tag:theconversation.com,2011:/us/topics/swarm-11932/articlesSwarm – The Conversation2023-08-02T17:13:54Ztag:theconversation.com,2011:article/2091802023-08-02T17:13:54Z2023-08-02T17:13:54ZHow swarming animals can help humans and AI make better decisions<figure><img src="https://images.theconversation.com/files/535929/original/file-20230705-23-hte9mu.jpeg?ixlib=rb-1.1.0&rect=0%2C0%2C6381%2C3444&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Starling murmurations form as daylight fades over their roosting sites. </span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/beautiful-large-flock-starlings-birds-fly-1930366580">Shutterstock / Albert Beukhof</a></span></figcaption></figure><p>The word swarm often carries negative connotations – think biblical plagues of locusts or high streets full of last-minute shoppers during the Christmas rush. However, swarming is essential for the survival of many animal collectives. And now research into swarming has the potential to change things for humans too.</p>
<p>Bees swarm to make their <a href="https://academic.oup.com/aesa/article/97/1/111/11469">search for new colonies</a> more effective. Flocks of starlings use <a href="https://link.springer.com/article/10.1007/s00265-018-2609-0">dazzling murmurations to evade and confuse predators</a>. These are just two examples from nature but swarming can be seen in almost every corner of the animal kingdom. </p>
<p>Research from mathematicians, biologists and social scientists is helping us understand swarming and harness its power. It’s already being used for <a href="https://ieeexplore.ieee.org/abstract/document/4424900">crowd control</a>, <a href="https://ieeexplore.ieee.org/abstract/document/5366981">traffic management</a> and to understand the <a href="https://ts2.space/en/swarm-intelligence-for-public-health-and-epidemiology/">spread of infectious diseases</a>. More recently, it’s starting to shape how we use data for healthcare, operate drones in military conflicts and has been used to beat near-insurmountable betting odds in sporting events.</p>
<p>A swarm is a system that is greater than the sum of its parts. Just as many neurons form a brain capable of thought, memory and emotion, groups of animals can act in unison to form a “super brain”, displaying highly complex behaviour not seen in individual animals. </p>
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<p>Artificial life expert Craig Reynolds revolutionised the study of swarming in 1986 with the publication of the <a href="https://dl.acm.org/doi/10.1145/37401.37406">Boids model</a> computer simulation. The Boids model breaks down swarming into a simple set of rules. </p>
<p>The Boids (bird-oids) in the simulation, like avatars or characters in a video game, are instructed to move in the same direction as their neighbours, move towards the average position of their neighbours, and avoid collisions with other boids. </p>
<p>Boids simulations are strikingly accurate when compared with real swarms. </p>
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<p>The Boids model suggests that swarming does not need leaders to coordinate behaviour – like pedestrians in a town centre rather than a guided museum tour. The complex behaviour we see in swarms arises from interactions between individuals following the same simple rules in parallel. In the language of physics, this phenomenon is known as <a href="https://www.sciencedirect.com/science/article/pii/S1476945X07000049?casa_token=6Lr13Hi0yzUAAAAA:eN6wloN9IBvWw5zl_iqVp1lFgyiKGa1P17Uk9QYkVLj6f0-DsFBQ1iFB0MT_YYKSNSi7S2mr">emergence</a>. </p>
<h2>The hive mind</h2>
<p>In 2016, US technology company <a href="https://unanimous.ai/">Unanimous AI</a> used the power of swarm intelligence to <a href="https://unanimous.ai/unu-superfecta-11k/">win the Kentucky Derby “superfecta” bet</a>, successfully predicting the first, second, third and fourth-placed riders in the famous US horse race. </p>
<p><a href="https://www.sbnation.com/2016/5/5/11594904/2016-kentucky-derby-picks-predictions-nyquist-mor-spirit">Industry experts</a> and <a href="https://hothardware.com/news/bing-predicts-kentucky-derby-winner-social-algorithms">conventional machine learning algorithms</a> made swathes of incorrect predictions. However, amateur racing enthusiasts recruited by Unanimous AI pooled their knowledge to beat the <a href="https://bleacherreport.com/articles/2638613-kentucky-derby-results-2016-winner-payouts-highlights-and-order-of-finish">541/1 odds</a>. </p>
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<span class="caption">Hopeful punters bet millions of dollars on the Kentucky Derby each year.</span>
<span class="attribution"><span class="source">Shutterstock / Cheryl Ann Quigley</span></span>
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<p>The volunteers’ success lay in the way in which their predictions were generated. Instead of voting on riders and aggregating their choices, the volunteers used <a href="https://unanimous.ai/swarm/">Unanimous AI’s swarm intelligence platform</a> to participate in a real-time digital tug of war, inspired by swarms of birds and bees.</p>
<p>All volunteers simultaneously pulled a dial towards their respective choices. This allowed people to change their preferences in response to the actions of others (for example, a person may have switched to pulling towards their second choice, B, rather than their first choice, C, if they saw A and B were the clear favourites). </p>
<p>Responding to one another in real time allowed Unanimous AI’s volunteers to collectively outperform <a href="https://www.sbnation.com/2016/5/5/11594904/2016-kentucky-derby-picks-predictions-nyquist-mor-spirit">highly-informed individuals</a>. </p>
<p>What’s more, had the most frequent individual picks of the volunteers determined the ordering, only the <a href="https://www.npr.org/sections/thetwo-way/2016/05/07/477171967/nyquist-wins-the-2016-kentucky-derby#:%7E:text=Carr%2FGetty%20Images-,Nyquist%2C%20ridden%20by%20Mario%20Gutierrez%2C%20crosses%20the%20finish%20line%20during,Churchill%20Downs%20on%20May%207.&text=Nearly%20one%20year%20since%20American,his%20own%20at%20Churchill%20Downs.">2016 winner</a> and <a href="https://www.sbnation.com/2016/5/7/11616138/2016-kentucky-derby-odds-post-nyquist-my-man-sam-exaggerator-bet-how">bookies’ favourite</a>, <a href="https://www.racingpost.com/profile/horse/896792/nyquist">Nyquist</a>, would have been placed correctly. </p>
<h2>Health concerns</h2>
<p>Similar swarming technologies are also of increasing interest in the <a href="https://www.nature.com/articles/s41586-021-03583-3">healthcare</a> sector, where <a href="https://www.frontiersin.org/articles/10.3389/fsoc.2022.1038854/full">talk of an AI revolution</a> is prompting <a href="https://digitalcommons.law.scu.edu/chtlj/vol36/iss4/2/">increasing concerns around patient privacy</a>. </p>
<p>As the reliance on <a href="https://link.springer.com/content/pdf/10.1007/s11518-019-5437-5.pdf">data-driven techniques in healthcare</a> increases, so too does the demand for extensive patient datasets. One way to meet these demands is to <a href="https://jamanetwork.com/journals/jama/fullarticle/2768851">pool information between institutions and in some cases, countries</a>. </p>
<p>However, the transfer of patient data is often subject to <a href="https://www.jmir.org/2017/2/e47/">stringent data protection regulations</a>. A solution to this problem is to use only in-house data, though this often comes at the expense of diagnostic accuracy. </p>
<p>An alternative lies in swarming. Researchers believe swarm intelligence can <a href="https://healthcare-in-europe.com/en/news/ai-with-swarm-intelligence-to-analyse-medical-data.html">preserve diagnostic accuracy</a> without the need for raw data exchange between institutions. </p>
<p><a href="https://www.nature.com/articles/s41586-021-03583-3">Preliminary studies</a> have shown decentralising data storage into a network of interacting nodes can give institutions the benefit of shared wisdom. This means there isn’t a central hub coordinating the flow of information, and institutions can’t access the private patient data of each other. </p>
<p>Centralised machine learning uses data uploaded to a shared hub where machine learning takes place using all available data. In decentralised systems, each institution separately stores its data in its own node. The machine learning happens locally at each node (using only in-house data), but the results of machine learning are shared between the network, to the benefit of all nodes. This process ensures that raw patient data is not exchanged between institutions, preserving patient privacy. </p>
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<span class="caption">Swarms of drones may soon populate the battlefield.</span>
<span class="attribution"><span class="source">Shutterstock / Andy Dean Photography</span></span>
