into the correct set of chemosensory neuron “locks.” A neuronal lock remains shut to any odors except its particular key. When the correct key binds to the correct neuronal lock, though, the receptor sends a complex message to the brain. The ant’s brain is able to decode this sensory information to make decisions that ultimately lead to cooperation between nestmates – or battles between non-nestmates. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/514327/original/file-20230308-22-8r9eol.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A Tupperware container filled with ants. Three test tubes with cotton stoppers appear to hold water." src="https://images.theconversation.com/files/514327/original/file-20230308-22-8r9eol.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/514327/original/file-20230308-22-8r9eol.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/514327/original/file-20230308-22-8r9eol.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/514327/original/file-20230308-22-8r9eol.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/514327/original/file-20230308-22-8r9eol.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/514327/original/file-20230308-22-8r9eol.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/514327/original/file-20230308-22-8r9eol.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A colony of carpenter ants (<em>Camponotus floridanus</em>) reared in the Zwiebel Lab at Vanderbilt University.</span>
<span class="attribution"><span class="source">LJ Zwiebel, Vanderbilt University</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>Changing the locks</h2>
<p>To better understand how ants detect and communicate information, we use laboratory tools such as <a href="https://doi.org/10.1242/jeb.215400">precisely targeted drugs</a> and <a href="https://doi.org/10.1016/j.cell.2017.06.051">genetic</a> <a href="https://doi.org/10.1016/j.cell.2017.07.001">engineering</a> to manipulate their sense of smell. We are especially interested in what happens when an ant’s sense of smell goes wrong. </p>
<p>For example, when we prevent an odor “key” from opening a chemosensory “lock,” it prevents the chemical information from reaching the brain. This would be like plugging your nose or standing in a completely dark room – no scents or sights would register. We can also open all the “locks” at the same time, which floods the neurons with too many messages. Both of these scenarios dramatically compromise an ant’s ability to detect and receive accurate information.</p>
<p>When we messed with ants’ sense of smell – whether shutting down or flooding their odor receptors – we found <a href="https://doi.org/10.1242/jeb.215400">they no longer attacked non-nestmates</a>. Instead, they became less aggressive. In the absence of clear information, ants exercised restraint and opted to accept rather than attack their fellow ant. Put another way, ants ask questions first and shoot later. </p>
<p>We believe this social restraint is hard-wired and gives ants an evolutionary advantage. When you live in a colony with tens of thousands of sisters, a simple case of mistaken identity or miscommunication could lead to deadly infighting and societal chaos, which is potentially very costly.</p>
<p>When ants in our experiments lose their sense of smell, and their ability to detect accurate information becomes compromised, <a href="https://doi.org/10.1016/j.cell.2017.06.051">they no longer stick together</a> <a href="https://doi.org/10.1016/j.cell.2017.07.001">in a cohesive colony</a>. </p>
<p>Not only do they fail to recognize and attack foes, they also stop cooperating with their friends. Without nurses to take care of the young or foragers to collect food, the eggs dry up and the queen goes hungry. </p>
<p>We discovered that without an accurate means of communicating and receiving chemical information, ant societies collapse and the colony quickly dies. Miscommunication or the lack of accurate information <a href="https://www.pbs.org/newshour/nation/miscommunication-blamed-deadly-u-s-mistake-afghanistan">affects other highly social animals, including humans</a>, as well. For ants, it all depends on their sense of smell.</p><img src="https://counter.theconversation.com/content/188956/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Laurence Zwiebel currently receives funding from the NIH and Vanderbilt University. </span></em></p><p class="fine-print"><em><span>Stephen Ferguson currently receives funding from the NIH and Vanderbilt University.</span></em></p>Researchers explore what happens when ants can’t properly use smell to detect friend from foe.Laurence Zwiebel, Professor of Biological Sciences and of Pharmacology, Vanderbilt UniversityStephen Ferguson, Postdoctoral Scholar in Biological Sciences, Vanderbilt UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2008962023-03-09T19:02:52Z2023-03-09T19:02:52ZUnlocking secrets of the honeybee dance language – bees learn and culturally transmit their communication skills<figure><img src="https://images.theconversation.com/files/514032/original/file-20230307-14-lrvmni.jpg?ixlib=rb-1.1.0&rect=107%2C151%2C1698%2C1222&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A honeybee is performing the waggle dance in the center of this photo to communicate the location of a rich nectar source to its nestmates.</span> <span class="attribution"><span class="source">Heather Broccard-Bell</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span></figcaption></figure><p>The Greek historian Herodotus reported over 2,000 years ago on a misguided <a href="https://www.youtube.com/watch?v=Lr0qOvaABms">forbidden experiment</a> in which two children were prevented from hearing human speech so that a king could discover the true, unlearned language of human beings.</p>
<p>Scientists now know that human language requires <a href="https://doi.org/10.1016/j.dr.2005.11.002">social learning and interaction with other people</a>, a property shared with multiple <a href="https://press.uchicago.edu/ucp/books/book/chicago/S/bo5561640.html">animal languages</a>. But why should humans and other animals need to learn a language instead of being born with this knowledge, like many other <a href="https://doi.org/10.1098/rstb.2019.0054">animal species</a>? </p>
<p>This question fascinates <a href="https://labs.biology.ucsd.edu/nieh/">me and my colleagues</a> and is the basis for our recent <a href="https://www.science.org/doi/10.1126/science.ade1702">paper published in the journal Science</a>. As a <a href="https://scholar.google.com/citations?hl=en&view_op=list_works&authuser=1&gmla=AJsN-F7wX8BidJ6TwElz9ImT2RbNwpW3_-QAtnkg4bRCfGzWx_QeD5PZ6XYzjRz583sZ7QwpH7pvZcQ-aC2sw-_gMzAsfsnA8Q&user=EA1s3KkAAAAJ">biologist</a>, I have spent decades studying honeybee communication and how it may have evolved.</p>
<p>There are two common answers to why language should be learned or innate. For one, complex languages can often respond to local conditions as they are learned. A second answer is that complex communication is often difficult to produce even when individuals are born with some knowledge of the correct signals. Given that the ways honeybees communicate are quite elaborate, we decided to study how they learn these behaviors to answer this language question.</p>
<h2>What is a waggle dance?</h2>
<p>Astonishingly, honeybees possess one of the most complicated examples of nonhuman communication. They can tell each other where to find resources such as food, water, or nest sites with a physical “waggle dance.” This dance conveys the <a href="https://doi.org/10.1146/annurev.ento.47.091201.145306">direction, distance and quality</a> of a resource to the bee’s nestmates.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/aUCoLeI5Qxg?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">This video, from PBS Nova, shows bees getting their “waggle dance” on.</span></figcaption>
</figure>
<p>Essentially, the dancer points recruits in the correct direction and tells them how far to go by repeatedly circling around in a figure eight pattern centered around a waggle run, in which the bee <a href="https://doi.org/10.1146/annurev.ento.47.091201.145306">waggles its abdomen as it moves forward</a>. Dancers are pursued by potential recruits, bees that <a href="https://www.youtube.com/watch?v=k9m8B40-p6k">closely follow the dancer</a>, to learn where to go to find the communicated resource.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/513856/original/file-20230307-20-xqlq9k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Many bees crammed together, with white arrows pointing to the waggle dancer and the dance follower bees." src="https://images.theconversation.com/files/513856/original/file-20230307-20-xqlq9k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/513856/original/file-20230307-20-xqlq9k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/513856/original/file-20230307-20-xqlq9k.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/513856/original/file-20230307-20-xqlq9k.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/513856/original/file-20230307-20-xqlq9k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=565&fit=crop&dpr=1 754w, https://images.theconversation.com/files/513856/original/file-20230307-20-xqlq9k.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=565&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/513856/original/file-20230307-20-xqlq9k.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=565&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The waggle dancer gives the instructions, and the followers learn where they can find the indicated resource.</span>
<span class="attribution"><span class="source">Dong Shihao</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Longer waggle runs communicate greater distances, and the waggle angle communicates direction. For higher-quality resources such as sweeter nectar, dancers <a href="https://doi.org/10.1146/annurev.ento.47.091201.145306">repeat the waggle run</a> more times and race back faster after each waggle run. </p>
<h2>Making mistakes</h2>
<p>This dance is difficult to produce. The dancer is not only running – covering about one body length per second – while trying to maintain the correct waggle angle and duration. It is also usually in total darkness, amid a crowd of jostling bees and on an irregular surface. </p>
<p>Bees therefore can make <a href="https://doi.org/10.1016/j.anbehav.2014.05.016">three different types of mistakes</a>: pointing in the wrong direction, signaling the wrong distance, or making more errors in performing the figure eight dance pattern – what researchers call disorder errors. The first two mistakes make it harder for recruits to find the location being communicated. Disorder error may make it harder for recruits to follow the dancer.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/8EAZvnjfnac?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">This video, from the Nieh lab, shows the bees’ “waggle run.”</span></figcaption>
</figure>
<p>Scientists knew that all bees of the species <em>Apis mellifera</em> begin to forage and dance only as <a href="https://www.youtube.com/watch?v=9ePic3dtykk&ab_channel=NationalGeographic">they get older</a> and that they also <a href="https://www.biorxiv.org/content/10.1101/179408v1.abstract">follow experienced dancers</a> before they first attempt to dance. Could they be learning from practiced teachers?</p>
<h2>A ‘forbidden’ bee experiment</h2>
<p>My colleagues and I thus created isolated <a href="https://www.science.org/doi/10.1126/science.ade1702">experimental colonies of bees</a> that could not observe other waggle dances before they themselves danced. Like the ancient experiment described by Herodotus, these bees could not observe the dance language because they were all the same age and had no older, experienced bees to follow. In contrast, our control colonies contained bees of all ages, so younger bees could follow the older, experienced dancers.</p>
<p>We recorded the first dances of bees living in colonies with both population age profiles. The bees that could not follow the dances of experienced bees produced dances with significantly more directional, distance and disorder errors than the dances of control novice bees.</p>
<p>We then tested the same bees later, when they were experienced foragers. Bees who had lacked teachers now produced significantly fewer directional and disorder errors, possibly because they had more practice or had learned by eventually following other dancers. The dances of the older control bees from colonies with teachers remained just as good as their first dances.</p>
<p>This finding told us that bees are therefore born with some knowledge of how to dance, but they can learn how to dance even better by following experienced bees. This is the first known example of such complex social learning of communication in insects and is a form of animal culture.</p>
<h2>Dance dialects are about distance</h2>
<p>A mystery remained with respect to the bees that had lacked dance teachers early on. They could never correct their distance errors. They continued to overshoot, communicating greater distances than normal. So, why is this interesting to scientists? The answer may lie in how distance communication could adapt to local conditions.</p>
<p>There can be significant differences in where food is distributed in different environments. As a result, different honeybee species have evolved different “<a href="https://doi.org/10.1098/rspb.2020.0190">dance dialects</a>,” described as the relationship between the distance to a food source and the corresponding waggle dance duration.</p>
<p>Interestingly, these dialects vary, even within the <a href="https://doi.org/10.1242/jeb.242404">same honeybee species</a>. Researchers suspect this variation exists because colonies, even of the same species, can live in very different environments.</p>
<p>If learning language is a way to cope with different environments, then perhaps each colony should have a distance dialect tailored to its locale and passed on from experienced bees to novices. If so, our teacher-deprived individual bees may never have corrected their distance errors because they acquired, on their own, a different distance dialect. </p>
<p>Normally, this dialect would be learned from experienced bees, but could potentially change within a single generation if their environmental conditions changed or if the colony swarmed to a new location. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/513853/original/file-20230307-22-ocsgvb.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Many bees packed together on a slanted honeycomb" src="https://images.theconversation.com/files/513853/original/file-20230307-22-ocsgvb.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/513853/original/file-20230307-22-ocsgvb.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/513853/original/file-20230307-22-ocsgvb.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/513853/original/file-20230307-22-ocsgvb.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/513853/original/file-20230307-22-ocsgvb.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/513853/original/file-20230307-22-ocsgvb.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/513853/original/file-20230307-22-ocsgvb.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The complex terrain bees must navigate while doing their dances.</span>
<span class="attribution"><a class="source" href="https://drive.google.com/file/d/1huzu5VSlr7NycnXUdvg_7zzOaTaW9YHS/view">Dong Shihao</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>In addition, each colony has a “dance floor,” or the space where bees dance, with <a href="https://drive.google.com/file/d/1huzu5VSlr7NycnXUdvg_7zzOaTaW9YHS/view?usp=share_link">complex terrain</a> that the dancers may learn to better navigate over time or by following in the footsteps of older dancers. </p>
<p>These ideas remain to be tested but provide a foundation for future experiments that will explore cultural transmission between older and younger bees. We believe that this study and future studies will expand our understanding of collective knowledge and language learning in animal societies.</p><img src="https://counter.theconversation.com/content/200896/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>James C. Nieh does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Honeybees possess one of the most complex examples of nonhuman communication. New research suggests that it is learned and culturally passed down from older to younger bees.James C. Nieh, Associate Dean and Professor of Biology, University of California, San DiegoLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1928102023-01-31T13:15:48Z2023-01-31T13:15:48ZMini creatures with mighty voices know their audience and focus on a single frequency<figure><img src="https://images.theconversation.com/files/506448/original/file-20230125-20-qo2fa8.jpg?ixlib=rb-1.1.0&rect=799%2C1210%2C3639%2C1815&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The coquí frog, *Eleutherodactylus coqui*, is loud enough to wake people at night.</span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/atardecerboricua/6412552985/in/photolist-nqd2wM-siBCx-9U7tfN-3dc6jS-nqYftj-2obkoYQ-nsGGeX-2ob6cY8-3dc5gN-2obhqNm-2ob784C-4wSjbL-MJzjq-8FRYs3-8FNNcF-8FNMP8-8FNLHa-K2daUb-aLE1An-D9pPx5-bvssQd-dK5Cia-dKb61y-dKb6nj-CD8QSt-K2daXs">Éktor/flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span></figcaption></figure><p>In the cloud forests of South America, amid the constant cacophony of bird and insect noise, a deafening blare pierces through the background from time to time. Belonging to the loudest known bird, the white bellbird, <em>Procnias albus</em>, this sound would be painful to humans listening nearby and capable of causing <a href="https://www.cdc.gov/nceh/hearing_loss/what_noises_cause_hearing_loss.html">immediate hearing damage from about a yard away</a>.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/dvK-DujvpSY?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Listen to the world’s loudest bird call.</span></figcaption>
</figure>
<p><a href="https://doi.org/10.1016/j.cub.2019.09.028">Made exclusively by males serenading females</a>, these vocalizations can reach peak levels of more than 120 decibels on the sound pressure level scale (dB SPL), which is equivalent to a <a href="https://planenerd.com/decibels-of-a-jet-engine/">jet aircraft taking off from 100 yards away</a>. <a href="https://doi.org/10.1016/j.cub.2019.09.028">The female bellbird listens some distance from the male</a>, presumably trading off being close enough to assess his quality as a mate without damaging her ears. </p>
<p>I study the <a href="https://scholar.google.com/citations?hl=en&user=IekcMzwAAAAJ">hearing ability of animals and the sounds they make</a> to communicate. A great number of calls exist throughout the animal kingdom – and many are used to attract mates or defend territories. Evolution has favored those able to make sounds efficiently. The <a href="https://doi.org/10.1006/anbe.2003.2093">louder and more focused</a> the energy in the call and the <a href="https://doi.org/10.1007/978-1-4612-1182-2_7">closer in pitch</a> it is to the intended listener’s optimal hearing range, the farther away a potential mate or rival will hear it. </p>
<p>Many large mammals, such as singing whales, roaring lions and rumbling elephants, <a href="https://doi.org/10.1007/BF00299740">produce loud low-pitched sounds</a> that travel especially well through most habitats. Because of their petite physical size, small animals are not capable of making these far-reaching low-frequency sounds. </p>
<p>As a workaround, a number of small creatures have found ingenious ways to deliver their messages loudly, despite their size.</p>
<h2>Ultrasonic calls</h2>
<p>Human ears are most sensitive to the <a href="https://www.researchgate.net/figure/Audiogram-showing-the-average-human-threshold-for-pure-tones-obtained-in-a-sound-field_fig2_6597029">highest notes on a piano</a> – about 4 kHz – a unit of measurement that is the physical metric for pitch. Anything above 20 kHz is considered ultrasonic – undetectable to human ears. But such sounds are not undetectable to all ears.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/506443/original/file-20230125-7959-o0r30p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Close-up photo of a bat's head showing large and elaborately ridged ears." src="https://images.theconversation.com/files/506443/original/file-20230125-7959-o0r30p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/506443/original/file-20230125-7959-o0r30p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=398&fit=crop&dpr=1 600w, https://images.theconversation.com/files/506443/original/file-20230125-7959-o0r30p.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=398&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/506443/original/file-20230125-7959-o0r30p.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=398&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/506443/original/file-20230125-7959-o0r30p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/506443/original/file-20230125-7959-o0r30p.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/506443/original/file-20230125-7959-o0r30p.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=501&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The greater bulldog bat’s ear is engineered for ultrasonic hearing.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/thomascuypers/49186734333/in/photolist-e5mhwn-2hWsStF-2hWvqig-XMHZf9-XMHZaE-XMHZ8q-qPdXtS">Thomas Cuypers/flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span>
