While female green hermit hummingbirds have curved bills, males’ straighter mouthparts are built for stabbing one another, a ...

Researchers have developed a new "color-coded" genetic method that makes it easy to distinguish male and female mosquitoes.

The sex of many turtles, crocodilians, and other reptiles is determined by the temperature at which their eggs incubate.

New research has mapped the cell types that specialize to form reproductive organs in both sexes, identifying key genes and signals that drive this process. The findings offer important insights into ...

Combat roles in the Marines have had gender-neutral requirements since 2015. A new policy extends that rule to fitness test scores.

The monogamy rate in humans may be higher than you expected... but we do it in a strange way compared to other animals.

Think telling sparrows apart is just not worth the effort? Our tips might change your mind. Identify sparrows by habitat, ...