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<h2>Swarms and warfare</h2>
<p>Drone technology is increasingly used in front-line combat, in recent times most notably by <a href="https://edition.cnn.com/2023/06/03/europe/ukraine-secretive-drone-program-russia-war-intl/index.html">Ukrainian forces</a> in the <a href="https://www.cfr.org/global-conflict-tracker/conflict/conflict-ukraine">ongoing Russia-Ukraine conflict</a>. However, as it stands, conventional drone technology requires <a href="https://www.airuniversity.af.edu/Portals/10/ASOR/Journals/Volume-1_Number-4/Lowther.pdf">one-to-one supervision</a>. </p>
<p><a href="https://www.army.mod.uk/news-and-events/news/2022/09/british-army-carries-out-successful-swarming-drone-capability/">Current defence research</a> aims to facilitate communication between drones, allowing one controller to operate swarms of drones. The development of such technology promises to vastly improve the <a href="https://www.military.africa/2023/06/drone-swarm-technology-an-overview/">scalability</a>, <a href="https://cdnsciencepub.com/doi/10.1139/juvs-2018-0009">reconnaissance</a> and <a href="https://www.eurasiantimes.com/edited-drone-swarms-controlling-drone-swarms-pentagon/">striking</a> capabilities of combat drones by allowing for continuous information relay within groups of drones. </p>
<p>As research delves deeper into swarming, we find a world where collective action creates complexity, adaptability, and efficiency. As technology evolves, the role of swarm intelligence is set to grow, intertwining our world with the fascinating dynamics of swarms.</p><img src="https://counter.theconversation.com/content/209180/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Samuel Johnson receives funding from Biotechnology and Biological Sciences Research Council (BBSRC). </span></em></p>Research into swarming in nature is transforming healthcare, gambling and the military.Samuel Johnson, DPhil Candidate in Mathematical Biology, University of OxfordLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1655972021-08-19T12:08:14Z2021-08-19T12:08:14ZLesson from a robot swarm: Change group behavior by talking one-on-one rather than getting on a soapbox<figure><img src="https://images.theconversation.com/files/416827/original/file-20210818-17-67o9ui.jpg?ixlib=rb-1.1.0&rect=51%2C0%2C5700%2C3771&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Persuading people one-on-one might be the best route to getting them to recognize better alternatives.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/couple-using-mobile-phone-while-walking-on-city-royalty-free-image/724230555">Maskot via Getty Images</a></span></figcaption></figure><p>You find a new restaurant with terrific food, but when you suggest meeting there in a group text to your friends, the choice to meet at the same old place carries the day.</p>
<p>Next time, you should consider persuading your friends one by one, rather than reaching out to the group as a whole. </p>
<p>Research conducted by <a href="https://bet-lab.group.shef.ac.uk">my colleagues</a> and <a href="https://www.giovannireina.com">me</a> using swarms of robots suggests that this less-is-more strategy of distributing information over time can increase the probability of getting a group to choose the best option. Our results could make it easier to develop microscopic robots that work inside the body, and could have implications for how information spreads on social media.</p>
<p>Our robot swarm study looked at how opinions spread in large populations. We found that a population of uninformed individuals <a href="https://doi.org/10.1126/scirobotics.abf1416">can cling to outdated beliefs</a> and fail to adopt better available alternatives when information about the new options spreads to everyone all at once. Instead, when individuals only share the information one by one, the population can better adapt to changes and reach an agreement in favor of the best option. </p>
<h2>Keeping it simple</h2>
<p>In <a href="https://doi.org/10.1126/scirobotics.abf1416">our study</a>, published in July 2021 in the journal Science Robotics, we set up a swarm of autonomous robots that make collective decisions on the best available alternatives and operate in an environment that changes over time. We found that less was more: robot swarms with reduced social connections – meaning the number of other robots they can communicate with – adapted more effectively than globally connected swarms. This runs counter to the common belief in network science that more connections <a href="https://doi.org/10.1103/PhysRevE.77.041121">always lead to more effective information exchange</a>. We show that there are situations when the opposite occurs.</p>
<p>Each <a href="https://www.k-team.com/mobile-robotics-products/kilobot">Kilobot</a> is less than an inch and a half (3.8 cm) in diameter and height, and communicates by infrared light. We programmed 50 of the robots with very simple behaviors: random movements to explore the environment and basic voting rules to exchange opinions. The robot swarm scans an unknown environment and collectively selects the best site; for example, the site best suited for building a structure. Each robot develops its own opinion from its scans of the environment and regularly checks the opinion of a single random neighbor. If a robot receives a conflicting opinion, it resets its own opinion by polling other robots. This allows the swarm to reach consensus without getting deadlocked.</p>
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<span class="caption">Experiments with swarms of robots have shown that sporadic social interactions can increase the spread of newly discovered information, compared to sharing the information with all members of a group at once.</span>
<span class="attribution"><span class="source">Andreagiovanni Reina</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
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<p>The simplicity of the individual behavior isn’t merely a matter of convenience in our study. It’s key to building <a href="https://doi.org/10.1126/scirobotics.abe4385">robot swarms of the future</a>. These include swarms with very small robots like <a href="https://doi.org/10.1126/scirobotics.aaz3867">microscopic robots that operate in the body</a>, robots with simple components like <a href="https://doi.org/10.1089/soro.2020.0011">biodegradable robots for cleaning the ocean</a>, and low-budget, single-use robots like those that could be <a href="https://doi.org/10.1038/s41586-019-1322-0">damaged or destroyed in disaster sites</a>. Robot swarms with minimal behaviors can also be a viable option for robots that <a href="https://doi.org/10.1126/scirobotics.aar7650">operate without human supervision</a> in otherwise inaccessible locations.</p>
<h2>Nature knows the rule</h2>
<p>To write the algorithms that control our robots, we built mathematical models that explain the spreading of opinions in populations of socially connected, uninformed individuals. This process is similar to collective decision-making in other settings, including animals and humans. </p>
<p>Specifically, our algorithm is inspired by the behavior of European honeybees <a href="https://doi.org/10.1126/science.1210361">when they collectively select the site to build their future nest</a>. Bees interact locally with one another and exchange voting messages by vibrations. The bee colony makes decisions without any central authority. </p>
<p>Similar collective decisions can be observed in schools of fish, who seem to know the less-is-more rule. In fact, recent research has shown that <a href="https://doi.org/10.1073/pnas.1905585116">schooling fish reduce their social network</a> — the number of fish they pay attention to — when they need to quickly absorb new information such as the source of a perceived threat.</p>
<h2>Caught by surprise</h2>
<p>Despite finding the less-is-more rule in nature, we did not expect to find it in our study of robot swarms. We were testing hundreds of robots running a <a href="https://doi.org/10.1103/PhysRevE.95.052411">model</a> based on observations of the collective behavior of honeybees selecting a nest site. This model allows the swarm to make decisions that take into account <a href="https://doi.org/10.1037/dec0000075">the value of the option</a> based on how much good news it’s receiving, whether it’s indicators of a good nest-building site or positive restaurant reviews. This means the swarm not only considers the relative quality of the alternatives but also their absolute quality, meaning whether any of the alternatives is good enough. </p>
<p>This corresponds to what organisms — including humans — typically do. For example, when picking where to eat, if all open restaurants serve meals below your standard for quality, you won’t care that one restaurant is 5% better than the others; you won’t eat out today. But if a couple of restaurants are very good, picking either of the two will be satisfying even if there is a 5% difference in quality between them. </p>