</figcaption>
</figure>
<p>For example, the greater bulldog bat, <em>Noctilio leporinus</em>, can produce <a href="https://doi.org/10.1007/BF00184422">ultrasonic echolocation calls between 30 and 60 kHz</a> when hunting prey and maneuvering during flight. These calls can also get <a href="https://doi.org/10.1371/journal.pone.0002036">incredibly loud – above 140 dB SPL</a>.</p>
<p>Many other small mammals, including other bats, and even some primates such as tiny tarsiers, produce <a href="https://doi.org/10.1098/rsbl.2011.1149">loud ultrasonic sounds humans can’t perceive</a>. In part, these sounds can reach such volumes because their acoustic power is concentrated in a pure tone or single frequency. </p>
<h2>Creating speakers</h2>
<p>Insects are some of the smallest animals to produce loud sounds, chief among them the cicadas and the orthopterans, which include katydids, grasshoppers and crickets. </p>
<p>In North America, the robust conehead, <em>Neoconocephalus robustus</em>, a type of katydid, <a href="https://doi.org/10.1016/0022-1910(77)90127-5">regularly surpasses 105 dB SPL</a>. These calls are produced to attract mates and, like many such calls, are competing against a clamor of comparable sounds from similar species. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/506436/original/file-20230125-16-uec92.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Close-up photo of an insect on a leaf with a hole chewed into it roughly the size of the insect's wings." src="https://images.theconversation.com/files/506436/original/file-20230125-16-uec92.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/506436/original/file-20230125-16-uec92.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=391&fit=crop&dpr=1 600w, https://images.theconversation.com/files/506436/original/file-20230125-16-uec92.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=391&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/506436/original/file-20230125-16-uec92.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=391&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/506436/original/file-20230125-16-uec92.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=491&fit=crop&dpr=1 754w, https://images.theconversation.com/files/506436/original/file-20230125-16-uec92.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=491&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/506436/original/file-20230125-16-uec92.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=491&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A two-spotted tree cricket, <em>Neoxabea bipunctata</em>, chews a hole just the right size for its fore wings. It then ‘sings’ by poking the wings through the hole and rubbing them together.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/pcoin/4027378063">Patrick Coin/flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-sa/4.0/">CC BY-NC-SA</a></span>
</figcaption>
</figure>
<p>Some insects go one step further, amplifying their sounds by building the functional equivalent of audio speakers. Some tree crickets chew holes in leaves, place their vibrating wings in the opening and <a href="https://doi.org/10.1038/255142a0">use the surrounding leaf as a baffle</a> to prevent the loss of sound energy around the edges of their wings. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/506457/original/file-20230125-24-w5uxcx.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Drawing depicting twin burrows joining below ground in a chamber inhabited by a cricket." src="https://images.theconversation.com/files/506457/original/file-20230125-24-w5uxcx.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/506457/original/file-20230125-24-w5uxcx.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=510&fit=crop&dpr=1 600w, https://images.theconversation.com/files/506457/original/file-20230125-24-w5uxcx.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=510&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/506457/original/file-20230125-24-w5uxcx.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=510&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/506457/original/file-20230125-24-w5uxcx.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=641&fit=crop&dpr=1 754w, https://images.theconversation.com/files/506457/original/file-20230125-24-w5uxcx.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=641&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/506457/original/file-20230125-24-w5uxcx.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=641&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The male mole cricket sings from his specially designed burrow, which amplifies sound like a horn.</span>
<span class="attribution"><a class="source" href="https://en.wikipedia.org/wiki/Mole_cricket#/media/File:Mole_cricket_burrow.png">Ian Alexander, new drawing based on Bennet-Clark, 1970 with public domain insect from Lydekker 1879</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>Mole crickets, <em>Gryllotalpa vineae</em>, go even further by <a href="https://doi.org/10.1080/09524622.1996.9753321">constructing a burrow that acts like a wind instrument</a>, creating a cavity of vibrating air that amplifies the sound energy they produce. <a href="https://doi.org/10.1242/jeb.128.1.383">These crickets’ songs can travel almost half a mile</a> (0.8 kilometer).</p>
<h2>Irksome invaders</h2>
<p>The <a href="https://welcome.topuertorico.org/coqui.shtml">official mascot of Puerto Rico</a> is a 1-to-2-inch (2-5-centimeter) frog called the coquí, <em>Eleutherodactylus coqui</em>, whose call is a combination of two pure tones – “ko” and “kee,” from which it gets its name. At 114-120 dB SPL, the frog’s calls are so loud they actually must <a href="https://doi.org/10.1121/1.402844">protect their own hearing when vocalizing</a>, by increasing the air pressure inside their middle ear.</p>
<p>Unfortunately, in the past few decades humans have accidentally <a href="https://www.pbs.org/newshour/science/grab-earplugs-invasive-coqui-frogs-gain-foothold-california">introduced the coquí</a> to a number of areas outside their native range, in particular the Hawaiian islands, <a href="https://www.oahuisc.org/coqui-frog/">where they have no natural predators</a> and <a href="https://www.biisc.org/pest/coqui/">have become invasive pests</a>. Since coquí calls are within an octave of humans’ best hearing – and they’re nocturnal – many Hawaiians suffer <a href="https://www.nps.gov/articles/coqui.htm">sleep disruptions because of the tiny frogs</a>.</p>
<p>So even if you’re small, it’s not impossible to make yourself heard. You just have to blast all your acoustic energy in a single frequency, and hit the sweet spot of your audience’s hearing.</p><img src="https://counter.theconversation.com/content/192810/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Bernard Lohr has received funding from the National Institute on Deafness and Other Communication Disorders and the U. S. Fish and Wildlife Service. </span></em></p>From insects to birds to bats to frogs, these little loudmouths have found ingenious ways to deliver their messages at high volume.Bernard Lohr, Associate Professor of Biological Sciences, University of Maryland, Baltimore CountyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1758962022-04-11T15:17:56Z2022-04-11T15:17:56ZAllow me to introduce myself: Squirrels use rattle calls to identify themselves<figure><img src="https://images.theconversation.com/files/457413/original/file-20220411-16-h30zck.jpg?ixlib=rb-1.1.0&rect=21%2C0%2C4655%2C3120&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Squirrel rattle calls may be a form of announcing their presence.</span> <span class="attribution"><span class="source">(Shutterstock)</span></span></figcaption></figure><p>As a scientist who studies squirrel behaviour, one of the most common questions I am asked is: “How do I get them out of my yard?”</p>
<p>It’s not as easy being a squirrel as you might think. They live a <a href="https://doi.org/10.1139/z95-133">relatively solitary life</a> guarding hard-won food stores to survive the tough winters here in Canada. The behaviour that my students and I are most interested in is how these squirrels use sounds, or what we refer to as vocal communication, to help them make it through this tough life.</p>
<h2>Solitary creatures</h2>
<p>The North American red squirrel lives a somewhat solitary life. They spend most of their days in a 50-100 metre territory foraging for pine cones and other food sources like berries and mushrooms. </p>
<p>Individuals spend time gathering cones throughout the summer and fall months, storing them in a central location called a midden. They can be rather protective of these middens, as squirrels are known to <a href="https://doi.org/10.1644/1545-1542(2005)086%3C0108:FPILRS%3E2.0.CO;2">steal a great deal from each other</a>. In fact, a squirrel can steal up to 90 per cent of its stores from neighbouring squirrels. </p>
<p>These little thieves run back and forth moving and stealing cones to survive the tough Canadian winters. While they are stealing and storing, <a href="https://www.jstor.org/stable/4534898">squirrels often produce a loud call</a>, termed a rattle. I am keenly interested in this call — my students and I watch and record squirrels to understand what these rattles might be communicating. </p>
<p>Historically it was assumed that this rattle call was produced to make sure that squirrels knew to stay out of each other’s territories — in a sense, a warning that if you enter you may encounter some aggression from the squirrel that lives there. My research has been exploring <a href="https://shannonmdigweed.weebly.com/squirrel-speak-and-pika-puns">a slightly different view of this call</a>.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/IMOQv1QHxSQ?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Recordings of various red squirrel vocal communications.</span></figcaption>
</figure>
<h2>Neighbours and strangers</h2>
<p>It is possible that the call still warns other squirrels to stay out, but its <a href="https://doi.org/10.1093/czoolo/58.5.758">primary function is to identify the caller to all those who are listening</a>. As a squirrel moves through its own territory, and the territories of its neighbours, they produce intermittent rattle calls. These calls are <a href="https://www.jstor.org/stable/20799540">an announcement of who and where that squirrel is</a>. Listeners then know where their various neighbours are throughout the day. This knowledge can help mitigate costly aggressive interactions, chases and fights. </p>
<p>In addition, by communicating who is calling, the rattle can signal to listeners who is more likely to steal from you and <a href="https://doi.org/10.1016/j.anbehav.2017.08.024">thus a more threatening neighbour</a>. Some neighbours may be more likely to steal from you than others. </p>
<p>In behavioural ecology, this is referred to as <a href="https://doi.org/10.1006/anbe.1994.1047">the “dear enemy” effect</a>, and supposes that in maintaining a territory it is useful to know the relative threat posed by your neighbours versus the threat posed by strangers. In most cases, a known neighbour is far less of a threat than a stranger. </p>
<p>With red squirrels, it has been shown that <a href="https://doi.org/10.1016/j.anbehav.2017.08.024">different neighbours do have different levels of threat</a>. As a result, knowing who your neighbour is by their rattle call reveals the relative threat they represent and therefore the necessary response.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/457043/original/file-20220408-11-ggugy7.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C4684%2C3113&q=45&auto=format&w=1000&fit=clip"><img alt="a young red squirrel carries a pine cone" src="https://images.theconversation.com/files/457043/original/file-20220408-11-ggugy7.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C4684%2C3113&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/457043/original/file-20220408-11-ggugy7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/457043/original/file-20220408-11-ggugy7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/457043/original/file-20220408-11-ggugy7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/457043/original/file-20220408-11-ggugy7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/457043/original/file-20220408-11-ggugy7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/457043/original/file-20220408-11-ggugy7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Squirrels lead solitary lives.</span>
<span class="attribution"><span class="source">(Shutterstock)</span></span>
</figcaption>
</figure>
<h2>Social calls</h2>
<p>Self-announcement or self-identification is a common vocal behaviour across many different species. Several marine mammal species, <a href="https://doi.org/10.1073/pnas.0509918103">such as dolphins</a> <a href="https://doi.org/10.1016/j.beproc.2008.04.007">and seals</a>, also produce calls that contain information about who is calling. They are used to identify social companions and offspring. </p>
<p>Several species of primates also have calls that contain information about who is calling. Again, these are often used in social interactions to help mitigate aggression during foraging — <a href="https://doi.org/10.1006/anbe.1998.1031">baboons</a> and <a href="https://doi.org/10.1002/ajp.20398">capuchin monkeys</a>, for example. So it’s not unusual that a species like the red squirrel would also have information about who is calling to help them with difficult territory interactions. </p>
<p>My students and I have found that squirrels produce these calls throughout their territory as well as in the territory of close neighbours. By conducting experiments on when and where the squirrels produce the rattle call, we hope to show that the occurrence of this call is about announcing who and where you are, and not strictly about getting others out of your territory.</p><img src="https://counter.theconversation.com/content/175896/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Shannon M. Digweed does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>North American red squirrels produce a range of sounds, but their distinctive rattle call may have more to do with identifying themselves than warning off other squirrels.Shannon M. Digweed, Associate professor, Psychology and Biological Sciences, MacEwan UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1760202022-02-14T13:20:05Z2022-02-14T13:20:05ZPhysics and psychology of cats – an (improbable) conversation<figure><img src="https://images.theconversation.com/files/443350/original/file-20220131-15-1ndq1m6.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C3354%2C2464&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">According to researcher Marc-Antoine Fardin, under the right circumstances, cats’ bodies can behave like liquids.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/kitty-royalty-free-image/127379452?adppopup=true">Nevena Uzurov/Moment via Getty Images</a></span></figcaption></figure><p>Have you wondered why cats are so nimble and seem to fit perfectly in cups, boxes and other small places? Or how cats communicate with humans? </p>
<p>Marc Abrahams, editor of the <a href="https://improbable.com/">Annals of Improbable Research</a> and master of ceremonies of the annual Ig Nobel Prize, <a href="https://www.bu.edu/psych/profile/jean-gleason-phd/">Jean Berko Gleason</a>, psycholinguist and professor emerita of Psychological and Brain Science at Boston University, and <a href="https://scholar.google.com/citations?user=uxmLb3IAAAAJ&hl=en">Marc-Antoine Fardin</a>, rheology researcher at the University of Paris, discussed this and other cat science questions, probable and improbable, in a fascinating and humorous webinar co-hosted by The Conversation and the Annals of Improbable Research.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/2JbYU-IccwM?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Physics and psychology of cats - an (improbable) conversation.</span></figcaption>
</figure>
<p>Fardin is the winner of the Ig Nobel Prize in physics in 2017 for exploring the use of fluid dynamics to probe the question “<a href="https://theconversation.com/answering-the-question-that-won-me-the-ig-nobel-prize-are-cats-liquid-86589">Can a cat be both solid and a liquid</a>?”</p>
<p><em>Below are some highlights from the discussion. Please note that answers have been edited for brevity and clarity.</em></p>
<hr>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/443367/original/file-20220131-27-24c657.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Beige and white cat sleeping snugly in tight blue box." src="https://images.theconversation.com/files/443367/original/file-20220131-27-24c657.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/443367/original/file-20220131-27-24c657.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=416&fit=crop&dpr=1 600w, https://images.theconversation.com/files/443367/original/file-20220131-27-24c657.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=416&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/443367/original/file-20220131-27-24c657.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=416&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/443367/original/file-20220131-27-24c657.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=522&fit=crop&dpr=1 754w, https://images.theconversation.com/files/443367/original/file-20220131-27-24c657.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=522&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/443367/original/file-20220131-27-24c657.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=522&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">As many cat owners know, cats tend to like squeezing themselves into small spaces.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/perfect-fit-royalty-free-image/169242612?adppopup=true">Benjamin Torode/Moment via Getty Images</a></span>
</figcaption>
</figure>
<p><strong>Marc Abrahams: Rheology is studying anything, everything that flows, and, thanks to you, largely, that now includes cats. How did that happen?</strong></p>
<p><strong>Marc-Antoine Fardin:</strong> I was on the internet a few years ago, and I saw this set of webpages that were discussing whether cats are liquid. And then they had the definition of a liquid. And usually the definition of a liquid is material that takes the shape of its container. [For example,] if I pour liquid into a mug, the liquid is going to take the shape of the mug, and if I pour it into a wine glass it is going to take the shape of the glass.</p>
<p>If you look at a bunch of different cats, there are many different pictures and experiments that have been run by many people around the world where you see the cats taking the shape of the container [they are in], like a box or a sink. People were asking this question. And so I took this question and put it into the modern lingo of rheology. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/443369/original/file-20220131-21-riq2l1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Cat in a bathroom sink" src="https://images.theconversation.com/files/443369/original/file-20220131-21-riq2l1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/443369/original/file-20220131-21-riq2l1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/443369/original/file-20220131-21-riq2l1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/443369/original/file-20220131-21-riq2l1.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/443369/original/file-20220131-21-riq2l1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/443369/original/file-20220131-21-riq2l1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/443369/original/file-20220131-21-riq2l1.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Are cats a liquid if they take the shape of the container they are in?</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/cat-sitting-in-sink-royalty-free-image/674510046">Marion Nivard/FOAP via Getty Images</a></span>
</figcaption>
</figure>
<p><strong>Marc Abrahams: What does the compressibility of cats refer to?</strong></p>
<p><strong>Marc-Antoine Fardin:</strong> Gas in comparison to liquid is compressible. So it means that if you were to push it, you could change its volume. And so for cats, once you answer that the cat might be a liquid, you might also push the question a little further and ask if in some cases a cat could be a gas. And so if it is a gas, it should be compressible. And that’s an experiment that I have not done because I don’t want to get into any trouble.</p>
