In romantic circles, reproduction is viewed as a harmonious venture between the sexes. After all, if you aim to produce the best offspring possible, wouldn’t it also be best to cooperate with your partner…
It turns out guppy genital length is genetic – for females as well as males.
Alice Chaos
It’s not always easy to tell if a fish is male or female: they look more or less the same. But there are exceptions, such as guppies and, as with humans, guppy genitalia varies in size across the species…
We use a range of hormone-induced indicators to determine who is male and who is female on a daily basis.
European Parliament
What is a male? What is a female?
If you were to conduct a survey, most people would probably have little difficulty expressing some fundamental differences. After all, we learn to tell boys apart from…
Researchers applied sunblock to the plumage of female blue tits to see how males reacted.
Marko_K
Rearing young is a costly business that often affects an individual’s own future survival or reproduction prospects.
And so it makes sense for individuals to find ways to ensure the energy they spend…
Here’s some good news: having more sexual partners makes females more fertile.
A recent study on Trinidadian guppies has shown that females who mate with multiple males produce more grand-offspring than…
Feel free to bust out some tunes, but you won’t fool the children of the evolution.
Verano y mil tormentas
What transforms noise from album filler to dancefloor killer? Why do some tracks turn us on while others make us tune out?
DarwinTunes, a computer program that employs the principles of natural selection…
Female wasp spiders often eat their mate straight after intercourse.
Wikimedia Commons
When it comes to selecting a mate, females are traditionally thought of as the choosy sex; males, meanwhile, aren’t thought to be particularly picky.
This makes sense for many species – the sex that invests…
Humans and spider monkeys are the only primate species without a penis bone.
Chris Makarsky
The penis. It comes in so many different shapes and sizes … and that’s just in humans. As you would imagine, different species have very different penises.
The males in most mammal species, including…
Chemical cues may act as matchmakers for sperm and ova.
wellcome images
On the face of it, a sperm’s work seems pretty straightforward: locate an egg and fertilise it. Job done.
But in the world of a sessile broadcast-spawning marine invertebrate – immobile organisms in which…