<p>When we implemented this in the robot swarm, we expected that the more the individuals were socially connected, the better the swarm would adapt to environmental changes. This is what is predicted and observed in most models of networked individuals. But we found the opposite: The less connected the group was, the better our robot swarm responded to a change. </p>
<p>We then built a mathematical model that described the system and explained the observed phenomenon. Environmental changes are discovered by a small group. In a globally connected network, the small group faces an almost impossible task in trying to overturn the established opinion of the majority, even if the environmental changes present a better alternative. Instead, when individuals interact sporadically and in small numbers, an opinionated minority can easily gain traction and change the opinion of the entire group in cases where the group opinion isn’t as strongly held as the minority’s opinion.</p>
<h2>Lessons for social media</h2>
<p>The <a href="https://doi.org/10.1126/scirobotics.abf1416">less-is-more effect</a> doesn’t hold up in all cases. We observed this phenomenon in networks where the individuals follow simple rules and changing the opinion of others is not instantaneous but requires some time. Humans, in certain contexts, have simple reactive behavior that doesn’t involve much thinking, and may therefore be subject to similar dynamics.</p>
<p>People are globally connected through social media, which influences the spread of opinions in large populations. Understanding how opinions change — and don’t — is crucial for <a href="https://www.pnas.org/content/118/27/e2025764118">facing the challenges of the digital age</a>.</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/us/newsletters/the-daily-3?utm_source=TCUS&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/165597/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Andreagiovanni Reina receives funding from the Belgian F.R.S.-FNRS, of which he is a Chargé de Recherches. He is affiliated with IRIDIA, the Institute for Interdisciplinary Studies on Artificial Intelligence, of the Université Libre de Bruxelles, in Belgium. </span></em></p>The collective behavior of robot swarms is a route to making small, simple, inexpensive robots – and offers insights into how people make group decisions and adapt to changes.Andreagiovanni Reina, FNRS Research Fellow, Université Libre de Bruxelles (ULB)Licensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1406252020-06-17T20:04:34Z2020-06-17T20:04:34ZHuge locust swarms are threatening food security, but drones could help stop them<p>In recent months, food security concerns have emerged for nations across Africa, Asia and the Middle East, as swarms of desert locusts <a href="https://www.theguardian.com/global-development/2020/mar/20/locust-crisis-poses-a-danger-to-millions-forecasters-warn">wreak havoc</a> on crops.</p>
<p>While the same level of damage isn’t currently being felt in Australia, the threat of infestations extends to us too. But drone technology is offering up solutions.</p>
<h2>Not just a Biblical threat</h2>
<p>In January, the United Nations Food and Agriculture Organisation (FAO) <a href="http://www.fao.org/news/story/en/item/1258877/icode/">warned</a> rising locust numbers in the Horn of Africa presented an “extremely alarming and unprecedented threat” to food security and livelihoods. </p>
<p>According to the FAO, a swarm of about 40 million desert locusts can eat the <a href="http://www.fao.org/ag/locusts/en/info/info/faq/index.html#:%7E:text=A%20Desert%20Locust%20adult%20can,day%20as%20about%2035%2C000%20people.">same amount of food</a> in one day as about 35,000 people. Swarms <a href="http://www.fao.org/ag/locusts/oldsite/LOCFAQ.htm#q1">can be</a> as large as several hundred square kilometres, with as many as 80 million adults per square kilometre.</p>
<p>Countries <a href="https://www.theguardian.com/global-development/2020/jun/08/rolling-emergency-of-locust-swarms-decimating-africa-asia-and-middle-east#_=_">impacted</a> by infestations this year include Ethiopia, Kenya, Uganda, Somalia, India, Pakistan, Iran, Yemen, Oman and Saudi Arabia.</p>
<p>A review of records by the <a href="https://www.agriculture.gov.au/pests-diseases-weeds/locusts">Australian Plague Locust Commission</a> has reported eight large outbreaks in Australia since 1930. The FAO has <a href="https://www.aap.com.au/un-to-set-drones-on-east-africa-locusts/">encouraged</a> the use of drones to provide early warning systems that may help prevent locust outbreaks. </p>
<h2>Control with technology</h2>
<p>In nature, locusts are controlled by birds, spiders, parasitic flies and wasps – but these aren’t effective when numbers explode. </p>
<p>In Australia, locusts are generally controlled by aerial spraying of pesticides from light aircraft. One solution may be to destroy eggs by ploughing in crops or pastures, but there’s <a href="http://agriculture.vic.gov.au/agriculture/pests-diseases-and-weeds/pest-insects-and-mites/plague-locusts/fact-sheet-forestry-and-plantations">no conclusive data</a> on how effective this is.</p>
<p>Drones are now providing an innovative alternative to the more expensive use of light aircrafts. These aerial vehicles can be used to remotely sense areas, carry out pest surveillance and monitor crop growth.</p>
<p>They also allow for targeted pesticide application through atomiser sprayers that deliver a fine, even spray from liquid.</p>
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Read more:
<a href="https://theconversation.com/how-many-locusts-does-it-take-to-start-a-biblical-plague-just-three-49548">How many locusts does it take to start a biblical plague? Just three</a>
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<p>Each state and territory of Australia has been affected by plague locusts at some point in the past, with outbreaks having occurred in Queensland, New South Wales, Victoria, South Australia and Western Australia. The <a href="https://www.agriculture.gov.au/sites/default/files/documents/locust-Bulletin-April-2020.pdf">latest April</a> bulletin shows limited outbreaks in New South Wales. </p>
<p>There is a growing body of <a href="https://www.researchgate.net/publication/337826660_Drones_Innovative_Technology_for_Use_in_Precision_Pest_Management">research</a> on the use of drones for pest monitoring and management, with several Australian agricultural consultancy companies <a href="https://foresttech.events/how-drones-are-being-used-in-australia-to-make-farming-more-efficient/">offering</a> drone services for crop and soil monitoring. State and federal agricultural agencies also use drones for crop, disease and pest monitoring. </p>
<p>Understanding the movement of locusts helps determine the best way to control crop damage. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/342373/original/file-20200617-94060-1rwu0zx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/342373/original/file-20200617-94060-1rwu0zx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/342373/original/file-20200617-94060-1rwu0zx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/342373/original/file-20200617-94060-1rwu0zx.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/342373/original/file-20200617-94060-1rwu0zx.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/342373/original/file-20200617-94060-1rwu0zx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/342373/original/file-20200617-94060-1rwu0zx.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/342373/original/file-20200617-94060-1rwu0zx.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">Agriculture drones can be used to spray fertiliser and pesticide on crops.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
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<p>Last month marked the first time <a href="https://timesofindia.indiatimes.com/india/in-a-first-drone-used-to-clear-locust-swarms-in-chomu/articleshow/76053417.cms">drones were used</a> to clear swarms in Rajasthan, India. Spraying insecticides dispersed the insects into different areas. </p>
<p>Drones can also be used in the aftermath of infestations. For instance, recent outbreaks in Kenya have seen the use of drones for post-disaster mapping. <a href="https://reliefweb.int/report/kenya/east-africa-race-outsmart-locusts-drones-and-data">These maps</a>, along with satellite information, can provide more accurate assessments of the extent of crop loss.</p>
<p>On-ground <a href="https://www.techbriefs.com/component/content/article/tb/features/articles/33212">internet-connected sensors</a> with thermal and image processing capabilities could also potentially be used to monitor the spread of infestations. These could provide additional real-time monitoring to support satellite imagery.</p>