<p><strong>Beth Daley (to Jean Berko Gleason): Based on your expertise as a psycholinguist, have humans been communicating efficiently with cats? And if not, how should they?</strong></p>
<p><strong>Jean Berko Gleason:</strong> Cats have been communicating very efficiently with us. We’ve had cats as pets for, like, 14,000 years. And in 14,000 years, the cats have told us that they want to live with us, and that they would like a comfortable bed, and they want food, and they want us to snuggle with them. In other words, the cats have really communicated all of their interests and needs such that we’re running around doing whatever they have in mind. So they’re doing a very good job. </p>
<p>Our problem with communicating with cats is that you can try to train cats, but [they are very stubborn]. For instance, cats who take part in psychology studies frequently … just leave. The cats do not hang around for the rest of your study. </p>
<p>What people are trying to do really is learn much more about their body language. One of the things that has happened in recent years is that we [have] begun to understand that cats have different facial expressions. And there [are] some bits of research recently in which veterinarians, or people who work in cat hospitals, they’re able to tell the five or six cat facial expressions apart, but we’re not terribly good at that.</p>
<p><em><a href="https://youtu.be/2JbYU-IccwM">Watch the full webinar</a> to hear about additional science behind Fardin’s study on the physics of cats, Berko Gleason’s famous research on children’s language-learning abilities and more.</em></p><img src="https://counter.theconversation.com/content/176020/count.gif" alt="The Conversation" width="1" height="1" />
Have you wondered why cats are so nimble and seem to fit perfectly in cups, boxes, and other small places? Or how cats communicate with humans? A physicist and a psychologist explain.Beth Daley, Executive Editor and General ManagerThalia Plata, EditorLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1539392021-02-09T13:31:19Z2021-02-09T13:31:19ZScientists at work: New recordings of ultrasonic seal calls hint at sonar-like abilities<figure><img src="https://images.theconversation.com/files/382875/original/file-20210207-18-1wwb8n2.jpg?ixlib=rb-1.1.0&rect=75%2C42%2C2766%2C1697&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Scientist and seal, under the Antarctic ice.</span> <span class="attribution"><span class="source">McMurdo Oceanographic Observatory</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span></figcaption></figure><figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/382838/original/file-20210206-17-q3qr1u.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="SCUBA divers sit around a square hole cut in Antarctic ice" src="https://images.theconversation.com/files/382838/original/file-20210206-17-q3qr1u.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/382838/original/file-20210206-17-q3qr1u.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=800&fit=crop&dpr=1 600w, https://images.theconversation.com/files/382838/original/file-20210206-17-q3qr1u.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=800&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/382838/original/file-20210206-17-q3qr1u.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=800&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/382838/original/file-20210206-17-q3qr1u.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1005&fit=crop&dpr=1 754w, https://images.theconversation.com/files/382838/original/file-20210206-17-q3qr1u.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1005&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/382838/original/file-20210206-17-q3qr1u.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1005&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Divers inside the shelter hut prepare to drop into the ocean.</span>
<span class="attribution"><span class="source">McMurdo Oceanographic Observatory</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>I’m sitting on the edge of a hole drilled through 15 feet of Antarctic sea ice, about to descend into the frigid ocean of the southernmost dive site in the world. I wear nearly 100 pounds of gear – a drysuit and gloves, multiple layers of insulation, scuba tank and regulators, lights, equipment, fins and over 40 pounds of lead to counteract all that added buoyancy.</p>
<p>I do a final check with my dive buddies: Air? Hoses? Weights? Then, one by one, we put in our mouthpieces, plop into the hole and sink out of sight into the dark.</p>
<p>As we frog-kick along, following our lights toward the work site, <a href="http://weddellsealscience.com/">a Weddell seal glides by</a> with a few effortless undulations. It glances sideways at us a couple of times, as if doing a double-take.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/382841/original/file-20210206-17-2c0iz3.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Weddell seal swims by SCUBA diver with scientific equipment" src="https://images.theconversation.com/files/382841/original/file-20210206-17-2c0iz3.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/382841/original/file-20210206-17-2c0iz3.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/382841/original/file-20210206-17-2c0iz3.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/382841/original/file-20210206-17-2c0iz3.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/382841/original/file-20210206-17-2c0iz3.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/382841/original/file-20210206-17-2c0iz3.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/382841/original/file-20210206-17-2c0iz3.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A Weddell seal swims by as Paul Cziko works.</span>
<span class="attribution"><span class="source">McMurdo Oceanographic Observatory</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>In contrast to us awkward, gear-laden human divers, Weddell seals are completely at home under the ice. They can hold their breath for over 80 minutes and dive to a depth of nearly 2,000 feet. Somehow they explore, find food and return to their isolated breathing holes even when it’s completely dark.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/382840/original/file-20210206-21-181rvme.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Exit hole for divers cut through 15 feet of ice" src="https://images.theconversation.com/files/382840/original/file-20210206-21-181rvme.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/382840/original/file-20210206-21-181rvme.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/382840/original/file-20210206-21-181rvme.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/382840/original/file-20210206-21-181rvme.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/382840/original/file-20210206-21-181rvme.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/382840/original/file-20210206-21-181rvme.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/382840/original/file-20210206-21-181rvme.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">There’s just one way out for the research divers.</span>
<span class="attribution"><span class="source">McMurdo Oceanographic Observatory</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>We, on the other hand, have about 30 minutes of bottom time before our hands get too cold to work. Then we make our way back to the dive line. Its flags and blinking lights guide us to our one and only way out.</p>
<p>During my deployment to Antarctica in 2018, I participated in 40 such dives to help maintain the <a href="https://moo-antarctica.net/">McMurdo Oceanographic Observatory</a>. Polar marine biologist <a href="https://scholar.google.com/citations?user=Zn3asugAAAAJ&hl=en&oi=ao">Paul Cziko</a> installed the 70-foot-deep, seafloor-mounted recorder in 2017. Known affectionately as “MOO,” it resembled R2-D2 in both looks and charm. For two years, MOO successfully sent continuous audio, video and ocean data back to our onshore lab via cable connection. It also streamed a real-time view of this enthralling Antarctic marine ecosystem: ice glittering on the seafloor and ceiling, <a href="https://www.sciencemag.org/news/2020/09/creepy-sea-spiders-have-evolved-be-tough">giant sea spiders</a> and isopods creeping among the sponges and soft corals.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/382839/original/file-20210206-20-1htjv2x.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="SCUBA diver accesses underwater recording equitpment" src="https://images.theconversation.com/files/382839/original/file-20210206-20-1htjv2x.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/382839/original/file-20210206-20-1htjv2x.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/382839/original/file-20210206-20-1htjv2x.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/382839/original/file-20210206-20-1htjv2x.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/382839/original/file-20210206-20-1htjv2x.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/382839/original/file-20210206-20-1htjv2x.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/382839/original/file-20210206-20-1htjv2x.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The McMurdo Oceanographic Observatory, mounted to the seafloor, 70 feet below the Antarctic ice.</span>
<span class="attribution"><span class="source">McMurdo Oceanographic Observatory</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Seals were only occasionally caught on camera, but their haunting calls dominated the soundscape. Although the initial goal of the MOO was to support research on the <a href="https://www.openaccessgovernment.org/antarctic-notothenioid-fishes/41433/">ice-adapted fishes native to the area</a>, analysis of the audio recordings led us to a surprising discovery. <a href="https://doi.org/10.1121/10.0002867">Weddell seals produce ultrasonic calls</a> – sequences of chirps and whistles with frequencies well above 20 kHz, the upper limit of human hearing. </p>
<h2>Surprising seal sounds</h2>
<p>These newly discovered call types – nine in total, with base frequencies above 20 kHz and ranging up to nearly 50 kHz – are the first report of such high-frequency vocalizations in any wild seals, sea lions and walruses, the group of sea mammals collectively known as pinnipeds.</p>
<p>Although scientists have studied Weddell seals for many decades and <a href="https://www.researchgate.net/publication/258836261_Quantitative_analysis_of_the_underwater_repertoire_of_the_Weddell_seal_Leptonychotes_weddellii">described much of their diverse vocal repertoire</a>, acoustic recording has historically been limited by time and equipment constraints. Most prior studies sampled within the human-audible range only for short stints during the Antarctic field season.</p>
<p>The MOO was the first long-term observatory of its kind, and its cutting-edge technology let us collect an unprecedented data set, including sounds with frequencies up to about 10 times higher than most previous studies.</p>
<p>Our discovery begs the question: What do the seals use their high-pitched ultrasonic calls for? One possibility is that they represent a form of active biosonar, similar to the <a href="https://doi.org/10.1007/978-1-4614-9146-0_1">echolocation used by bats and dolphins</a>. That is, the returning echoes of their high-frequency sounds may provide information to the seals about their environment and potential prey.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/NE-sNx1R2L4?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Weddell seal producing ultrasonic vocalizations in McMurdo Sound, Antarctica.</span></figcaption>
</figure>
<p>Previous studies have <a href="https://doi.org/10.1121/1.428506">argued that pinnipeds do not echolocate</a> because they do not possess the specialized anatomy for producing or processing tightly focused sounds with very short time intervals. Additionally, their known calls don’t exhibit the telltale characteristics of echolocation pulses, such as accelerating in time as an animal approaches a target.</p>
<p>But the ability to use sound to “see” their surroundings would be especially useful during very low-visibility conditions – like what the seals encounter under thick ice or in the polar winter, when there is no daylight for four months. Our preliminary findings indeed suggested that the use of certain high-frequency pulsed vocalizations increased during the dark Antarctic winter. It is also very likely, and not mutually exclusive, that the seals use ultrasonic calls for communication, as <a href="https://doi.org/10.1139/z83-194">has been shown for their human-audible calls</a>.</p>
<h2>Serendipitous discovery raises more questions</h2>
<p>It’s still a mystery how seals navigate and forage under the ice in certain conditions. Weddell seals and other seals that live on the ice <a href="https://doi.org/10.1016/j.dsr2.2012.07.006">have many adaptations</a> for diving and <a href="https://doi.org/10.1139/z92-238">finding their breathing holes again</a>, including good low-light vision, spatial memory and extremely sensitive whiskers, called vibrissae.</p>
<p>However, these senses each have their limitations. Sometimes there may be literally no ambient light where the seals are diving. Following the same routes on every dive would preclude finding new patches of mobile prey. And the tactile sensation provided by whiskers is only useful at close range.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/382836/original/file-20210206-17-1o3tql4.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Weddell seal" src="https://images.theconversation.com/files/382836/original/file-20210206-17-1o3tql4.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/382836/original/file-20210206-17-1o3tql4.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=337&fit=crop&dpr=1 600w, https://images.theconversation.com/files/382836/original/file-20210206-17-1o3tql4.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=337&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/382836/original/file-20210206-17-1o3tql4.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=337&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/382836/original/file-20210206-17-1o3tql4.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/382836/original/file-20210206-17-1o3tql4.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/382836/original/file-20210206-17-1o3tql4.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Weddell seals swim in challenging conditions.</span>
<span class="attribution"><span class="source">McMurdo Oceanographic Observatory</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>It seems obvious that seals would also use sound to gain information about their surroundings. Indeed, Weddell seals and other related species can <a href="https://doi.org/10.1007/s00359-013-0813-y">hear frequencies up to at least 60 kHz</a>, and researchers have found that seals use acoustic cues, when available, <a href="https://doi.org/10.1139/z92-238">to navigate</a>. However, actively emitting high-frequency chirps and interpreting their own echoes would definitely be a step beyond passive listening.</p>
<p>[<em>Deep knowledge, daily.</em> <a href="https://theconversation.com/us/newsletters/the-daily-3?utm_source=TCUS&utm_medium=inline-link&utm_campaign=newsletter-text&utm_content=deepknowledge">Sign up for The Conversation’s newsletter</a>.]</p>
<p>Back in the lab <a href="https://www.usap.gov/videoclipsandmaps/mcmwebcam.cfm">at McMurdo Station</a>, the MOO livestream ran as we worked at our desks. The ethereal trills and chirps of seals filled the air. During their Southern Hemisphere spring breeding season, vocal activity is nearly constant. A couple of monitors showed real-time graphical displays of the incoming data: ocean temperature, salinity, tides. A scrolling audio spectrogram would pull us in every so often, mesmerizing us with colorful squiggles that appeared as we heard the calls – a synchronized visual soundtrack.</p>
<p>Every few minutes, bright wiggles and lines would scroll by in the upper register, announcing sounds that we cannot hear. They are patterned; they are repeated again and again. They are seal voices. If we can decode them, they may tell us <a href="https://doi.org/10.1007/s00227-020-03730-w">more about how these seals thrive</a> in what we humans perceive to be a very challenging environment. As technology sheds new light into the depths, what else will we find?</p><img src="https://counter.theconversation.com/content/153939/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Lisa Munger does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Microphones on the seafloor recorded life under the Antarctic ice for two years – inadvertently catching seal trills and chirps that are above the range of human hearing. Could they be for navigation?Lisa Munger, Instructor of Natural Sciences, University of OregonLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1533452021-02-08T13:36:10Z2021-02-08T13:36:10ZWhen dogs bark, are they using words to communicate?<figure><img src="https://images.theconversation.com/files/380930/original/file-20210127-15-10im32m.jpg?ixlib=rb-1.1.0&rect=0%2C15%2C5023%2C3323&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">'Hey everybody, there's big news happening over here!'</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/close-up-of-dog-with-mouth-open-looking-away-royalty-free-image/1128037858">Wesley Martinez Da Costa/EyeEm via Getty Images</a></span></figcaption></figure><figure class="align-left ">
<img alt="" src="https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=293&fit=crop&dpr=1 600w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=293&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=293&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=368&fit=crop&dpr=1 754w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=368&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=368&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<p><em><a href="https://theconversation.com/us/topics/curious-kids-us-74795">Curious Kids</a> is a series for children of all ages. If you have a question you’d like an expert to answer, send it to <a href="mailto:curiouskidsus@theconversation.com">CuriousKidsUS@theconversation.com</a>.</em></p>
<hr>
<blockquote>
<p><strong>When dogs bark, do they have words? – Sarah W., age 9, Clinton, New York</strong></p>
</blockquote>
<hr>
<p>Does your dog bark a lot? Or is he one of those quiet pooches who barks only when things get really exciting? Most dogs bark at least a little. </p>
<p>Dog barks are not words. But although your dog will never tell you about his parents or the weather or the amazing bone he had yesterday, his barks still communicate important information. </p>
<p>Dog barks are much closer to the noises people make when they accidentally hit their thumb with a hammer – “Ow!” – or open a fantastic present – “Wow!” These sounds convey how someone feels, but not why they feel that way. When other people hear these kinds of sounds, they often come over to see what has happened: How did you hurt yourself? What is this wonderful gift you received?</p>
<p>All dogs, even the tiniest chihuahua, are <a href="https://www.sleddogsocietyofwales.co.uk/evolution-of-dogs.html">descended from great grey wolves</a>. <a href="https://www.akc.org/expert-advice/lifestyle/dog-sounds-meaning/">Wolves almost never bark</a>. <a href="https://www.youtube.com/watch?v=BCPlnvVkZ-I">They howl</a>. Sometimes <a href="https://www.youtube.com/watch?v=lfux0vEcsjM">dogs howl too</a> – but <a href="https://www.thelabradorsite.com/do-wolves-bark/">howling is rarer in dogs</a>. Understanding why wolves howl and dogs bark helps explain what barking is for.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/380934/original/file-20210127-15-1v7to87.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Five wolves howl together in the snow." src="https://images.theconversation.com/files/380934/original/file-20210127-15-1v7to87.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/380934/original/file-20210127-15-1v7to87.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=362&fit=crop&dpr=1 600w, https://images.theconversation.com/files/380934/original/file-20210127-15-1v7to87.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=362&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/380934/original/file-20210127-15-1v7to87.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=362&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/380934/original/file-20210127-15-1v7to87.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=455&fit=crop&dpr=1 754w, https://images.theconversation.com/files/380934/original/file-20210127-15-1v7to87.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=455&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/380934/original/file-20210127-15-1v7to87.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=455&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">United in sound.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/wolves-royalty-free-image/544423903">Fotosearch via Getty Images</a></span>
</figcaption>
</figure>
