A new study posits that same-sex sexual behavior developed to help primates in complex social groups ease tension, reduce ...

Homosexual behavior in primates has a deep evolutionary basis and is more likely to occur in species that live in harsh ...

In truth, it is not a paradox. The animals involved all seem perfectly eager participants in heterosexual behaviour, as well, so their reproduction is not compromised. It is, though, a puzzle—for ...

The study found that bird species who nest in tree cavities have independently evolved heightened aggression across lineages, particularly in females. Scientists have long wondered whether evolution ...