<h2>Some bugs remain</h2>
<p>There are limitations when it comes to using drones to tackle locust problems.</p>
<p>Drones don’t perform well in areas that are densely packed with locusts, due to damage to propellers. And while the technical specifications of drones have made rapid improvements over the past few years, they still only provide a limited load of insecticide for spraying.</p>
<p>The duration of flying time for drones is also usually <a href="https://3dinsider.com/long-range-drones/">less than an hour</a>. Flying drones requires a degree of expertise, and any commercial drone flying requires certification from the <a href="https://www.casa.gov.au/">Civil Aviation Safety Authority</a>.</p>
<h2>Small creature, big bite</h2>
<p>Locusts belong to the same order of insects as grasshoppers, katydids and crickets. Locusts are grasshoppers that develop “gregarious” behaviours and become more voracious as a result. </p>
<p>Grasshoppers can <a href="https://www.cam.ac.uk/research/news/a-brain-chemical-changes-locusts-from-harmless-grasshoppers-to-swarming-pests">become gregarious</a> and start to swarm due to an increase in chemical serotonin in their nervous system. This results in them going from individual walking grasshoppers to flying locusts. There are no clear differences between locusts and grasshoppers <a href="https://www.worldatlas.com/articles/what-is-the-difference-between-grasshoppers-and-locusts.html">other than behaviour</a>. </p>
<p>In Australia there are three main pest locust species: the Australian plague locust (<em>Chortoicetes terminifera</em>), the spur-throated locust (<em>Austracris guttulosa</em>) and the migratory locust (<em>Locusta migratoria</em>). Controlling these <a href="https://www.agric.wa.gov.au/pest-insects/australian-plague-locust-frequently-asked-questions">pests</a> is difficult when they travel in swarms. </p>
<p>Locust swarms can decimate swathes of crop in their way, <a href="http://agriculture.vic.gov.au/agriculture/pests-diseases-and-weeds/pest-insects-and-mites/plague-locusts/fact-sheet-vegetable-and-herbs#:%7E:text=The%20Australian%20plague%20locust%20prefers,%2C%20pasture%2C%20grapevines%20and%20trees.">consuming everything</a> from leaves and grains, to pastures and even trees.</p>
<p>With ongoing locust infestations, a rise in extreme weather events, and now COVID-19, the struggles faced by farmers the world over are compounded. Improving current technologies and finding new ways to innovate may help ease this burden in the coming years.</p>
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<em>
<strong>
Read more:
<a href="https://theconversation.com/swarming-locusts-people-used-to-eat-them-but-shouldnt-anymore-135058">Swarming locusts: people used to eat them, but shouldn't anymore</a>
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<img src="https://counter.theconversation.com/content/140625/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Leisa Armstrong 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>A swarm of roughly 40 million desert locusts can eat the same amount of food in one day as about 35,000 people.Leisa Armstrong, Senior Lecturer in Computer Science, Edith Cowan UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1251942020-01-22T13:37:19Z2020-01-22T13:37:19ZWhat a bundle of buzzing bees can teach engineers about robotic materials<figure><img src="https://images.theconversation.com/files/308138/original/file-20191220-11904-19nzsit.jpg?ixlib=rb-1.1.0&rect=613%2C0%2C3987%2C3055&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Individuals working together as one.</span> <span class="attribution"><span class="source">Orit Peleg and Jacob Peters</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span></figcaption></figure><p>Gathered inside a small shed in the midst of a peaceful meadow, my colleagues and I are about to flip the switch to start a seemingly mundane procedure: using a motor to shake a wooden board. But underneath this board, we have a swarm of roughly 10,000 honeybees, clinging to each other in a single magnificent pulsing cone.</p>
<p>As we share one last look of excited concern, the swarm, literally a chunk of living material, starts to move right and left, jiggling like jelly. </p>
<p>Who in their right minds would shake a honeybee swarm? My colleagues and I are studying swarms to deepen our understanding of these essential pollinators, and also to see how we can leverage that understanding in the world of robotics materials.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/307042/original/file-20191216-123998-19vuyqy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/307042/original/file-20191216-123998-19vuyqy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/307042/original/file-20191216-123998-19vuyqy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=299&fit=crop&dpr=1 600w, https://images.theconversation.com/files/307042/original/file-20191216-123998-19vuyqy.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=299&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/307042/original/file-20191216-123998-19vuyqy.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=299&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/307042/original/file-20191216-123998-19vuyqy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=376&fit=crop&dpr=1 754w, https://images.theconversation.com/files/307042/original/file-20191216-123998-19vuyqy.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=376&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/307042/original/file-20191216-123998-19vuyqy.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=376&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">Honeybee swarms adapt to different branch shapes.</span>
<span class="attribution"><span class="source">Orit Peleg and Jacob Peters</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
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</figure>
<h2>Many bees create one swarm</h2>
<p>The swarms in our study occur as part of the <a href="https://www.scientificamerican.com/article/how-honeybees-find-a-home/">reproductive cycle of European honeybee colonies</a>. When the number of bees exceeds available resources, usually in the spring or summer, a colony divides into two groups. One group, and a queen, fly away in search of a new permanent location while the rest of the bees remain behind.</p>
<p>During that effort, the relocating bees temporarily form a highly adaptable swarm that can hang from tree branches, <a href="https://apnews.com/3565459f20454cf399310eccd3bfbadf/NYPD-bee-squad-ready-for-sting-operations-on-urban-swarms">roofs, fences or cars</a>. While suspended, they have no nest to protect them from the elements. Huddling together allows them <a href="https://doi.org/10.1098/rsif.2013.1033">to minimize heat loss to the colder outside environment</a>. They also need to adapt in real time to temperature variations, rain and wind – all of which could shatter the fragile protection they share as one unit.</p>
<p>The swarm is orders of magnitude larger than the size of an individual bee. A bee could potentially coordinate its activity with neighboring bees right next to it, but it certainly couldn’t coordinate directly with any bees at the far edge of the swarm.</p>
<p>So how do they manage to maintain mechanical stability in the face of something like strong wind – a test that requires near simultaneous coordination throughout the entire swarm?</p>
<p>My colleagues <a href="https://scholar.google.com/citations?user=YYtLjJoAAAAJ&hl=en&oi=sra">Jacob Peters</a>, <a href="https://scholar.google.com/citations?user=Xt6THm8AAAAJ&hl=en&oi=ao">Mary Salcedo</a>, <a href="https://scholar.google.com/citations?user=iiyj5MsAAAAJ&hl=en&oi=sra">L. Mahadevan</a> and I devised a series of experiments to address that question — which brings us back to intentionally shaking the swarm.</p>
<h2>Individual actions, whole swarm response</h2>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/307045/original/file-20191216-124027-1k6kspl.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/307045/original/file-20191216-124027-1k6kspl.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/307045/original/file-20191216-124027-1k6kspl.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=717&fit=crop&dpr=1 600w, https://images.theconversation.com/files/307045/original/file-20191216-124027-1k6kspl.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=717&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/307045/original/file-20191216-124027-1k6kspl.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=717&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/307045/original/file-20191216-124027-1k6kspl.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=901&fit=crop&dpr=1 754w, https://images.theconversation.com/files/307045/original/file-20191216-124027-1k6kspl.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=901&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/307045/original/file-20191216-124027-1k6kspl.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=901&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Examining the experimental setup, with the pyramidal swarm hanging from the bottom of the board.</span>