<p>A howl can be a beautiful sound – almost like a kind of music. And, just as group singing brings people together, so too does <a href="https://animalogic.ca/blog/wolf-pups-practice-pack-behavior-by-howling-together">group howling help a pack of wolves feel united</a>. </p>
<p>Dog barking also brings groups together – but it’s not a beautiful sound. It is a much more urgent noise, just like the sounds you make when you are hurt or very pleased. Many smaller animals, like scrub jays, meerkats and California ground squirrels, make such noisy sounds. They do this <a href="https://www.bl.uk/the-language-of-birds/articles/alarm-and-mobbing-calls#">when they feel frightened by something</a>. In dogs, barking can bring a group together to defend against a danger that can’t be coped with alone. </p>
<p>Wolves don’t need to make sounds like this because they are big and fearsome and don’t often feel threatened. Dogs, on the other hand, are much smaller and weaker than their wolf ancestors – and often need to call the group together.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/380937/original/file-20210127-23-xhcg4p.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A small dog inside a car barks from the driver's side window, which is open." src="https://images.theconversation.com/files/380937/original/file-20210127-23-xhcg4p.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/380937/original/file-20210127-23-xhcg4p.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=358&fit=crop&dpr=1 600w, https://images.theconversation.com/files/380937/original/file-20210127-23-xhcg4p.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=358&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/380937/original/file-20210127-23-xhcg4p.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=358&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/380937/original/file-20210127-23-xhcg4p.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=450&fit=crop&dpr=1 754w, https://images.theconversation.com/files/380937/original/file-20210127-23-xhcg4p.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=450&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/380937/original/file-20210127-23-xhcg4p.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=450&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A call for assistance.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/dog-looking-out-the-car-window-at-parking-area-royalty-free-image/962077654">Seregraff/iStock/Getty Images Plus</a></span>
</figcaption>
</figure>
<p>This is why dogs bark. They are calling their group to get help with something they are not confident they can handle on their own. This doesn’t mean a barking dog is always frightened. He may just be very excited. He badly needs the family to know that there is a stranger coming to the door, or another dog coming close to the house. </p>
<p>Your dog’s barks may not be words, but he probably <a href="https://drsophiayin.com/blog/entry/barking-in-dogs-noise-or-communication/">barks a little differently</a> depending on what kind of thing has got him excited. If you listen closely, you may find you can tell the difference between a bark directed at a package deliverer and one directed toward a friend at the door. The bark to a passing dog may be different than the bark at a passing car. </p>
<p>Your dog doesn’t understand much of what you say, but he listens hard to <a href="https://thebark.com/content/do-dogs-understand-our-words">try to make sense of human language</a>. If you return the compliment and listen hard to his sounds, you may find you can also understand him better, and the two of you will have a richer life together.</p>
<hr>
<p><em>Hello, curious kids! Do you have a question you’d like an expert to answer? Ask an adult to send your question to <a href="mailto:curiouskidsus@theconversation.com">CuriousKidsUS@theconversation.com</a>. Please tell us your name, age and the city where you live.</em></p>
<p><em>And since curiosity has no age limit – adults, let us know what you’re wondering, too. We won’t be able to answer every question, but we will do our best.</em></p><img src="https://counter.theconversation.com/content/153345/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Clive Wynne does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Dogs’ barks say a lot about how they’re feeling.Clive Wynne, Professor of Psychology, Arizona State UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1337362020-05-28T13:46:06Z2020-05-28T13:46:06ZAnimals that can do math understand more language than we think<figure><img src="https://images.theconversation.com/files/337389/original/file-20200525-106815-1o5hdbk.jpg?ixlib=rb-1.1.0&rect=5%2C11%2C3916%2C2599&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">In experiments, African grey parrots have shown an ability with numbers.</span> <span class="attribution"><span class="source">(Shutterstock)</span></span></figcaption></figure><p>It is often thought that humans are different from other animals in some fundamental way <a href="https://today.duke.edu/2019/04/michael-tomasello-what-makes-humans-human">that makes us unique, or even more advanced than other species</a>. These claims of human superiority are sometimes used to <a href="https://animalstudiesrepository.org/cgi/viewcontent.cgi?article=1001&context=moreaexp">justify the ways we treat other animals</a>, in the home, the lab or the factory farm. </p>
<p>So, what is it that makes us so different from other animals? Many philosophers, both <a href="https://www.bartleby.com/34/1/5.html">past</a> and <a href="https://www.hup.harvard.edu/catalog.php?isbn=9780674543300">present</a>, have pointed to our linguistic abilities. These philosophers argue that language not only allows us to communicate with each other, but also makes our mental lives more sophisticated than those that lack language. Some philosophers have gone so far as to argue that creatures that lack a language are not capable of <a href="https://doi.org/10.1111/j.1746-8361.1982.tb01546.x">being rational</a>, making <a href="https://global.oup.com/academic/product/thinking-without-words-9780195341607">inferences</a>, <a href="https://www.hup.harvard.edu/catalog.php?isbn=9780674725836">grasping concepts</a> or even <a href="https://doi.org/10.1080/00048407912341011">having beliefs</a> or <a href="https://cup.columbia.edu/book/the-nature-and-future-of-philosophy/9780231150538">thoughts</a>. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/337387/original/file-20200525-106866-ycp1cb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/337387/original/file-20200525-106866-ycp1cb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/337387/original/file-20200525-106866-ycp1cb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=602&fit=crop&dpr=1 600w, https://images.theconversation.com/files/337387/original/file-20200525-106866-ycp1cb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=602&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/337387/original/file-20200525-106866-ycp1cb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=602&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/337387/original/file-20200525-106866-ycp1cb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=756&fit=crop&dpr=1 754w, https://images.theconversation.com/files/337387/original/file-20200525-106866-ycp1cb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=756&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/337387/original/file-20200525-106866-ycp1cb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=756&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">An illustration of a sulky chimpanzee from Charles Darwin’s 1872 book, ‘The Expression of the Emotions in Man and Animals.’</span>
<span class="attribution"><a class="source" href="https://wellcomecollection.org/works/xaymd6nh">(Wellcome Collection)</a></span>
</figcaption>
</figure>
<p>Even if we are willing to accept these claims, what should we think of animals who are capable of speech? <a href="http://scientificlens.com/why-do-some-birds-mimic-human-speech/">Many types of birds</a>, most famously <a href="https://www.vox.com/videos/2019/3/4/18245163/parrots-humans-speech">parrots</a>, are able to make noises that at least sound linguistic, and <a href="https://www.nationalgeographic.com/news/2018/06/gorillas-koko-sign-language-culture-animals/">gorillas</a> and <a href="https://www.nytimes.com/2007/11/01/science/01chimp.html">chimpanzees</a> have been taught to communicate using sign language. Do these vocalizations or communications indicate that, like humans, these animals are also capable of sophisticated mental processes?</p>
<h2>The philosophy of animal language</h2>
<p>Philosophers have generally answered this question by denying that talking parrots and signing gorillas are demonstrating anything more than clever mimicry. <a href="https://www.pitt.edu/%7Erbrandom/">Robert Brandom</a>, a philosopher at the University of Pittsburgh, has argued that if a parrot says “red” when shown red objects and “blue” when presented with blue ones, <a href="https://www.hup.harvard.edu/catalog.php?isbn=9780674006928">it has not actually demonstrated that it understands the meaning of those words</a>. According to Brandom — and <a href="https://plato.stanford.edu/entries/meaning-holism/">many other philosophers</a> — understanding the meaning of a word requires understanding both the meaning of many other words and the connections that exist between those words.</p>
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Read more:
<a href="https://theconversation.com/can-we-really-know-what-animals-are-thinking-122678">Can we really know what animals are thinking?</a>
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</em>
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<p>Imagine that you bring your toddler niece to a petting zoo for the first time, and ask her if she is able to point to the rabbits. If she successfully does, this might seem like a good indication that she understands what a rabbit is. However, you now ask her to point to the animals. If she points to some rocks on the ground instead of pointing to the rabbits or the goats, does she actually understand what the word “rabbit” means? Understanding “rabbit” involves understanding “animal,” as well as the connection between these two things.</p>
<p>So if a parrot is able to tell us the colour of different objects, that does not necessarily show that the parrot understands the meanings of those words. To do that, a parrot would need to demonstrate that it also understands that red and blue fall underneath the category of colour, or that if something is red all over, it cannot, at the same time, be blue all over.</p>
<p>What sort of behaviour would demonstrate that a parrot or a chimpanzee did understand the words it was using? As a philosopher who focuses on the study of animal cognition, I examine both empirical and theoretical work to answer these types of questions. </p>
<p>In recent research, I argue that <a href="https://doi.org/10.1080/09515089.2019.1688777">testing an animal’s arithmetical capabilities can provide insight into just how much they are capable of understanding</a>. In order to see why, we need to take a brief detour through the philosophy of mathematics.</p>
<h2>Counting animals</h2>
<p>In the late 1800s, the German mathematician and philosopher <a href="https://plato.stanford.edu/entries/frege/">Gottlob Frege</a> tried to demonstrate that arithmetic is an objective science. Many philosophers and mathematicians at the time thought that arithmetic was merely an artifact of human psychology. Frege worried that such an understanding would make arithmetic entirely subjective, placing it on no firmer ground than the <a href="https://global.oup.com/academic/product/gottlob-frege-basic-laws-of-arithmetic-9780199281749?cc=ca&lang=en&">latest fashion trends</a>.</p>
<figure class="align-left zoomable">
<a href="https://images.theconversation.com/files/337137/original/file-20200522-124822-1q2i5m4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/337137/original/file-20200522-124822-1q2i5m4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/337137/original/file-20200522-124822-1q2i5m4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=811&fit=crop&dpr=1 600w, https://images.theconversation.com/files/337137/original/file-20200522-124822-1q2i5m4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=811&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/337137/original/file-20200522-124822-1q2i5m4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=811&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/337137/original/file-20200522-124822-1q2i5m4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1019&fit=crop&dpr=1 754w, https://images.theconversation.com/files/337137/original/file-20200522-124822-1q2i5m4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1019&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/337137/original/file-20200522-124822-1q2i5m4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1019&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The title page of Gottlob Frege’s ‘Die Grundlagen der Arithmetik’ (The Foundations of Arithmetic), published in 1884.</span>
</figcaption>
</figure>
<p>In <a href="https://nupress.northwestern.edu/content/foundations-arithmetic"><em>The Foundations of Arithmetic</em></a>, Frege begins by logically analyzing what sorts of things numbers are. He thinks that the key to this investigation is figuring out what it takes to answer the question “how many?”</p>
<p>If I hand you a deck of cards and ask, “How many?” without specifying what I want counted, it would be difficult to even figure out what sort of answer I am looking for. Am I asking you how many decks of cards, how many cards all together, how many suits or any of the other number of ways of dividing up the deck? If I ask, “How many suits?” and you respond “four,” you are demonstrating not just that you can count, but that you understand what suits are.</p>
<p>Frege thought that the application of number labels depends on being able to grasp the connection between what is being counted and how many of them there are. Replying “four” to the question “How many?” might seem like a disconnected act, like parrots merely calling red objects “red.” However, it is more like your niece pointing to the rabbits while also understanding that rabbits are animals. So, if animals are able to reliably respond correctly to the question “How many?” this demonstrates that they understand the connection between the numerical amount and the objects they are being asked about.</p>
<h2>Animal mathematical literacy</h2>
<p>One example of non-human animals demonstrating a wide range of arithmetical capabilities is the <a href="https://www.audubon.org/news/how-irene-pepperberg-revolutionized-our-understanding-bird-intelligence">work</a> that <a href="https://alexfoundation.org/about/dr-irene-pepperberg/">Irene Pepperberg</a> did with <a href="https://www.nationalgeographic.com/animals/birds/a/african-gray-parrot/">African grey parrots</a>, most famously her subjects Alex and Griffin. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/dKvVaRlz0Y4?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Alex, a grey African parrot, was able to demonstrate an ability with numbers.</span></figcaption>
</figure>
<p>In order to test <a href="https://doi.org/10.1007/s10071-006-0034-7">Alex’s arithmetic capabilities</a>, Pepperberg would show him a set of objects on a tray, and would ask, “How many?” for each of the objects. For example, she would show him a tray with differently shaped objects on it and ask, “How many four-corner?” (Alex’s word for squares.) Alex was able to reliably provide the answer for amounts up to six. </p>
<p>Alex was also able to provide the name for the object if asked to look for a number of those objects. For example, if a tray had different quantities of coloured objects on it including five red objects, and Alex was asked, “What colour is five?” Alex was able to correctly respond by saying “red.” </p>
<p>Pepperberg’s investigations into <a href="https://www.hup.harvard.edu/catalog.php?isbn=9780674008069">the ability to learn and understand basic arithmetic</a> provide examples that show that Alex was able to do more than simply mimic human sounds. Providing the right word when asked, “How many?” required him to understand the connections between the numerical amount and the objects being asked about.</p>
<h2>Animal mathematical skills</h2>
<p>While Pepperberg’s results are impressive, they are far from unique. Numerical abilities have been identified in <a href="http://doi.org/10.1093/oxfordhb/9780199642342.013.002">many different species</a>, most prominently <a href="http://doi.org/10.1093/oxfordhb/9780199642342.013.025">chimpanzees</a>. Some of these capabilities demonstrate that the animals understand the underlying connections between different words and labels. They are therefore doing something more than just mimicking the sounds and actions of the humans around them. </p>
<p>Animals that can do basic arithmetic show us that some really are capable of understanding the terms they use and the connections between them. However, it is still an open question whether their understanding of these connections is a result of learning linguistic expressions, or if their linguistic expressions simply help demonstrate underlying capabilities. </p>
<p>Either way, claims that humans are uniquely able to understand the meanings of words are a bit worse for wear.</p><img src="https://counter.theconversation.com/content/133736/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Erik Nelson receives funding from the Social Sciences and Humanities Research Council. </span></em></p>Some animals demonstrate an ability for mathematics that reflects a more sophisticated understanding of language.Erik Nelson, Phd Student, Philosophy, Dalhousie UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1286862020-02-02T13:39:20Z2020-02-02T13:39:20ZAre you a cat whisperer? How to read Fluffy’s facial expressions<figure><img src="https://images.theconversation.com/files/312307/original/file-20200128-81416-1bjupq6.jpg?ixlib=rb-1.1.0&rect=11%2C0%2C2485%2C1654&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Cats are capable of a expressing a wide range of emotions through facial expressions and body language.</span> <span class="attribution"><span class="source">(Shutterstock)</span></span></figcaption></figure><p>Cats are popular pets: there are an <a href="https://doi.org/10.1007/978-1-4020-3227-1_3">estimated 200 million pet cats worldwide</a>, with more <a href="http://www.fediaf.org/images/FEDIAF_Facts__and_Figures_2018_ONLINE_final.pdf">pet cats than pet dogs</a>. Cats live in about <a href="https://www.canadianveterinarians.net/documents/canada-s-pet-wellness-report2011">38 per cent of Canadian households</a>, <a href="https://www.avma.org/resources-tools/reports-statistics/us-pet-ownership-statistics">25.4 per cent of American households</a> and <a href="https://www.statista.com/statistics/515287/households-owning-a-cat-europe/">25 per cent of European households</a>.</p>
<p>Cats also seem to be a great source of entertainment. There are <a href="https://tubularinsights.com/2-million-cat-videos-youtube/">two million cat videos on YouTube and counting</a>, and countless internet-famous cats, like Grumpy Cat and Lil’ Bub, each with millions of followers on their social media accounts.</p>
<p><div data-react-class="InstagramEmbed" data-react-props="{"url":"https://www.instagram.com/p/B7T1t99gq2p","accessToken":"127105130696839|b4b75090c9688d81dfd245afe6052f20"}"></div></p>
<p>Despite the popularity of cats, as anyone who has been around a cat knows, reading cats is not always an easy task. One minute they can be seeking your affection and the next they can be swatting at you without any apparent warning. This leads to the question: are cats just jerks or are they simply misunderstood? </p>
<h2>Cats’ body language</h2>
<p>While cats may seem mysterious, their behaviour can help us to understand how they are feeling. The position of a cat’s body, head, ears and tail are all telltale hints. </p>
<p>An <a href="https://doi.org/10.1016%2Fj.jfms.2011.03.012">anxious or fearful cat</a> may crouch down to the ground, arch their back, lower their head and flatten their ears. Fearful or anxious cats may also retreat backwards in avoidance, hide themselves, make their fur stand on edge (piloerection), <a href="https://www.humanesociety.org/resources/cat-chat-understanding-feline-language">growl, hiss, spit</a>, swat or bite.</p>
