Believe it or not, but ducks have a reputation for the unexpected: bizarre and intricate mating anatomy. According to ...

Learn how long-term mate switching helps a small beluga whale population maintain genetic diversity.

It’s not just about chromosomes. Or reproductive cells. Or any other binary metric. Many genetic, environmental and developmental variations can produce what are thought of as masculine and feminine ...

“Most sex differences in the brain are subtle and distributed,” Licht explained in a statement. “What surprised us here was the clarity of the signal. This is a discrete group of neurons that behaves ...

The cellular biology of reproduction is often depicted as an epic journey, in which millions of intrepid sperm fight to be the first to claim the ultimate prize: the chance to fertilize the egg, which ...

A duplicated gene evolved into a switch that determines sex in frogs, revealing how evolution can safely reshape critical ...

Gentlemen, here’s a question: Do you know your sperm count? While this may seem personal or even awkward, it's a conversation that's becoming more common. For years, fertility tech has focused ...