<span class="attribution"><span class="source">Orit Peleg and Jake Peters</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
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<p>When we shook the swarm along its horizontal axis, the bees adjusted the shape of their swarm and within minutes became a wider, more stable cone. However, when the motion was vertical, the shape remained constant until a critical force was reached that caused the swarm to break apart.</p>
<p>Why did the bees respond to horizontal shaking, but not to vertical shaking? It’s all about how the <a href="https://doi.org/10.1038/s41567-018-0262-1">bonds bees create by “holding hands”</a> get stretched.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/310361/original/file-20200115-134772-sfa6ua.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/310361/original/file-20200115-134772-sfa6ua.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/310361/original/file-20200115-134772-sfa6ua.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/310361/original/file-20200115-134772-sfa6ua.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/310361/original/file-20200115-134772-sfa6ua.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/310361/original/file-20200115-134772-sfa6ua.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/310361/original/file-20200115-134772-sfa6ua.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/310361/original/file-20200115-134772-sfa6ua.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">Honeybees are essentially holding hands to create the dense swarm structure. How much the bonds between two bees stretch is important information that influences their actions for the good of the swarm.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/trust-teamwork-bees-linking-two-bee-262155599">Viesinsh/Shutterstock.com</a></span>
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<p>It turns out vertical shaking doesn’t disrupt these pair bonds as much as horizontal shaking does. Using a computational model, we showed that bonds between bees located closer to where the swarm attaches to the board stretch more than bonds between bees at the far tip of the swarm. Bees could sense these different amounts of stretching, and use them as a directional signal to move upwards and make the swarm spread. </p>
<p>In other words, bees move from locations where bonds stretch less, to locations where they stretch more. This behavioral response improves the collective stability of the swarm as a whole at the expense of increasing the average burden experienced by the individual bee. The result is a kind of “mechanical altruism”, as the one bee endures strain for the benefit of the swarm’s greater good.</p>
<h2>Engineering lessons, taught by bees</h2>
<p><a href="https://scholar.google.com/citations?user=xH5Ryy4AAAAJ&hl=en&oi=ao">As a broadly trained physicist studying animal behavior</a>, I am fascinated by this kind of evolved solution in nature. It’s amazing that honeybees can create multi-functional materials – made of their many individual bodies – that can shape shift without a global conductor telling them all what to do. No one is in charge, but together they keep the swarm intact. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/jswSJznyvDI?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Bee swarms exhibit emergent intelligence, behaving as one unit.</span></figcaption>
</figure>
<p>What if engineers could take those solutions and lessons from nature and apply them to buildings? Instead of a bundle of buzzing bees, could you imagine a bundle of buzzing robots that cling on each other to create adaptive structures in real time? I can <a href="https://www.arch2o.com/hypercell-thesis-aadrl/">envision shelters</a> that deploy rapidly in the face of natural disasters like hurricanes, or construction materials that can sense an earthquake’s vibrations and respond in the same way that these swarms react to a branch in wind.</p>
<p>Essentially, these bees create an autonomous material that – embedded within itself – has multiple abilities. The swarm can sense information from the nearby environment, based on how much the pair bonds are stretching. It can compute, in the sense that it figures out which regions have more bond stretching. And it can actuate, meaning move in the direction toward more stretching.</p>
<p>These properties are some of the longstanding aspirations in the fields of <a href="https://doi.org/10.1126/science.1261689">multi-functional materials and robotics materials</a>. The idea is to combine affordable robots that each have a minimal amount of mechanical components and sensors, like the <a href="http://news.mit.edu/2019/self-transforming-robot-blocks-jump-spin-flip-identify-each-other-1030">M-blocks</a>. Together they can sense their local environment, interact with neighboring robots and make their own decisions on where to move next. As Hiro, the young roboticist in the Disney movie “<a href="https://youtu.be/ep2-W1X65KI?t=55">Big Hero 6</a>” says, “The applications to this tech are limitless.”</p>
<p>For the moment, <a href="https://www.thisiscolossal.com/2019/12/spatial-bodies-aujik/?fbclid=IwAR1QWvNE_NiEiVsZR6pWZRFGoknPjsex0Ji05L-OFTDXmv8WlXDtlkiy7d8">this is still science fiction</a>. But the more researchers know about the honeybees’ natural solutions, the closer we get to making that dream come true.</p>
<p>[ <em>Get the best of The Conversation, every weekend.</em> <a href="https://theconversation.com/us/newsletters/weekly-highlights-61?utm_source=TCUS&utm_medium=inline-link&utm_campaign=newsletter-text&utm_content=weeklybest">Sign up for our weekly newsletter</a>. ]</p><img src="https://counter.theconversation.com/content/125194/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Orit Peleg receives funding from the Human Frontiers Science Program. </span></em></p>A swarm of honeybees can provide valuable lessons about how a group of many individuals can work together to accomplish a task, even with no one in charge. Roboticists are taking notes.Orit Peleg, Assistant Professor of Computer Science, University of Colorado BoulderLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/985862018-06-20T10:16:21Z2018-06-20T10:16:21ZIn praise of the midges pestering footballers in the World Cup<p>England’s opening match in World Cup 2018 was a dramatic clash between Gareth Southgate’s Young Lions and <a href="https://www.bbc.co.uk/sport/football/44519710">several million gnats</a>, not to mention Tunisia’s wrestling footballers. England pulled a win out of the bag <a href="https://www.bbc.co.uk/sport/football/44533213">at the last minute</a> – but only after a gruelling fight with some determined insects. Those plucky gnats also had to fight off the insecticide treatments of nearby swamps and insect repellent sprays deployed by the team and the media. </p>
<p>I suppose this could open up new possibilities for product endorsement – in addition to the usual shampoo and shaving adverts – if you need to <a href="https://www.youtube.com/watch?v=GmLNoHMnvEA">shave your chest</a> and remove any unsightly insect life that might have got stuck to you during a game.</p>
<p>But, despite the bad press, these swarms of midges are a very heartening sight. The last year has seen a series of reports spotlighting the grim decline of insect abundance in Europe (notably <a href="https://www.researchgate.net/profile/Theo_Zeegers/publication/325206013_Analysis_of_insect_monitoring_data_from_De_Kaaistoep_and_Drenthe/links/5afdcf30aca272b5d80f3ae0/Analysis-of-insect-monitoring-data-from-De-Kaaistoep-and-Drenthe.pdf">long-term data from Germany</a>) which has provoked headlines of ecological Armageddon and a fond nostalgia for the days of <a href="https://theconversation.com/the-moth-snowstorm-an-environmental-call-to-arms-as-powerful-as-silent-spring-67576">bug-filled countryside jaunts</a>. </p>
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<p>The trouble is that while bees and butterflies readily gain our sympathy, other vital groups that do much of the pollinating and other crucial work that helps keep the planet turning have a dodgier reputation. Of all the bugs, it is flies that may be the hardest to like. The ones that generally attract our attention sit around on poo, vomit on our food or bite us for blood. </p>
<p>Flies can take little solace from their place in high culture. Shakespeare points out their appetite for public casual sex (King Lear, Act 4), while the Old Testament threatens plagues on multiple occasion in Exodus, or the Book of Isiah where they are summoned from the furthest rivers (which at least shows an appreciation of the powers of gnat dispersal).</p>