<p>Conversely, a content cat may approach you with their tail up, with their body and head in a neutral position and their ears forward. When resting, they may tuck their paws in, or lay on their side with their legs stretched out. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/312083/original/file-20200127-81362-g6phtu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/312083/original/file-20200127-81362-g6phtu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/312083/original/file-20200127-81362-g6phtu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=927&fit=crop&dpr=1 600w, https://images.theconversation.com/files/312083/original/file-20200127-81362-g6phtu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=927&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/312083/original/file-20200127-81362-g6phtu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=927&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/312083/original/file-20200127-81362-g6phtu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1165&fit=crop&dpr=1 754w, https://images.theconversation.com/files/312083/original/file-20200127-81362-g6phtu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1165&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/312083/original/file-20200127-81362-g6phtu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1165&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Cats’ emotions can be deciphered through their different behaviours.</span>
<span class="attribution"><a class="source" href="https://blog.doggiedrawings.net/post/120512597686">(Lili Chin)</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>Facial expressions may also be an indicator of how cats are feeling. Researchers have found that <a href="https://doi.org/10.1111/jsap.12283">certain individuals can readily distinguish the images of cats in pain from those of pain-free cats</a>. Despite this, the full range of cat facial expressions, including those made in positive situations, has not received much investigation. </p>
<h2>Most people are poor cat face readers</h2>
<p>As a postdoctoral researcher in animal science, I ran an <a href="https://catdogwelfare.wixsite.com/catfaces">online study</a> in which participants were shown short video clips of cats in various situations. Positive situations were those where cats approached, for example, their owner for treats. Negative situations were those where cats sought to avoid, for example, retreating from a person unknown to them. </p>
<p>The videos were carefully selected based on <a href="https://doi.org/10.7120/09627286.28.4.519">strict behavioural criteria</a> and edited to only show each cat’s face, removing any potential body language or location cues. </p>
<figure>
<iframe src="https://player.vimeo.com/video/211759805" width="500" height="281" frameborder="0" webkitallowfullscreen="" mozallowfullscreen="" allowfullscreen=""></iframe>
<figcaption><span class="caption">An example of a video from the study: here, a cat is kneading in his favoured resting spot, a positive situation.</span></figcaption>
</figure>
<p>More than 6,300 people from 85 countries judged whether the cat in each video was feeling positive or negative. On average, people identified the correct expression 59 per cent of the time. While this score is slightly better than if people had simply guessed, it suggests that many people find the task of reading cat faces challenging. </p>
<figure>
<iframe src="https://player.vimeo.com/video/202460513" width="500" height="281" frameborder="0" webkitallowfullscreen="" mozallowfullscreen="" allowfullscreen=""></iframe>
<figcaption><span class="caption">An example of a video from the study: here, a cat is hiding in the examination room of a veterinary clinic, a negative situation.</span></figcaption>
</figure>
<h2>Cat whisperers</h2>
<p>Although most people were poor cat face readers, a small subset of people (13 per cent) were quite skilled, scoring 15 points or higher out of a possible 20 points.<br>
Individuals in this group are more likely to be women than men. This is not surprising, since research has found that women are generally better at interpreting non-verbal emotional cues; this has been shown with <a href="https://doi.org/10.1111/1467-9450.00193">human babies</a> <a href="https://doi.org/10.1371/journal.pone.0074591">and dogs</a>. </p>
<p>I found “cat whisperers” also tend to have experience working as a veterinarian or veterinary technician. People in these occupations encounter a large number of cats on a daily basis and must learn to interpret their behaviour to recognize illness and avoid injury. </p>
<p>Suprisingly (or not, depending on your personal experience as a cat owner), cat owners are not any better at reading cat faces than people who have never owned a cat. This may be because cat owners learn the intricacies of their own cat through continued interactions, but likely cannot draw on varied experiences when faced with a series of unfamiliar cats. </p>
<h2>Implications for animal welfare</h2>
<p>My work has shown that cats display different facial expressions and that these facial expressions differ depending on how cats are feeling, both positive and negative.</p>
<p>Being able to read and interpret these different facial expressions can help to ensure that cats receive appropriate care. For example, facial expressions can indicate when a cat may be in pain and require treatment. Being able to read cat faces can also improve the bond between cat owners and their cats, through an improved understanding of how their cats may be feeling. </p>
<p>While many people seem to struggle with reading cat faces, some individuals are able to read them well. This suggests that interpreting cat faces is a skill that could improve with training and experience. </p>
<p>Do you think you could be a cat whisperer? You can test your cat-reading abilities by taking <a href="https://catdogwelfare.wixsite.com/catfaces/cat-faces-interactive-quiz">this interactive quiz</a>.</p><img src="https://counter.theconversation.com/content/128686/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Lauren Dawson does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Research suggests that people can learn to read cats’ facial expressions.Lauren Dawson, Postdoctoral fellow, Animal Biosciences, University of GuelphLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1226782019-09-05T20:47:32Z2019-09-05T20:47:32ZCan we really know what animals are thinking?<figure><img src="https://images.theconversation.com/files/290710/original/file-20190903-175663-lqb3z6.jpg?ixlib=rb-1.1.0&rect=48%2C0%2C5422%2C3603&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Animal thought does not have the structure of human language.</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>Sarah, “<a href="https://www.nytimes.com/2019/08/09/opinion/chimpanzee-sarah.html">the world’s smartest chimp</a>,” <a href="https://chimphaven.org/chimp-blog/sarah-anne/">died in July 2019</a>, just before her 60th birthday. For the majority of her life she served as a research subject, providing scientists with a window into the thoughts of homo sapiens’ nearest living relative. </p>
<figure class="align-left zoomable">
<a href="https://images.theconversation.com/files/290746/original/file-20190903-175700-xg3tyb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/290746/original/file-20190903-175700-xg3tyb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/290746/original/file-20190903-175700-xg3tyb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=802&fit=crop&dpr=1 600w, https://images.theconversation.com/files/290746/original/file-20190903-175700-xg3tyb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=802&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/290746/original/file-20190903-175700-xg3tyb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=802&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/290746/original/file-20190903-175700-xg3tyb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1007&fit=crop&dpr=1 754w, https://images.theconversation.com/files/290746/original/file-20190903-175700-xg3tyb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1007&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/290746/original/file-20190903-175700-xg3tyb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1007&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Illustration (by T. W. Wood) of a chimpanzee, disappointed and sulky, from Charles Darwin’s <em>The Expression of the Emotions in Man and Animals</em> (1872).</span>
<span class="attribution"><a class="source" href="https://wellcomecollection.org/works/hbjgkjnj">Wellcome Collection</a></span>
</figcaption>
</figure>
<p>Sarah’s death provides an opportunity to reflect on a foundational question: can we <em>really</em> know what non-human animals are thinking? Drawing on my background as a philosopher, I argue that the answer is no. There are principled limitations to our ability to understand animal thought.</p>
<h2>Animal thought</h2>
<p>There is little doubt that animals think. Their behaviour is too sophisticated to suppose otherwise. But it is awfully difficult to say precisely what animals think. Our human language seems unsuited to express their thoughts. </p>
<p>Sarah exemplified this puzzle. In one famous study, she reliably <a href="https://doi.org/10.1017/S0140525X00076512">chose the correct item to complete a sequence of actions</a>. When shown a person struggling to reach some bananas, she chose a stick rather than a key. When shown a person stuck in a cage, she chose the key over the stick. </p>
<p>This led the study’s researchers to conclude that Sarah had a “theory of mind,” complete with the concepts intention, belief and knowledge. But other researchers immediately objected. They doubted that our human concepts accurately captured Sarah’s perspective. Although hundreds of additional studies have been conducted in the intervening decades, <a href="https://doi.org/10.1111/phc3.12394">disagreement still reigns about how to properly characterize chimpanzees’ mental concepts</a>.</p>
<p>The difficulty characterizing animals’ thoughts does not stem from their inability to use language. After <a href="https://www.abebooks.com/MIND-APE-Premack-David-Ann-James/21359095186/bd">Sarah was taught a rudimentary language</a>, <a href="https://doi.org/10.1080/09515089.2012.670922">the puzzle of what she was thinking simply transformed into the puzzle of what her words meant</a>.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/NBFBbFcixRY?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">BBC Earth: Compiling a chimpanzee dictionary.</span></figcaption>
</figure>
<h2>Words and meanings</h2>
<p>As it turns out, the problem of assigning meanings to words was <a href="https://www.britannica.com/topic/philosophy-of-language">the guiding obsession of philosophy in the 20th century</a>. Among others, it occupied W.V.O. Quine, arguably <a href="https://plato.stanford.edu/entries/quine/">the most influential philosopher of that century’s second half</a>. </p>
<p>A Harvard professor, Quine is famous for imagining what it would take to translate a foreign language — a project he called <a href="http://doi.org/10.4324/9780415249126-U046-1">radical translation</a>. Ultimately, Quine concluded that there would always be multiple equally good translations. As a result, we could never precisely characterize the meaning of the language’s words. But Quine also noted that radical translation was constrained by the structure of language. </p>
<p>Quine imagined a foreign language completely unrelated to any human language, but here, I’ll use German for illustration. Suppose a speaker of the foreign language utters the sentence: “<em>Schnee ist weiss</em>.” Her friends smile and nod, accepting the sentence as true. Unfortunately, that doesn’t tell you very much about what the sentence means. There are lots of truths and the sentence could refer to any one of them. </p>
<p>But suppose there are other sentences that the foreign speakers accept (“<em>Schnee ist kalt</em>,” “<em>Milch ist weiss</em>,” etc.) and reject (“<em>Schnee ist nicht weiss</em>,” “<em>Schnee ist rot</em>,” etc.), sometimes depending on the circumstances (for example, they accept “<em>Schnee</em>!” only when snow is present). Because you now have more evidence and the same words pop up in different sentences, your hypotheses will be more tightly constrained. You can make an educated guess about what “<em>Schnee ist weiss</em>” means. </p>
<p>This suggests a general lesson: insofar as we can translate the sentences of one language into the sentences of another, that is largely because we can translate the words of one language into the words of another.</p>
<p>But now imagine a language with a structure fundamentally unlike that of any human language. How would we translate it? If translating sentences requires translating words, but its “words” don’t map onto our words, we wouldn’t be able to map its sentences onto our own. We wouldn’t know what its sentences mean.</p>
<h2>Unknown grammars</h2>
<p>The thoughts of animals are like the sentences of an unfamiliar language. They are composed from parts in a way that is completely unlike the way that our language is composed from words. As a result, there are no elements in the thoughts of animals that match our words and so there is no precise way to translate their thoughts into our sentences.</p>
<p>An analogy can make this argument more concrete. </p>
<p>What is the correct translation of the Mona Lisa? If your response is that this is an ill-posed question because the Mona Lisa is a painting and paintings can’t be translated into sentences, well… that’s exactly my point. Paintings are composed of colours on a canvas, not from words. So if Quine is right that any halfway decent translation requires matching words to words, we shouldn’t expect paintings to translate into sentences. </p>
<p>But does the Mona Lisa really resist translation? We might try a coarse description such as, “The painting depicts a woman, <a href="https://www.britannica.com/topic/Mona-Lisa-painting">Lisa del Giocondo</a>, smirking slyly.” The problem is that there are ever so many ways to smirk slyly, and the Mona Lisa has just one of them. To capture her smile, we’ll need more detail. </p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/290740/original/file-20190903-175663-115ifo4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/290740/original/file-20190903-175663-115ifo4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/290740/original/file-20190903-175663-115ifo4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=900&fit=crop&dpr=1 600w, https://images.theconversation.com/files/290740/original/file-20190903-175663-115ifo4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=900&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/290740/original/file-20190903-175663-115ifo4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=900&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/290740/original/file-20190903-175663-115ifo4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1131&fit=crop&dpr=1 754w, https://images.theconversation.com/files/290740/original/file-20190903-175663-115ifo4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1131&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/290740/original/file-20190903-175663-115ifo4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1131&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Breaking down Leonardo da Vinci’s Mona Lisa into pixels leads to a reproduction, but not a translation.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<p>So, we might try breaking the painting down into thousands of coloured pixels and creating a micro description such as “red at location 1; blue at location 2; ….” But that approach confuses instructions for reproduction with a translation.</p>
<p>By comparison, I could provide instructions for reproducing the content on the front page of today’s <em>New York Times</em>: “First press the T key, then the H key, then the E key, … .” But these instructions would say something very different from the content of the page. They would be about what buttons should be pressed, not about income inequality, Trump’s latest tweets or how to secure your preschooler’s admission into one of Manhattan’s elite kindergartens. Likewise, the Mona Lisa depicts a smiling woman, not a collection of coloured pixels. So the micro description doesn’t yield a translation.</p>
<h2>Nature of thought</h2>
<p>My suggestion, then, is that trying to characterize animal thought is like trying to describe the Mona Lisa. Approximations are possible, but precision is not.</p>
<p>The analogy to the Mona Lisa shouldn’t be taken literally. The idea is not that animals “think in pictures,” but simply that they do not think in human-like sentences. After all, even those animals, such as Sarah, who manage to laboriously learn rudimentary languages never grasp the rich recursive syntax that three-year-old humans effortlessly master. </p>
<p>Despite having considerable evidence that Sarah and other animals think, we are in the awkward position of being unable to say precisely what they think. Their thoughts are structured too differently from our language. </p>
<p>[ <em>You’re smart and curious about the world. So are The Conversation’s authors and editors.</em> <a href="https://theconversation.com/ca/newsletters?utm_source=TCCA&utm_medium=inline-link&utm_campaign=newsletter-text&utm_content=youresmart">You can read us daily by subscribing to our newsletter</a>. ]</p><img src="https://counter.theconversation.com/content/122678/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jacob Beck receives funding from the Social Sciences and Humanities Research Council of Canada and the Vision: Science to Applications Program, thanks in part to funding from the Canada First Research Excellence Fund.</span></em></p>Can we really know what animals think? A philosopher argues that we can’t, not with any precision.Jacob Beck, Associate Professor, Department of Philosophy, York University, CanadaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1073832019-01-10T13:36:14Z2019-01-10T13:36:14ZCurious Kids: do cats and dogs understand us when we miaow or bark?<figure><img src="https://images.theconversation.com/files/246896/original/file-20181122-182065-2z5tpp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">"I feel like he never hears me..."</span> <span class="attribution"><span class="source">LightField Studios/Shutterstock</span></span></figcaption></figure><p><em>Curious Kids is <a href="https://theconversation.com/africa/topics/curious-kids-36782">a series</a> for children in which we ask experts to answer questions from kids.</em></p>
<p><strong>Do cats and dogs understand humans when they make miaowing or barking noises? (Mila, 11, and Alex, 8)</strong></p>
<p>There’s been <a href="https://www.elsevier.com/books/the-social-dog/kaminski/978-0-12-407818-5">a lot of research</a> about communication between people and domestic animals like dogs and cats. But we don’t yet have the answer to your very interesting question. We don’t know what cats and dogs think or if they understand us when we use their noises.</p>
<p>As a veterinarian and animal behaviourist who studies different kinds of animals, my view is that we’d have to be very good at mimicking miaows and barks if we would really like to be understood by our pets. Our vocal chords are different to theirs, and they can hear that we make different sounds to what they do. </p>
<p>But we do know that <a href="https://www.sciencedirect.com/science/article/pii/S0003347214001262">dogs can definitely distinguish</a> between different people’s voices. They’ll know when it’s Mila who’s talking, and when it’s Alex. They’re also sensitive to your tone of voice. They like high-pitched, friendly tones. And did you know that dogs can learn words?</p>
<p>Rico, a border collie, <a href="https://www.telegraph.co.uk/news/uknews/1464252/Rico-the-collie-that-can-understand-200-words.html">successfully learned</a> more than 200 words representing different items. He could pick the correct item from all the items if asked to “fetch” whichever item. We do not think that he actually learnt the meaning of the words, but he was very good at associating different sounds with different objects. </p>
<p>When it comes to their own “voices”, studies have shown that dogs and cats use <a href="https://www.sciencedirect.com/science/article/pii/B978012407818500005X">different vocal signals</a> to communicate different messages. A high-pitched, repetitive bark, for example, may mean your dog is anxious. A low-pitched bark may mean she’s feeling aggressive. Cats also use certain sounds while hunting and others when relaxing.</p>
<p>But their “voices” are just one way in which dogs and cats communicate. They also use body language and tactile gestures –like coming to you for a pat, or nudging your hand with their nose when they want attention.</p>
<p>In the same way people also communicate using gestures and facial expressions. Research has shown that dogs are better than other species, like wolves, at interpreting our gestures and facial expressions. </p>
<h2>Different communication forms</h2>
<p>If you have dogs, you will have noticed that they’re very sensitive to people’s feelings and our ways of communicating. That’s because <a href="https://books.google.co.za/books?hl=en&lr=&id=4fB7DQAAQBAJ&oi=fnd&pg=PR9&dq=the+domestic+dog+serpell&ots=YOrEQYdRw0&sig=LaoaGv_nRjvuwaSt2j-ABs39G7k#v=onepage&q=the%20domestic%20dog%20serpell&f=false">they’ve evolved</a> to live in close proximity with people. </p>
<p>Cats are not naturally social animals, but they also communicate with us and can be highly perceptive about what mood you’re in and how you’re feeling.</p>