<p>But we dismiss flying “pests” at our peril – and the Volgograd pitch invaders may be a particularly important group for our welfare – if we can work out what they are.</p>
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<p>The precise identification of the pesky Volgograd Diptera (fly) is uncertain: are they mosquitoes, midges or gnats? The general abundance and behaviour suggests midges – but midges come in many forms. In much of the northern temperate world the biting midges of the family Ceratopogondiae are notorious. The UK version – the Highland Midge – is credited with <a href="https://must-see-scotland.com/midges-in-scotland/">scaring away tourists</a> from Scotland. They are tiny but determined females in search of a blood meal. They get in ears, eyes and noses and make them a tickling mess. </p>
<p>However the Volgograd midges seem bigger, almost beautiful as they sparkled in the setting sun, much more like Chironomidae – so called non-biting midges. Lacking the bloodthirsty reputation of their biting cousins, it is easy to take the Chironomidae for granted – but they deserve our thanks. </p>
<h2>Fighting pollution</h2>
<p>In countries with sewage treatment works it is Chironomidae larvae that do much of the sewage processing, preventing the gross pollution of waterways. Sewage treatment commonly involves filtering out the larger debris we flush away, then dribbling the resulting liquid slowly through large gravel beds. In these gravel beds, billions of midge larvae feast on the organic soup, turning much of our waste in midge biomass. This is why sewage plants are often prized by bird watchers as the sheer quantity of flies that eventually emerge make a great food source, attracting all sorts of avian visitors.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/224001/original/file-20180620-137711-m0vthb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/224001/original/file-20180620-137711-m0vthb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=451&fit=crop&dpr=1 600w, https://images.theconversation.com/files/224001/original/file-20180620-137711-m0vthb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=451&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/224001/original/file-20180620-137711-m0vthb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=451&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/224001/original/file-20180620-137711-m0vthb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=567&fit=crop&dpr=1 754w, https://images.theconversation.com/files/224001/original/file-20180620-137711-m0vthb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=567&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/224001/original/file-20180620-137711-m0vthb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=567&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A non-biting Chironomidae on a pine needle.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/nonbiting-midget-chironomidae-on-pine-needle-285316016?src=nrw4rY3MY0hwClZjodK-_g-1-20">Shutterstock/HenrikLarsson</a></span>
</figcaption>
</figure>
<p>The midge’s larvae are tough. Some species hang on in severely degraded rivers, familiar as “blood worms” – vivid red because of haemoglobin in their bodies to glean the limited oxygen from the mud. Each midge may be tiny but hatching numbers are colossal. East African rift valley lakes may seem to smoke <a href="https://www.bbc.co.uk/programmes/p0065wmb">as rising clouds of Chironomidae</a> emerge. </p>
<p>The massive swarms can be harvested, squished into midge-balls and eaten by lakeside villagers. Midge swarms seem to show <a href="http://journals.plos.org/ploscompbiol/article?id=10.1371/journal.pcbi.1003697">remarkable collective manoeuvres</a>, individual midges adjusting velocity and direction response to their immediate neighbours, detecting shifts up to at least a centimetre away (although studies do not account for the impact of footballers waving their hands about).</p>
<p>Evening is prime time for swarms as males dance in the hope of attracting a mate, so the Volgograd kick-off was perfectly timed to attract midge trouble as millions of males, newly emerged and looking their best, hit the town. Let’s not be too down on midges. The 2-1 scoreline will encourage England fans. For those who appreciate flies, the dancing swarms will also gladden the heart.</p>
<hr>
<p><em>More evidence-based articles about football and the <a href="https://theconversation.com/uk/topics/world-cup-2018-11490?utm_source=TCUK&utm_medium=linkback&utm_campaign=TCUKengagement&utm_content=WorldCup2018">World Cup</a>:</em></p>
<ul>
<li><p><em><a href="https://theconversation.com/how-to-keep-footballers-fit-and-fuelled-for-a-world-cup-97803?utm_source=TCUK&utm_medium=linkback&utm_campaign=TCUKengagement&utm_content=WorldCup2018">How to keep footballers fit and fuelled for a World Cup</a></em></p></li>
<li><p><em><a href="https://theconversation.com/world-cup-all-the-ways-footballers-and-fans-can-be-hacked-97572?utm_source=TCUK&utm_medium=linkback&utm_campaign=TCUKengagement&utm_content=WorldCup2018">World Cup: All the ways footballers and fans can be hacked</a></em></p></li>
<li><p><em><a href="https://theconversation.com/world-cup-var-technology-is-transforming-the-beautiful-game-97907?utm_source=TCUK&utm_medium=linkback&utm_campaign=TCUKengagement&utm_content=WorldCup2018">World Cup VAR: technology is transforming the beautiful game</a></em></p></li>
</ul><img src="https://counter.theconversation.com/content/98586/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Mike Jeffries 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>Footballers came under attack from a swarm of flies on the Volgograd pitch. But there’s more to midges and gnats than meets the eye.Mike Jeffries, Associate Professor, Ecology, Northumbria University, NewcastleLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/807172017-07-11T23:34:43Z2017-07-11T23:34:43ZHow do fire ants form giant rafts to survive floods?<figure><img src="https://images.theconversation.com/files/177751/original/file-20170711-26274-kiqbpp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">How do they each know what to do?</span> <span class="attribution"><span class="source">Tim Nowack</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span></figcaption></figure><p>Drop a clump of 100,000 fire ants in a pond of water – or <a href="https://www.wired.com/story/why-those-floating-fire-ant-colonies-in-texas-are-such-bad-news">flood a huge area of Texas</a> that’s infested with fire ants and drive them out of their nests in large groups. In minutes the clump will flatten and spread into a circular pancake that can float for weeks without drowning the ants.</p>
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<p><div data-react-class="Tweet" data-react-props="{"tweetId":"651908417670545409"}"></div></p>
<p>Drop the same clump of ants near a plant on solid ground.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/177646/original/file-20170711-5963-1izzcxk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/177646/original/file-20170711-5963-1izzcxk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/177646/original/file-20170711-5963-1izzcxk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=645&fit=crop&dpr=1 600w, https://images.theconversation.com/files/177646/original/file-20170711-5963-1izzcxk.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=645&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/177646/original/file-20170711-5963-1izzcxk.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=645&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/177646/original/file-20170711-5963-1izzcxk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=811&fit=crop&dpr=1 754w, https://images.theconversation.com/files/177646/original/file-20170711-5963-1izzcxk.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=811&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/177646/original/file-20170711-5963-1izzcxk.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=811&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Hundreds of thousands of ants creating a tower together – but how?</span>
<span class="attribution"><span class="source">Candler Hobbs, Georgia Tech</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>They’ll climb atop each other to a form a solid mass around the plant stem in the shape of the Eiffel Tower – sometimes as high as 30 ants tall. The ant tower serves as a temporary encampment that repels raindrops.</p>