<p>All of this is important when you think about the best ways to communicate with your dogs and cats. Since visual signals are really important to them, it’s likely that they consider our body language, before listening to our sounds, so they can decide what it is that we’re communicating. </p>
<p>Humans use language as our main means of communication. That’s why we tend to want our pets to respond to our words. They certainly can learn to do this, as we have seen with Rico and thousands of other examples. </p>
<p>However, in many instances, they are actually responding to our body language cues and not the verbal cues we are using. </p>
<p>Take for example telling your dog to sit: most people say the word “sit”, and at the same time point their finger at the dog. They think the dog sits because they are saying “sit” – but it’s actually responding to the finger pointing. If you say the word “sit” without the hand gesture your dog will, in many cases, not sit. This proves how important body language is to dogs.</p>
<p>I would encourage everyone who owns pets, especially dogs, to learn more about their body language so that we can better interpret what they are trying to say to us. A common perception, for example, is that when a dog’s tail is wagging it is always friendly. This is only true when the wag of the tail is wide and accompanied by a relaxed body. A dog whose tail is up in the air, with only the tip wagging, is actually saying “go away” and not “let’s play”. </p>
<p>The more time you spend learning your pets’ body language and getting to know what different gestures mean, the more easily you’ll be able to communicate with them – and you won’t have to “miaow” or bark to do that.</p>
<p><em>Hello, curious kids! Have you got a question you’d like an expert to answer? Ask an adult to send your question to africa-curiouskids@theconversation.com. Please tell us your name, age, and which city you live in. We won’t be able to answer every question but we will do our best.</em></p><img src="https://counter.theconversation.com/content/107383/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Quixi Sonntag does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>When it comes to their own “voices”, studies show that cats and dogs use different vocal signals to communicate different messages.Quixi Sonntag, Lecturer in animal behaviour and welfare, University of PretoriaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1040252018-10-15T10:28:31Z2018-10-15T10:28:31ZEating royal poop improves parenting in naked mole-rats<figure><img src="https://images.theconversation.com/files/240439/original/file-20181012-109219-gvip1m.jpg?ixlib=rb-1.1.0&rect=459%2C23%2C3166%2C2112&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Hormone signals help ready worker mole-rats to treat pups as their own.</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/naked-mole-rat-heterocephalus-glaber-parenting-92428243">belizar/Shutterstock.com</a></span></figcaption></figure><p>Have you ever seen a picture of a mother dog caring for an unusual baby, like a kitten? This sort of animal adoption story is an example of a phenomenon known as <a href="https://doi.org/10.1002/dneu.22465">alloparenting</a>: care provided to offspring that are not genetically related. </p>
<p>We humans may toss around the phrase “It takes a village to raise a child,” but there are cases in the animal world where this is more literally true. Naked mole-rats, wrinkly mammals of the East African desert, offer an example of the whole “village” cooperating to raise offspring.</p>
<p>Each individual naked mole-rat <a href="https://doi.org/10.1126/science.7209555">has a specific job</a>. Like in a honeybee hive, a naked mole-rat colony has one queen, whose job it is to reproduce. There are just a few sexually reproductive males, who mate with the queen. All the others, both male and female, are either soldiers that protect the colony or workers that forage for food, dig tunnels and care for the queen’s offspring, known as pups. </p>
<p>Until now, no one had a physiological explanation for why naked mole-rat workers care for pups that aren’t their own. Normally when a mom gives birth, estrogen levels are high and progesterone levels drop, <a href="https://doi.org/10.1016/j.yfrne.2014.11.007">resulting in maternal behaviors</a> such as feeding or grooming. In many unusual adoption stories, like that of the mother dog caring for a kitten, the adoptive mom will have recently given birth to her own offspring – meaning her hormone levels have left her primed and ready to care for offspring, even those that aren’t her own.</p>
<p>But female naked mole-rat workers have <a href="https://doi.org/10.1530/jrf.0.0880559">lower levels</a> of these hormones because their reproductive organs never mature. How, then, could the naked mole-rat workers be such great parents? The answer to this question involves a web of workers, queens, hormones and poop-eating.</p>
<h2>Sending a message…via poop?</h2>
<p><a href="https://scholar.google.com/citations?user=FjZF4HQAAAAJ&hl=en&oi=ao">As a biologist</a>, I’m interested in understanding how chemicals in the body can cause changes in behavior. In <a href="http://sites.tufts.edu/kaolab/">my lab</a> I study the role of neurotransmitters, the brain’s chemical messengers, in vocal communication.</p>
<p>Recently, researchers in Japan noticed that worker naked mole-rats were faster to respond to pup calls and spent more time in the area where the calls originated after a queen gave birth. Naked mole-rats <a href="https://doi.org/10.1111/j.1439-0310.2007.01371.x">can vocalize</a> to communicate, but their <a href="https://doi.org/10.1002/cne.903310311">hearing is poor</a>.</p>
<p>It looked like something about the queen’s reproductive stage was affecting the workers’ behavior. But what was going on? It’s unlikely they were communicating solely through vocalizations due to their poor hearing. Could there be some kind of chemical communication at play?</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/240426/original/file-20181012-109239-qk7c84.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/240426/original/file-20181012-109239-qk7c84.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/240426/original/file-20181012-109239-qk7c84.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=481&fit=crop&dpr=1 600w, https://images.theconversation.com/files/240426/original/file-20181012-109239-qk7c84.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=481&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/240426/original/file-20181012-109239-qk7c84.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=481&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/240426/original/file-20181012-109239-qk7c84.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=604&fit=crop&dpr=1 754w, https://images.theconversation.com/files/240426/original/file-20181012-109239-qk7c84.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=604&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/240426/original/file-20181012-109239-qk7c84.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=604&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Naked mole-rats eat roots and tubers…and also feces.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Naked_Molerats_004.jpg">Ltshears/Wikimedia Commons</a></span>
</figcaption>
</figure>
<p>Since naked mole-rats commonly eat poop to get any leftover nutrients, the researchers wondered whether the queen’s pregnant poop might contain a chemical that, when eaten, would affect the workers’ behaviors. Maybe pooped-out estrogen from the queen is a way for her to communicate with the workers, preparing them for parenthood.</p>
<p><a href="https://doi.org/10.1073/pnas.1720530115">They designed a series of experiments</a> to investigate whether eating a pregnant queen’s estrogen-rich poop would make female workers more responsive and attentive parents to the colony’s pups.</p>
<h2>Untangling the estrogen connection</h2>
<p>First, the researchers fed worker naked mole-rats poop from pregnant and nonpregnant queens. They wanted to see if there would be differences in how the two groups of workers responded to pup calls. And indeed, naked mole-rats that ate the pregnancy poop were more responsive and attentive parents than those fed regular queen poop. </p>
<p>Then the researchers turned their attention to what was in the poop itself. The pregnant queen’s poop had high concentrations of estrogen and progesterone – two hormones commonly <a href="https://doi.org/10.1016/S0169-5347(00)01972-8">associated with parental behaviors</a>. And during the queen’s pregnancy, workers had higher concentrations of estrogen in their own poop, too.</p>
<p>To be sure the increases in workers’ estrogen levels stemmed from the hormones in the pregnancy poop, and not just from being around a pregnant queen, the researchers mixed up a batch of “artificial poop.” They formulated the poop with estrogen and progesterone concentrations similar to what they’d found excreted by the pregnant queen. Sure enough, workers’ estrogen concentrations rose after they dined on this poop cocktail. Now the researchers were confident that the estrogen was transferring from the queen to the workers via her pregnant poop. </p>
<p>The research team then wanted to nail down the connection between the hormones and the behavior. So, they fed workers either normal nonpregnant queen poop, or nonpregnant queen poop supplemented with estrogen. Workers that ate the estrogen-enhanced poop showed levels of responsiveness and attentiveness to pup calls similar to those that had originally inspired the researchers to pursue these experiments. </p>
<p>It’s important to note that this study was carried out in a colony of naked mole-rats born and raised in the lab. It would be interesting to repeat this set of experiments in the field, and see if estrogen in poop causes the same behavioral changes in wild naked mole-rat workers.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/240440/original/file-20181012-109230-47icc8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/240440/original/file-20181012-109230-47icc8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/240440/original/file-20181012-109230-47icc8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=404&fit=crop&dpr=1 600w, https://images.theconversation.com/files/240440/original/file-20181012-109230-47icc8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=404&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/240440/original/file-20181012-109230-47icc8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=404&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/240440/original/file-20181012-109230-47icc8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=508&fit=crop&dpr=1 754w, https://images.theconversation.com/files/240440/original/file-20181012-109230-47icc8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=508&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/240440/original/file-20181012-109230-47icc8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=508&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Part of good parenting for naked mole-rats is keeping the pups warm and safe.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/naked-mole-rat-colony-underground-chambre-1035296629">Neil Bromhall/Shutterstock.com</a></span>
</figcaption>
</figure>
<h2>Estrogen in poop: Multiple layers of communication</h2>
<p>The changes in the behavior of workers after ingesting estrogen-laden poop suggests that the hormone not only served as a way to make the naked mole-rats better parents, but also as a way for the queen to communicate with her workers. In this way, the estrogen in the queen’s poop works on two levels: It gives workers a heads-up about the queen’s pregnant state and also improves the workers’ response to pup communications.</p>
<p>Many studies on chemical communication between mammals focus on <a href="https://doi.org/10.1111/j.1749-6632.1998.tb10596.x">pheromones</a>: odor signals secreted by other individuals that affect one’s own behavior. Scientists have primarily regarded estrogen as a hormone that affects the behavior of the individual producing it. However, this study provides insight into how estrogen produced by others can not only be a means of communicating, but also a factor that influences one’s own behaviors.</p><img src="https://counter.theconversation.com/content/104025/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Gina Mantica does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Worker naked mole-rats take care of their colony’s young even though they aren’t the pups’ actual parents. New research suggests the queen gets them ready via hormones in her poop.Gina Mantica, Ph.D. Candidate in Biology, Tufts UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/959902018-05-08T14:17:48Z2018-05-08T14:17:48ZStudying chimpanzee calls for clues about the origins of human language<figure><img src="https://images.theconversation.com/files/218089/original/file-20180508-34006-g309sg.jpg?ixlib=rb-1.1.0&rect=0%2C20%2C952%2C672&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Nisarg Desai observes wild chimps known as Sandi, Ferdinand and Siri in Tanzania.</span> <span class="attribution"><span class="source">Michael Wilson</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span></figcaption></figure><p>Freud, Wilkie and the other chimpanzees peacefully fed and rested in the sun-dappled Tanzanian forest. Mzee Hilali stood next to me, writing notes on the chimpanzees’ behavior, as he had been doing for over 30 years as a field assistant for <a href="http://www.janegoodall.org/">Jane Goodall’s long-term study at Gombe National Park</a>.</p>
<p>Suddenly, a strange, high-pitched call sounded from where some other chimpanzees were feeding, about a hundred meters from us. Hilali turned to me, and with a little laugh, said, “Nyoka.” This was the Swahili word for “snake.” </p>
<p>Freud climbed down from his tree and walked quickly toward where the call had sounded, with Hilali following close behind. As I slowly made my way through the undergrowth to catch up with them, Hilali called to me: “Chatu!” “Python!”</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/217732/original/file-20180504-166877-17honyi.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/217732/original/file-20180504-166877-17honyi.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/217732/original/file-20180504-166877-17honyi.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/217732/original/file-20180504-166877-17honyi.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/217732/original/file-20180504-166877-17honyi.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/217732/original/file-20180504-166877-17honyi.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/217732/original/file-20180504-166877-17honyi.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/217732/original/file-20180504-166877-17honyi.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A glint of snake scales in the vine tangle.</span>
<span class="attribution"><span class="source">Michael Wilson</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>When I caught up with Hilali, he was pointing to a tangled mass of leaves and vines on the forest floor. I looked closely – most of the snake lay hidden from view, but the one visible stretch of black and tan scaly hide was too big to be anything but a python. </p>
<p>From years of experience, Mzee Hilali knew instantly that this particular chimp call meant they’d found a snake. Does this mean that chimpanzees have a “word” for snake? Do chimpanzees have a language of their own? <a href="https://scholar.google.com/citations?user=cvK1qxAAAAAJ&hl=en&oi=sra">I’ve been working</a> with a team of students and Tanzanian field assistants to record and analyze chimpanzee vocalizations in an effort to answer questions like this. Ultimately we hope to learn more about how human language first evolved.</p>
<h2>Clues to the origins of language</h2>
<p>Chimpanzees are among human beings’ <a href="http://humanorigins.si.edu/evidence/genetics">closest living relatives</a>, and they share with us many unusual traits. Like humans, chimps <a href="https://doi.org/10.1038/srep34783">make and use tools</a>; join together in groups to <a href="https://news.nationalgeographic.com/2018/04/chimpanzees-monkeys-brains-animals-predators/">hunt animals like monkeys</a>; <a href="https://kibalechimpanzees.wordpress.com/2012/01/06/why-do-chimpanzees-fight-with-their-neighbors/">defend group territories</a>; and sometimes <a href="http://blog.michael-lawrence-wilson.com/2014/09/19/chimpanzee-violence/">gang up on and kill their enemies</a>. </p>
<p>One trait that seems to set humans apart from every other species, however, is a <a href="http://www.bbc.com/future/story/20121016-is-language-unique-to-humans">fully developed language</a>. <a href="https://www.khanacademy.org/science/biology/behavioral-biology/animal-behavior/a/animal-communication">Other animals communicate</a>, but only humans appear able to talk about an unlimited variety of topics. Language enables us to make plans, negotiate with and teach one another.</p>
<p>How and why language evolved remains a mystery. Much of the evidence of human evolution comes from fossils, but fossil bones don’t tell us much about soft tissues or the sounds early human ancestors made. <a href="https://doi.org/10.3378/027.083.0202">Studying the communication patterns of our living relatives</a> can help solve the mystery. </p>
<p>If some features of chimpanzee communication resemble language, we can study chimpanzees further to find clues for why those features evolved. If chimpanzee communication doesn’t share much in common with human language, then the key steps in language evolution must have occurred after our lineages separated (around <a href="https://doi.org/10.1073/pnas.1600374113">7.9 million years ago</a>) for reasons unique to our human lineage.</p>
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<a href="https://images.theconversation.com/files/217982/original/file-20180507-46341-ghx3q3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/217982/original/file-20180507-46341-ghx3q3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/217982/original/file-20180507-46341-ghx3q3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=567&fit=crop&dpr=1 600w, https://images.theconversation.com/files/217982/original/file-20180507-46341-ghx3q3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=567&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/217982/original/file-20180507-46341-ghx3q3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=567&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/217982/original/file-20180507-46341-ghx3q3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=713&fit=crop&dpr=1 754w, https://images.theconversation.com/files/217982/original/file-20180507-46341-ghx3q3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=713&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/217982/original/file-20180507-46341-ghx3q3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=713&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Michael Wilson with microphone during his dissertation research in Kibale National Park, Uganda, waiting for the chimp known as Light Brown to vocalize.</span>
<span class="attribution"><span class="source">Becky Sun</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
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<h2>Recording in the forest</h2>
<p>To investigate chimp communication, my colleagues and I follow chimpanzees through the forest as they go about their lives. We carry a hand-held “shotgun” microphone and a digital recorder, waiting for them to call.</p>
<p>Usually we pick a particular chimp to follow each day, trying to get equal numbers of calls per individual. In addition to recording new calls, we’ve been working to build an archive of recordings from other researchers, going back to the 1970s. The archive currently contains over 71 hours of recordings.</p>
<p>Snake alarm calls are intriguing, but because chimps don’t encounter large snakes very often, it is hard to do a systematic study of them. (<a href="https://scholar.google.com/citations?user=sbOSgw0AAAAJ&hl=en&oi=ao">Cathy Crockford</a> and colleagues have done some interesting experiments, though, <a href="https://doi.org/10.1007/s10071-014-0827-z">playing back recordings of these calls</a> to see how chimpanzees respond and <a href="https://doi.org/10.1016/j.cub.2011.11.053">presenting them with model snakes</a>). One thing chimpanzees do every single day, though, is eat. Chimpanzees spend most of their time looking for food and eating it. And when they find food, they often give a particular kind of call: the rough-grunt.</p>
<p><audio preload="metadata" controls="controls" data-duration="2" data-image="" data-title="A chimpanzee rough-grunt." data-size="24334" data-source="" data-source-url="" data-license="" data-license-url="">
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A chimpanzee rough-grunt.