<p>How and why do the ants make these symmetrical but very different shapes? They <a href="https://www.youtube.com/watch?v=N8XsTTNOIVE">depend on touch and smell</a> – not sight – to perceive the world, so they can sense only what’s very close to them. Contrary to popular belief, the queen doesn’t issue orders to the colony; she <a href="http://articles.extension.org/pages/55044/life-in-a-fire-ant-family:-brood-eggs-larvae-and-pupae">spends her life laying eggs</a>. Each ant controls itself, based on information gathered from its immediate vicinity.</p>
<p>As both a systems engineer and biologist, I’m fascinated by the ant colony’s effectiveness in diverse tasks, such as foraging for food, floating on water, fighting other ants and building towers and underground nests – all accomplished by thousands of purblind creatures whose brains have less than <a href="https://en.wikipedia.org/wiki/List_of_animals_by_number_of_neurons">one ten-thousandth as many neurons as a human’s</a>.</p>
<p>In earlier research, my colleague <a href="https://theconversation.com/profiles/david-hu-204122">David Hu</a> and I investigated how these tiny creatures weave their bodies <a href="https://doi.org/10.1073/pnas.1016658108">into water-repellent lifesaving rafts</a> that float for weeks on flood waters. (This didn’t happen after Katrina flooded New Orleans in 2005 because the storm surge and levee collapses happened so fast the ants couldn’t escape their nests, and drowned. Harvey’s floods resulted from rain over a much longer period of time.)</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/UxjT99l0mqw?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">David Hu describes how fire ants form their escape rafts.</span></figcaption>
</figure>
<p>Now we wanted to understand how the same ants coordinate to assemble into a completely different <a href="https://doi.org/10.1098/rsos.170475">structure on land – a tower</a> made of as many as hundreds of thousands of living fire ants.</p>
<h2>How supportive are fire ants?</h2>
<p>Half the ants here in Georgia are fire ants, <em><a href="http://www.antwiki.org/wiki/Solenopsis_invicta">Solenopsis invicta</a></em>. To collect our lab subjects, we slowly pour water into an underground nest, forcing the ants to the surface. Then we capture them, take them to the lab, and keep them in bins. After some painful bites we learned to line the bins with baby powder to prevent their escape.</p>
<figure class="align-left zoomable">
<a href="https://images.theconversation.com/files/177702/original/file-20170711-28771-1lisks6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/177702/original/file-20170711-28771-1lisks6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/177702/original/file-20170711-28771-1lisks6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=661&fit=crop&dpr=1 600w, https://images.theconversation.com/files/177702/original/file-20170711-28771-1lisks6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=661&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/177702/original/file-20170711-28771-1lisks6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=661&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/177702/original/file-20170711-28771-1lisks6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=830&fit=crop&dpr=1 754w, https://images.theconversation.com/files/177702/original/file-20170711-28771-1lisks6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=830&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/177702/original/file-20170711-28771-1lisks6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=830&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Fire ants forming a tower around a narrow pole.</span>
<span class="attribution"><span class="source">Georgia Tech</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>To trigger their tower building, we put a clump of ants in a petri dish and simulated a plant stem with a small vertical pole in the center. The first thing we noticed about their tower was that it was always narrow at the top and wide at the bottom, like the bell of a trumpet. A pile of dead ants is conical. Why the bell shape? </p>
<p>Our first guess, that more ants were needed toward the bottom to support more weight, proved accurate. To be precise, we hypothesized that each ant is willing to support the weight of a certain number of other ants, but no more.</p>
<p>From this hypothesis we derived a mathematical formula that predicted the width of the tower as a function of height. After measuring towers made of different numbers of ants, we confirmed our model: ants were willing to support the weight of three of their brethren – but not more. So the number of ants needed in a layer had to be the same as in the next layer up (to support the weight of all the ants above the next layer), plus one-third the number in the next layer (to support the next layer). </p>
<p>Later, we learned that architect Gustave Eiffel <a href="http://www.ce.jhu.edu/perspectives/studies/Eiffel%20Tower%20Files/ET_Loads.htm">used the same principle of equal load-bearing</a> for his famous tower.</p>
<h2>Ring around the pole</h2>
<p>Next we asked how fire ants build the tower. Of course they’re not doing the math that would tell them how many ants need to go where to create this distinctive shape. And why does it take them 10 to 20 minutes rather than the mere one or two minutes needed to build a raft? This took us seven trial hypotheses over two frustrating years to answer.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/mx_jdT0gkTc?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Watch the ants build a tower in real time.</span></figcaption>
</figure>
<p>Although we think of a tower as made of horizontal layers, the ants don’t build the tower by completing the bottom layer and adding one complete layer at a time. They can’t “know” in advance how wide the bottom layer must be. There isn’t any way for them to count how many ants there are, much less to measure a layer’s width or calculate the necessary width.</p>
<p>Instead, ants scurrying about on the surface get attached and thereby thicken the tower at all layers. The top layer is always formed atop what had just previously been the top layer. Being the narrowest, it consists of a ring of ants around the pole, each gripping its two horizontally adjacent ants.</p>
<p>Our key observation was that if a ring does not completely encircle the pole, it doesn’t support other ants that are trying to build another ring on top of them. After measuring ant grip and adhesion strengths, we analyzed the physics of the ring and determined that a complete ring is 20 to 100 times more stable than an incomplete one. It looked like ring formation might be the bottleneck for tower growth.</p>
<p>This hypothesis gave us a testable prediction. A larger-diameter pole has more ring places to be filled, so its tower should grow more slowly. To get a quantitative prediction, we mathematically modeled the ant movements as being in random directions for a distance of about a centimeter – the same as in our model of ant movement for ant raft formation.</p>
<p>Then we filmed closeups of ants moving into places on the ring. Based on over 100 data points, we got strong confirmation of our model of ring-filling. When we ran tower-building experiments with a range of pole diameters, sure enough, the towers grew more slowly around larger-diameter poles, at rates that matched our predictions fairly well.</p>
<h2>Sinking in slow motion</h2>
<p>There was one big surprise to come. We thought that once the tower was complete, that was all there was. But in one of our experimental trials, we accidentally left the video camera running for an extra hour after the tower had been built.</p>
<p>Then-Ph.D.-student <a href="http://antlab.gatech.edu/antlab/About_Me.html">Nathan Mlot</a> was too good a scientist to just discard observational data. But he didn’t want to waste an hour watching nothing happen. So he watched the video at 10x normal speed – and what he saw was amazing.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/eXB-q8g4x9w?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Time-lapse video of an ant tower. Sulisay Phonekeo, Georgia Tech.</span></figcaption>
</figure>
<p>At 10x speed, the surface ants move so quickly they are a blur through which the tower underneath is visible, and the tower is slowly sinking. It happens much too slowly to discern at normal speed.</p>
<p>We observed the bottom tower layer from below through the transparent petri dish. The ants there form tunnels and gradually exit the tower. They then scurry about the tower surface until eventually they join a new top ring.</p>
<p>We couldn’t see the ants deep inside the tower. Is the entire tower or just its surface sinking? We suspected the former, as ants in clumps and rafts grip together as one mass.</p>
<p>We enlisted <a href="http://www.crablab.gatech.edu/pages/people/index.htm">Daria Monaenkova</a>, who had just <a href="https://doi.org/10.1038/521129a">invented a novel 3D X-ray technique</a>. We doped some of the ants with radioactive iodine and tracked them. Every tracked ant in the tower sank.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/gArs0-ib1WU?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">X-ray photography reveals ants (black dots) walk up the sides of the tower, only to sink when they reach the column.</span></figcaption>