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<p>Biologist <a href="https://scholar.google.com/citations?user=pezyHCAAAAAJ&hl=en&oi=sra">Lisa O'Bryan</a> <a href="https://blog.nationalgeographic.org/2013/07/08/uncovering-the-secrets-of-chimpanzee-communication/">studied rough-grunt calls</a> for her dissertation research with me. They vary from low, noisy grunts to higher-pitched calls. Some researchers have proposed an intriguing possibility: Maybe chimpanzees make <a href="https://doi.org/10.1016/j.cub.2005.08.068">distinct kinds of rough-grunt calls in response to particular foods</a>, rather like words that name certain food items.</p>
<p>But Lisa has found that when eating any one kind of food, chimpanzees can produce a range of different rough-grunts. Rough-grunts thus tell other chimps that the caller is eating, but <a href="https://doi.org/10.1121/1.5035852">they don’t say what’s for dinner</a>.</p>
<p>Just as a particular alarm call informs others that a snake has been found, the thin, wavering tones of a copulation scream announce that a mating has just taken place. </p>
<p><audio preload="metadata" controls="controls" data-duration="1" data-image="" data-title="A chimpanzee copulation scream." data-size="14930" data-source="" data-source-url="" data-license="Author provided" data-license-url="">
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A chimpanzee copulation scream.
<span class="attribution"><span class="license">Author provided</span><span class="download"><span>14.6 KB</span> <a target="_blank" href="https://cdn.theconversation.com/audio/1162/nl201-cop-scream.mp3">(download)</a></span></span>
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<p>Why female chimpanzees sometimes give such a scream just as they finish mating remains unknown. Because the data collected by Mzee Hilali and other field assistants since the 1970s <a href="https://evolutionaryanthropology.duke.edu/research/pusey-lab/jane-goodall-institute-research-center">have been entered into a computer database</a>, we can readily examine thousands of different mating events.</p>
<p>My student <a href="https://cbs.umn.edu/academics/departments/eeb/graduate/graduate-student-directory#Massaro">Tony Massaro</a> has been analyzing these data to try to tease out what factors make females more likely to produce these calls. Such calls aren’t particularly word-like, but they do play an important role in communication. Like many wordless sounds that people make – think laughter, screams and crying – listeners hearing the sounds can infer quite a bit about the caller’s situation.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/BF0qIy4ZnSU?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Jane Goodall demonstrates how chimpanzees pant-hoot.</span></figcaption>
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<p>When Jane Goodall gives public talks, <a href="https://www.youtube.com/watch?v=BF0qIy4ZnSU">she often begins by giving a pant-hoot</a>: a loud call that begins with an introduction, followed by a build-up, a climax and a let-down. Pant-hoots are loud and enable chimpanzees to communicate over long distances through the forest.</p>
<p>Previous studies have found differences in the pant-hoots calls from different regions. For example, the pant-hoots from Gombe sound a bit different from those made by chimpanzees in Mahale, 160 km away. When I played recordings of a single Mahale pant-hoot call to chimpanzees in Kibale Forest, Uganda, the Kibale chimpanzees <a href="https://doi.org/10.1006/anbe.2000.1706">acted as if they had just heard an intruder</a>. If they were in a group with three or more males, they gave a loud vocal response and rapidly moved towards the speaker.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/bd1bO-nK6NQ?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Response to simulated intruder with many males present.</span></figcaption>
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<p>If they were in a group with only one or two males present, though, they stayed quiet, and if they approached, did so slowly and cautiously.</p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/4bY7GjmlGRQ?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Response to simulated intruder with only two males present.</span></figcaption>
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<p>For chimpanzees, correctly telling friend from foe is a matter of life or death, so it would make sense for chimpanzees in neighboring groups to have distinctive pant-hoot calls.</p>
<p>Cathy Crockford and colleagues found that pant-hoots from different communities within Taï Forest, Côte d'Ivoire, <a href="https://doi.org/10.1111/j.1439-0310.2004.00968.x">also sound distinct</a>. If such group-level differences result from vocal learning, they would be rather like dialects in human languages.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/217980/original/file-20180507-46347-12kfxla.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/217980/original/file-20180507-46347-12kfxla.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/217980/original/file-20180507-46347-12kfxla.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=892&fit=crop&dpr=1 600w, https://images.theconversation.com/files/217980/original/file-20180507-46347-12kfxla.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=892&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/217980/original/file-20180507-46347-12kfxla.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=892&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/217980/original/file-20180507-46347-12kfxla.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1121&fit=crop&dpr=1 754w, https://images.theconversation.com/files/217980/original/file-20180507-46347-12kfxla.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1121&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/217980/original/file-20180507-46347-12kfxla.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1121&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">Nisarg going over how to use the recording equipment with Hashimu and Nasibu.</span>
<span class="attribution"><span class="source">Michael Wilson</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
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</figure>
<p>My student <a href="https://cla.umn.edu/about/directory/profile/desai054">Nisarg Desai</a> has been testing whether this is also the case at Gombe. We’ve been working with a team of Tanzanian field assistants, Hashimu Issa Salala and Nasibu Zuberi Madumbi, to record calls from the Mitumba and Kasekela chimpanzees, and are starting to test for differences between groups.</p>
<p>We are in the early stages of this analysis.</p>
<h2>From calls to language isn’t a clear path</h2>
<p>Chimpanzees might be capable of some degree of vocal learning, but I’m struck by how subtle the differences in pant-hoot calls are from place to place. Chimpanzees make lots of different calls – pant-hoots, pant-barks, waa-barks, pant-grunts, rough-grunts, and so on – but across Africa, all chimpanzees produce a pretty similar set of calls in similar circumstances. In this respect, chimpanzee calls resemble human sounds like laughter and crying more than they resemble human words, which can vary drastically from place to place.</p>
<p>Chimpanzees communicate effectively with their various sounds, but in ways quite similar to those of other nonhuman primates. This suggests that our common ancestor with chimpanzees also had a fairly typical repertoire of vocal communication for a nonhuman primate. The really big changes in human language – such as a lifelong ability to learn to make entirely new sounds and a rich symbolic meaning of such sounds – likely evolved later, for reasons that we still don’t understand.</p><img src="https://counter.theconversation.com/content/95990/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Michael Wilson's research on chimpanzee vocal communication has been funded by the National Science Foundation and a McKnight Land-Grant Professorship and a Talle Faculty Research Award from the University of Minnesota.</span></em></p>Do chimpanzee talk to each other? Scientists follow and record chimpanzees in the wild to find out – and to fill in details about how human language might have evolved.Michael Wilson, Associate Professor of Ecology, Evolution and Behavior, University of MinnesotaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/860082017-10-19T15:15:43Z2017-10-19T15:15:43ZAre dogs trying to tell us something with their expressions?<figure><img src="https://images.theconversation.com/files/191047/original/file-20171019-1086-18i6bqe.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>Dogs have been part of human social groups for at least <a href="https://www.ncbi.nlm.nih.gov/pubmed/24233726">30,000 years</a>. So it’s not unreasonable to suppose that we might have had some influence on their behaviour, and perhaps their understanding, during that time. We certainly know that dogs have developed ways to communicate with us, for example by whining when they are distressed or barking to <a href="http://www.sciencedirect.com/science/article/pii/S1558787807001785">alert us to intruders</a>.</p>
<p>Many dog owners would probably say their pets can even tell us things using facial expressions, just like humans do. But is that really true? Perhaps they are just showing emotion without meaning to communicate (just like humans also sometimes do). New research published in the journal <a href="http://nature.com/articles/doi:10.1038/s41598-017-12781-x">Scientific Reports</a> suggests it might be, but there are still reasons to be sceptical.</p>
<p>In a rather elegant experiment, the researchers set up four scenarios. They offered a dog food (a guaranteed way to get their interest) while the human handler was facing towards and also away from the dog. They also had the handler face towards and away from the dog without offering food. They found that the animals showed facial expressions more often when the handler was facing towards them than away, regardless of whether or not food was involved.</p>
<p>Until now, there has been little work on whether or not facial expressions in dogs are involuntary. You might be able to see when a dog’s happy, angry or sad from their face, but that doesn’t mean they are purposefully trying to tell you how they felt.</p>
<p><a href="http://nature.com/articles/doi:10.1038/s41598-017-12781-x">The new paper</a> suggests that the expressions may be a means of communicating something to the person. It is certain that the expression is more frequently displayed when the human is facing towards the dog, even though the handler did not look directly at the dog during the trial, and that humans respond to that expression.</p>
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<img alt="" src="https://images.theconversation.com/files/191049/original/file-20171019-1086-702bxp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/191049/original/file-20171019-1086-702bxp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/191049/original/file-20171019-1086-702bxp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/191049/original/file-20171019-1086-702bxp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/191049/original/file-20171019-1086-702bxp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/191049/original/file-20171019-1086-702bxp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/191049/original/file-20171019-1086-702bxp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">If I make this face, will you stop shouting?</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
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<p>That dogs are able to understand when a person is paying attention to their behaviour <a href="https://www.ncbi.nlm.nih.gov/pubmed/16893253">is well documented</a>. We also know that dogs show different facial expressions when in the presence of humans, especially in the case of that <a href="https://www.ncbi.nlm.nih.gov/pubmed/16893253">“guilty” look</a> that every dog owner knows. That particular expression doesn’t actually mean they are feeling guilty. It’s more an attempt to appease the owner who is angry for some, to the dog, unknown reason. </p>
<p>But there are some questions about the particular facial expressions the dogs made in the new study that mean the evidence isn’t conclusive. For example, one of the expressions the authors noticed was the raising of the <a href="http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0082686">inner end of the eyebrows</a>. This increases the size of the eyes and makes the dog look more puppy-like. </p>
<p>Studies have shown that humans prefer animals that <a href="http://www.sciencedirect.com/science/article/pii/0003347277900720?via%3Dihub">look like infants</a>. This explains the popularity of breeds with short noses and large eyes, such as boxers and pugs. Dogs that raise their eyebrows more frequently seem to be <a href="http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0082686">more popular with people</a> than those that don’t. This could have led to the breeding of dogs that are more likely to show these more attractive expressions alongside those that have childlike anatomical features.</p>
<h2>Tongue wagging</h2>
<p>Another important indicator that the authors noted was when the dogs showed their tongues. Unfortunately, the researchers didn’t separate tongue movements that <a href="http://www.sciencedirect.com/science/article/pii/S1558787816302490">indicate stress</a>, such as licking the nose or lips, which can be an appeasing signal, from those that indicate pleasure, anticipation or excitement, such as panting or hanging the tongue out of the mouth. Without this distinction it is difficult to draw conclusions about the emotional state of the dogs.</p>
<p><a href="http://psycnet.apa.org/doiLanding?doi=10.1037%2F0735-7036.115.2.122">Previous research</a> also suggests that dogs are aware of when a human is paying attention to them and may change their behaviour accordingly. It is possible that these dogs, aware that the human is facing them felt a level of anticipation, excitement and possibly some anxiety which affected their facial expression. The fact that the food produced no extra interest when the person was turned towards the dog or away from them, could be influenced by the fact that the dog was not actually given the food.</p>
<p>The authors suggest that the dog’s facial expressions may be partly a result of their emotional state and partly an attempt to actively communicate with the handler. Without any evidence about the effect of the expression on the behaviour of the handler, it is <a href="http://www.sciencedirect.com/science/article/pii/0022519361900327">difficult to say if that is true</a>. </p>
<p>If further research could make distinctions between the type of tongue movements involved in these expressions, as well as the raising of the eyebrows, we might be able to say with more certainty. But whatever the outcome, many dog owners will probably continue to swear their pets are trying to tell them something.</p><img src="https://counter.theconversation.com/content/86008/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jan Hoole does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>It can be easy to tell how dogs are feeling but new evidence suggests they’re also trying to communicate.Jan Hoole, Lecturer in Biology, Keele UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/710492017-01-11T12:51:12Z2017-01-11T12:51:12ZHow to talk to your dog – according to science<figure><img src="https://images.theconversation.com/files/152389/original/image-20170111-16028-1szz7g7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Are you listening?</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>Dogs are special. Every dog owner knows that. And most dog owners feel their dog understands every word they say and every move they make. Research over the last two decades shows dogs really can understand human communication in ways no other species can. But a new study confirms that if you want to train your new puppy, you should be speaking to it in a certain way to maximise the chances that it follows what you’re saying.</p>
<p>There is already quite a lot of research evidence showing that the way we communicate to dogs is different from the way we communicate to other humans. When <a href="http://science.sciencemag.org/content/296/5572/1435">we talk to dogs</a>, we use what is called “<a href="https://www.cambridge.org/core/journals/journal-of-child-language/article/doggerel-motherese-in-a-new-context/79FF5CF27F5B78316BBD8976A309A46B">dog directed speech</a>”. This means we change the structure of our sentences, shortening and simplifying them. We also tend to speak with a higher pitch in our voices. We also do this when we are not sure we are understood or when talking to very young infants. </p>
<p>A new study has shown we use an even higher pitch when talking to puppies, and that this tactic really does help the animals to pay attention more. The research, published in the journal <a href="http://rspb.royalsocietypublishing.org/lookup/doi/10.1098/rspb.2016.2429">Proceedings of the Royal Society B</a>, showed that talking to puppies using dog-directed speech makes them react and attend more to their human instructor than regular speech.</p>
<p>To test this, the researchers use so-called “play back” experiments. They made recordings of humans repeating the phrase “Hi! Hello cutie! Who’s a good boy? Come here! Good boy! Yes! Come here sweetie pie! What a good boy!”. Each time, the speaker was asked to look at photos of either puppies, adult dogs, old dogs or at no photos. Analysing the recordings showed the volunteers did change how they spoke to different aged dogs.</p>
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<p>The researchers then played the recordings back to several puppies and adult dogs and recorded the animals’ behaviour in response. They found the puppies responded more strongly to the recordings made while the speakers looked at pictures of dogs (the dog-directed speech).</p>
<p>The study didn’t find the same effect applied for adult dogs. But <a href="http://linkinghub.elsevier.com/retrieve/pii/S0960982211013935?via=sd&cc=y">other studies</a> that recorded dogs’ reactions to the human voice in live interactions, including <a href="http://www.eva.mpg.de/documents/Wiley-Blackwell/Kaminski_How-dogs_DevScience_2012_1563374.pdf">work I have done</a>, have suggested dog-directed speech can be useful for communicating with canines of any age. </p>
<h2>Following the point</h2>
<p>It’s also been proven (and most dog-owners will tell you) that we can communicate with dogs through physical gestures. From puppy age on, dogs respond to human gestures, such as pointing, in ways other species can not. The <a href="http://science.sciencemag.org/content/298/5598/1634">test is very simple</a>. Place two identical cups covering small pieces of food in front of your dog, making sure it cannot see the food and doesn’t have any information about the contents of the cups. Now point to one of the two cups while establishing eye contact with your dog. Your dog will follow your gesture to the cup you pointed to and explore the cup, expecting to find something underneath.</p>
<p>This is because your dog understands that your action is an attempt to communicate. This is fascinating because not even human’s closest living relatives, chimpanzees, seem to understand that humans communicate intent in this situation. <a href="http://linkinghub.elsevier.com/retrieve/pii/S096098220300263X?via=sd">Nor do wolves</a> – dog’s closest living relatives – even if they are raised like dogs in a human environment.</p>
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<p>This has led to the idea that dogs’ skills and behaviours in this area are actually <a href="https://www.researchgate.net/publication/287265047_The_Social_Dog_History_and_Evolution">adaptations to the human environment</a>. That means living in close contact with humans for over 30,000 years has led dogs to evolve communication skills that are effectively equal to those of human children.</p>
<p>But there are significant differences in how dogs understand our communication and how children do. The theory is that dogs, unlike children, view human pointing as some <a href="http://www.sciencedirect.com/science/article/pii/S0023969013000325">kind of mild command</a>, telling them where to go, rather than a way of transferring information. When you point for a child, on the other hand, they will think you are informing them about something.</p>
<p>This ability of dogs to recognise “spatial directives” would be the perfect adaptation to life with humans. For example, dogs have been used for thousands of years as a kind of “social tool” to help with herding and hunting, when they had to be guided over a great distance by gestural instructions. The latest research affirms the idea that not only have dogs developed an ability to recognise gestures but also a special sensitivity to the human voice that helps them identify when they need to respond to what’s being said.</p><img src="https://counter.theconversation.com/content/71049/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Juliane Kaminski consults for Dognition.</span></em></p>New research confirms puppies respond better when we talk to them in a certain way.Juliane Kaminski, Senior lecturer in psychology, University of PortsmouthLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/438092015-06-25T16:01:28Z2015-06-25T16:01:28ZHow the parrot got its chat (and its dance moves)<figure><img src="https://images.theconversation.com/files/86375/original/image-20150625-12984-1416ek3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Who's a clever boy then?</span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/dcoetzee/3572948635/in/photolist-6rJi9F-kVv1TF-igHgQJ-39ywib-6hw5Qm-6rNr4b-6gK5Pj-6rNrvm-6M2oLB-ikGD2w-6jK7Q8-pjELKc-m7a8-6rN6yM-8YVpSB-r6vnmG-dPreJn-dS6Z3q-56Ge12-di9Sz7-45fyiw-a24nei-4MTVHq-8oxq6N-dtVDZV-6XW4tM-6wjLVd-dtQxUf-6rNrC5-gGYJF3-akFRqZ-3DqxnW-2CSkKB-uHsWTU-diY6BN-7VVKgn-6rJiua-9pYftu-6jK7L2-6wjLR1-du2eXy-pUdM1s-defmFG-D59Pb-aCNwi8-bJKhXg-94f7sQ-6VjrDy-9D3HK5-gCamK9"> D Coetzee/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p>Many animals – including seals, dolphins and bats – <a href="http://news.bbc.co.uk/1/hi/sci/tech/3430481.stm">are able to communicate vocally</a>. However, parrots are among a select few that can spontaneously imitate members of another species. A study has now pinpointed <a href="http://www.eurekalert.org/pub_releases/2015-06/du-sha062215.php">the region in the brain that may be allowing this to happen</a> – the region that is also involved in controlling movement. The finding could perhaps also explain the fact that parrots, just like humans, can talk and dance. </p>
<p>We know that birds that can sing, including parrots, have distinct centres in their brain supporting vocalisations, called the “cores”. But, exclusively in parrots, around these there are outer rings, or “shells”. Surrounding this is a third region supporting movement. This is an older pathway that is shared by vertebrates. To find out more about what the unique shell system actually does, the research team analysed the expression of genes in these pathways in nine different species of parrot. They focused on ten genes that we know to be more active in the song regions of birds’ brains compared to other parts of the brain.</p>
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<p>They found that parrots, when compared to other birds, have a complex pattern of specialised gene expression in all three parts of its brain. That means that most of the vocal learning that is specific to parrots, such as imitation, must be taking place in the shell region and the part of the brain that controls movements. This is surprising, as previous work had assumed that only the dedicated core system would be involved in vocal learning and that the shells had nothing to do with talking. </p>
<p>My own research has shown that it is the connections between brain regions controlling cognitive and motor skills that <a href="http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=9167752&fileId=S186698080000034X">support language in humans</a>.</p>
<p>The researchers also examined songbirds and hummingbirds and found that the shell regions were indeed unique to the parrots. However, they said future research would have to clarify the exact mechanisms involved in imitating.</p>
<h2>Imitation game</h2>
<p>That this shell system is observed in so many species of parrot – including in Keas, the most ancient species known – suggests that the vocalisation abilities evolved around 29m years ago. For comparison, that is more or less the time when humans’ ancestors are believed to have branched off from other primates. </p>
<p>The researchers hypothesise that this shell structure evolved after the core system for singing in birds was duplicated in the brain, with the shell centre developing new functions such as mimicking. So studying the shell structure in parrots could help us identify other <a href="http://www.ncbi.nlm.nih.gov/books/NBK207176/">mysterious duplications</a> that could have led to certain brain functions in humans.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/86356/original/image-20150625-13002-1n1nb2a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/86356/original/image-20150625-13002-1n1nb2a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=480&fit=crop&dpr=1 600w, https://images.theconversation.com/files/86356/original/image-20150625-13002-1n1nb2a.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=480&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/86356/original/image-20150625-13002-1n1nb2a.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=480&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/86356/original/image-20150625-13002-1n1nb2a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=603&fit=crop&dpr=1 754w, https://images.theconversation.com/files/86356/original/image-20150625-13002-1n1nb2a.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=603&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/86356/original/image-20150625-13002-1n1nb2a.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=603&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">Might be hard to believe but parrots have a lot going on upstairs.</span>
<span class="attribution"><a class="source" href="http://www.eurekalert.org/multimedia/pub/94157.php">Courtesy of Jonathan E. Lee, Duke University</a></span>
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<p>Only parrots, humans and certain types of songbird can mimic other species. The fact that species as different as birds and humans share this behaviour is a clear example of “<a href="http://www.pbs.org/wgbh/evolution/library/01/4/l_014_01.html">convergent evolution</a>,” in which two species independently evolve structures supporting similar behaviours. </p>
<p>Imitation requires significant brain power and complex, specialised processes. For example, acoustic information must be represented, its organisation decoded and finally the sound reproduced. The complex specialisation of the core, shell and motor systems in parrots support these processes for imitation, enabling these species to couple auditory information from the environment with the finely grained behaviours necessary to produce them. There is currently no evidence suggesting that parrots have any special kind of articulators for producing spoken language. Rather, their brains seem to be doing the extra work.</p>
<h2>Let’s dance</h2>
<p>Interestingly, the authors also note that humans and parrots belong to another select set of animals – those that synchronise body movements to the rhythms of beats while listening to music. That is, unlike almost every other animal in the world, parrots and humans spontaneously dance (strangely enough, that group also includes elephants which have also demonstrated an ability to <a href="http://www.independent.co.uk/news/world/europe/elephants-sway-their-trunks-and-dance-to-classical-music--video-10322836.html">move along with music</a>). </p>
<p>In parrots, such dancing is associated with the non-vocal motor regions surrounding the shell – which supports the possibility of a general capacity for learning regularities in the sounds they hear and coupling them with behaviour.</p>
<p>The study is a big step forward in our effort to understand what makes parrots so different from other birds. Indeed, the researchers themselves say they were surprised that the brain structures they discovered had gone unrecognised for so long.</p><img src="https://counter.theconversation.com/content/43809/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Larry Taylor does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Scientists have identified the brain region that makes it possible for parrots to speak.Larry Taylor, Senior lecturer, Department of Psychology, Northumbria University, NewcastleLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/330072014-11-21T10:28:59Z2014-11-21T10:28:59ZThe unknown crocodiles<figure><img src="https://images.theconversation.com/files/64596/original/j4g8v3s4-1415983268.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Crocodiles keep their own secrets.</span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/tambako/908814138/">Tambako</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span></figcaption></figure><p>Just a few years ago, crocodilians – crocodiles, alligators and their less-known relatives – were mostly thought of as slow, lazy, and outright stupid animals. You may have thought something like that yourself the last time you were in a zoo and saw them lying still for hours, making people wonder if they were alive or made of plastic.</p>
<p>But people who worked with crocodilians – zoologists, breeders, animal trainers, tribal hunters – knew that these animals were capable of amazing things. And recently this knowledge has finally found support in the form of scientific publications.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/64605/original/bbnh6vxy-1415984389.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/64605/original/bbnh6vxy-1415984389.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/64605/original/bbnh6vxy-1415984389.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=380&fit=crop&dpr=1 600w, https://images.theconversation.com/files/64605/original/bbnh6vxy-1415984389.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=380&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/64605/original/bbnh6vxy-1415984389.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=380&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/64605/original/bbnh6vxy-1415984389.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=477&fit=crop&dpr=1 754w, https://images.theconversation.com/files/64605/original/bbnh6vxy-1415984389.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=477&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/64605/original/bbnh6vxy-1415984389.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=477&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Mugger crocodile using sticks to lure egrets.</span>
<span class="attribution"><span class="source">Vladimir Dinets</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Now we know that crocodilians have a weird <a href="http://www.asihcopeiaonline.org/doi/abs/10.1643/CE-12-125">communication system</a> composed of chemical signals, various calls, infrasound vibrations too low for us to hear, and body language. They can take care of their babies for more than a year, <a href="http://onlinelibrary.wiley.com/doi/10.1111/eth.12047/abstract;jsessionid=97321A8A418CD4F3CD71713374AABA60.f02t04?deniedAccessCustomisedMessage=&userIsAuthenticated=false">feeding them</a>, protecting them, even putting them together in <a href="http://onlinelibrary.wiley.com/doi/10.1111/eth.12047/abstract;jsessionid=97321A8A418CD4F3CD71713374AABA60.f02t04?deniedAccessCustomisedMessage=&userIsAuthenticated=false">crèches</a> – like daycare centers protected in turn by many parents. They can <a href="http://onlinelibrary.wiley.com/doi/10.1111/jzo.12052/abstract?deniedAccessCustomisedMessage=&userIsAuthenticated=false">disperse seeds</a> of rainforest trees. They can bond with <a href="http://en.wikipedia.org/wiki/Pocho_(crocodile)">certain people</a> and play with them. They can <a href="http://www.tandfonline.com/doi/full/10.1080/03949370.2013.858276#.VEN2dfldWSo">use little sticks</a> to lure egrets looking for nesting material. And they can <a href="http://www.tandfonline.com/doi/full/10.1080/03949370.2014.915432#.VEN2jPldWSo">hunt in teams</a>, each animal playing the role best suited for its size and agility; for example, large adult alligators can drive fish into shallows where small, agile youngsters lie in ambush.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/64603/original/9fbgwp5n-1415984167.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/64603/original/9fbgwp5n-1415984167.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/64603/original/9fbgwp5n-1415984167.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=255&fit=crop&dpr=1 600w, https://images.theconversation.com/files/64603/original/9fbgwp5n-1415984167.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=255&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/64603/original/9fbgwp5n-1415984167.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=255&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/64603/original/9fbgwp5n-1415984167.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=320&fit=crop&dpr=1 754w, https://images.theconversation.com/files/64603/original/9fbgwp5n-1415984167.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=320&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/64603/original/9fbgwp5n-1415984167.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=320&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Mugger crocodiles swimming in a circle to drive fish into a bait ball. One cuts across the circle to snatch fish.</span>
<span class="attribution"><span class="source">Vladimir Dinets</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>How they’ve maintained their mystique</h2>
<p>Why are these amazing facts only coming to light now? There are many reasons.</p>
<p>First, scientists <a href="http://www.nature.com/nature/journal/v423/n6940/full/423575a.html">don’t study natural history</a> as much as they used to. To get your research <a href="http://www.latimes.com/opinion/op-ed/la-oe-williams-wildlife-coburn-wastebook-20141107-story.html">financed</a> nowadays, it seems you need to be testing a fancy theory, or using a new technology, or contributing to some major cause such as finding cure for cancer, stopping global warming, or slowing down the ongoing mass extinction. You don’t get paid for just <a href="http://dx.doi.org/10.1093/biosci/biu032">watching animals</a>, no matter how cool the stuff is that you’re discovering. </p>
<p>Of course, this is a fundamentally wrong approach; it is impeding not just the science, but also our ability to fix major problems such as the mass extinction, because we no longer have the basic data on which our fancy theories should be based.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/64598/original/vp2vn8yf-1415983633.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/64598/original/vp2vn8yf-1415983633.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/64598/original/vp2vn8yf-1415983633.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/64598/original/vp2vn8yf-1415983633.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/64598/original/vp2vn8yf-1415983633.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/64598/original/vp2vn8yf-1415983633.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/64598/original/vp2vn8yf-1415983633.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/64598/original/vp2vn8yf-1415983633.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">American aligators dancing.</span>
<span class="attribution"><span class="source">Vladimir Dinets</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Second, crocodilian behavior is extremely difficult to see, especially in the wild. These are nocturnal animals living in swamps and muddy rivers, mostly in the tropics. Few people dare work there at night, and even fewer know how to observe nocturnal animals without disturbing them. These things aren’t taught in most universities. You can do your research in a zoo, but it’s not the same because many forms of behavior can only be seen in wild animals.</p>
<p>Third, time doesn’t flow for crocodilians like it does for us mammals. We are warm-blooded, so <a href="http://www.annualreviews.org/doi/abs/10.1146/annurev.nutr.19.1.247">we need a lot of energy</a> to keep our body temperature constant, and that makes us constantly hungry and active. Compared to us, crocodilians are the Taoist sages of the animal world. They lie back, <a href="http://www.jstor.org/discover/10.2307/2460833?uid=3739560&uid=2&uid=4&uid=3739256&sid=21104365198141">conserve energy</a> and silently absorb information about their surroundings. Eventually the moment comes when they decide it’s time for action, and when they do, they can make Jurassic Park’s velociraptors look like plucked chickens.</p>
<p>But to see this action, you have to spend weeks, months, sometimes years feeding mosquitoes in the swamps. Some Nile crocodiles, for example, hunt only once a year, during the wildebeest migration. Few scientists can afford to commit to a project where you get data once a year, if at all. Even if you somehow manage to get a grant for this, you’ll run out of money long before having something to show for it.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/64600/original/5ymcdtd3-1415983997.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/64600/original/5ymcdtd3-1415983997.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/64600/original/5ymcdtd3-1415983997.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=398&fit=crop&dpr=1 600w, https://images.theconversation.com/files/64600/original/5ymcdtd3-1415983997.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=398&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/64600/original/5ymcdtd3-1415983997.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=398&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/64600/original/5ymcdtd3-1415983997.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/64600/original/5ymcdtd3-1415983997.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/64600/original/5ymcdtd3-1415983997.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=501&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">I may be elusive but there’s plenty to discover about me and my brethren….</span>
<span class="attribution"><a class="source" href="http://pixabay.com/en/crocodile-alligator-predator-389090/">Mika Mamy</a></span>
</figcaption>
</figure>
<h2>Embrace the challenge</h2>
<p>The only way you can do it is by thinking out of the box. I write <a href="http://www.amazon.com/Dragon-Songs-Adventure-Crocodiles-Alligators/dp/1611458935/ref=sr_1_1?ie=UTF8&qid=1413707841&sr=8-1&keywords=dragon+songs">books</a> and sell my photos to finance my research. I use Facebook to survey people who don’t usually publish their observations in scientific journals: hunters, tour guides, zoo directors, amateur naturalists. I’ve learned to be as comfortable in a tropical swamp at night as I am in my apartment on a winter evening with the fireplace on and the coffee brewing.</p>
<p>Studying crocodilians is no longer a challenge for me – it’s pure fun. And the best part of it is that there’s still a lot to be discovered and understood. We’ve just scratched the surface.</p><img src="https://counter.theconversation.com/content/33007/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Vladimir Dinets does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Slow, lazy, stupid? It’s time to update your impression of the crocodilians. These animals are up to amazing things that we’re only beginning to observe and recognize.Vladimir Dinets, Research Assistant Professor of Psychology, University of TennesseeLicensed as Creative Commons – attribution, no derivatives.