</figure>
<p>Perhaps the most remarkable implication of this research is that the ants don’t have to “know” whether they are all behaving the same way. Apparently they follow the same simple rules of movement: If ants are moving above you, remain in place. If not, move randomly, and stop only if you reach an unoccupied space adjacent to at least one stationary ant.</p>
<p>Once the tower is built, the ants circulate through it while preserving its shape. We were surprised; we thought the ants would stop building their tower once its height was maximal. Previously, when we studied the ant raft, we were surprised in the opposite way. We thought the ants would circulate through the raft so as to take turns being underwater on the bottom. Instead, ants on the bottom can stay in place for weeks.</p>
<p>Every living organism I’ve studied has turned out to be more complicated than it seemed at first. Understanding how simple rules can lead to elaborate and varied structures increases our respect for the power of evolution, and gives us ideas for how to design multi-functional self-assembling robot teams. </p>
<p><em>Editor’s note: This is an updated version of an article originally published on July 11, 2017.</em></p><img src="https://counter.theconversation.com/content/80717/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Craig Tovey receives funding from National Science Foundation.</span></em></p>Researchers identified simple behavioral rules that allow these tiny creatures to collaboratively build elaborate structures, with no one in charge.Craig Tovey, Professor of Industrial & Systems Engineering and Co-Director of the Center for Biologically Inspired Design, Georgia Institute of TechnologyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/305482014-08-14T18:06:48Z2014-08-14T18:06:48ZThousand-robot swarm assembles itself into shapes<figure><img src="https://images.theconversation.com/files/56543/original/ngrgzqdn-1408027332.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Ready to march.</span> <span class="attribution"><span class="source">Michael Rubenstein, Harvard University</span>, <span class="license">Author provided</span></span></figcaption></figure><p>There is something magical about seeing 1,000 robots move, when humans are not operating any of them. In a new study published in <a href="http://dx.doi.org/10.1126/science.1254295">Science</a>, researchers have achieved just that. This swarm of 1,000 robots can assemble themselves into complex shapes without the need for a central brain or a human controller.</p>
<p>Self-assembly of this kind can be found in nature – from molecules forming regular crystals and cells forming tissues, to ants building rafts to float on water and birds flocking to avoid becoming prey. Complex forms emerge from local interactions among thousands, millions or even trillions of limited and unreliable individual elements. </p>
<p>These self-organised systems have interesting features. First, they are decentralised – that is, they don’t need a central brain or leader. Second, they are scalable – so you can add large numbers of individuals. Third, they are robust – individuals that are unreliable don’t break the system.</p>
<p>Inspired by self-assembly in nature, Radhika Nagpal, Michael Rubenstein and Alex Cornejo at Harvard University developed a self-assembling swarm of 1,024 robots. These kilobots – where a kilo stands for 1,024 – can form complex 2D shapes including a star, a wrench and the letter “k”. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/56529/original/pqx52xc2-1408022497.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/56529/original/pqx52xc2-1408022497.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/56529/original/pqx52xc2-1408022497.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=257&fit=crop&dpr=1 600w, https://images.theconversation.com/files/56529/original/pqx52xc2-1408022497.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=257&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/56529/original/pqx52xc2-1408022497.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=257&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/56529/original/pqx52xc2-1408022497.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=323&fit=crop&dpr=1 754w, https://images.theconversation.com/files/56529/original/pqx52xc2-1408022497.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=323&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/56529/original/pqx52xc2-1408022497.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=323&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">How self-assembly happened.</span>
<span class="attribution"><span class="source">Michael Rubenstein, Harvard University</span>, <span class="license">Author provided</span></span>
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<p>What makes it exceptional is that, before the kilobot, most swarms were limited to less than 100 robots. </p>
<p>When planning the kilobot, first challenge was to build a large swarm that was affordable and easy to use. This required completely rethinking how robots are designed. The constraints meant that the robot had limited capabilities. </p>
<p>They created a coin-sized robot that could move on three stick-legs using two vibrating motors. It could communicate with neighbouring robots using infrared light, signal its state by changing a colour LED and sense ambient light. </p>
<p>No GPS-like system was available for them to know their location in the environment. Instead, robots had to form a virtual coordinate system using communication with, and measured distances to, neighbours. </p>
<p>Manual manipulations of individual robots had to be minimal, imagine pressing the “on” or “off” button on 1,024 robots. The robots also needed to be easy to charge and reprogramme. Charging was initiated by sandwiching all the robots between two conductive surfaces. Reprogramming was done wirelessly through an overhead controller that would send information to all robots about experiments to run.</p>
<p>With the robots ready, the Nagpal team had to develop an algorithm which could guarantee that large numbers of robots, with limited capabilities and local communication, could cooperatively self-assemble into user-specified shapes. This is what they came up with. </p>
<p>First, all the robots are put together in an unformed blob and are given an image of the desired shape to be built. Four specially programmed seed robots are then added to the edge of the group, marking the position and orientation of the shape. These seed robots emit a message that propagates to each robot in the blob and allows them to know how “far” away from the seed they are and their relative coordinates. Robots on the edge of the blob then follow the edge until they reach the desired location in the shape that is growing in successive layers from the seed.</p>
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<p>The algorithm had to account for unreliable robots that are pushed out of their desired location or block other robots performing their functions. Nagpal’s team overcame this challenge by implementing strategies that allowed robots to rely on their neighbours to cooperatively monitor for faults. They also avoided relying too heavily on exact positioning within the shape boundaries.</p>
<p>This is the second <a href="http://www.sciencemag.org/content/343/6172/754">Science paper</a> this year on swarm robotics from Nagpal’s lab. Their previous work looked at construction of three-dimensional structures without the need for any leader using termite-inspired robots. </p>
<p>After years of research in this area, it looks like we are finally reaching a tipping point where both hardware and algorithms can build large-scale robotic swarms, at least in the labs. These swarms have the potential to help us understand natural self-organised systems by providing fully engineered physical systems on which to do experiments. They also enable the first steps towards creating artificial swarms for real-world applications, including disaster relief, environmental monitoring and maybe even art. </p><img src="https://counter.theconversation.com/content/30548/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Sabine Hauert collaborates with the Nagpal laboratory, although not on this project. She is president of RoboHub.</span></em></p>There is something magical about seeing 1,000 robots move, when humans are not operating any of them. In a new study published in Science, researchers have achieved just that. This swarm of 1,000 robots…Sabine Hauert, Lecturer in Robotics, University of BristolLicensed as Creative Commons – attribution, no derivatives.