A recent Trump executive order defines sex based on gamete size. But the order oversimplifies genetics, hormones and reproductive biology.

Sex is real, and it matters. In sport, this elemental truth cannot be affirmed loudly enough. It is impossible to mount any ...

To uncover what drives sexual behavior in animals, researchers studied the brain activity of male mice throughout the series of actions involved in sex leading up to ejaculation.

Sex is not one single, simple, uniform biological reality, so biology cannot be invoked as a basis for “immutable” legal ...

"I'm not aware of any measure you can make of the human brain where the male and female distributions don't overlap," ...

While unfortunate for the males, becoming a post-sex meal offers the females vital nutrients needed to sustain themselves and ...

The pioneering research of UC Santa Cruz’s Upasna Sharma to determine how a father’s life experiences and environment can influence the health and wellbeing of his children moves forward with the ...

Female black widows sometimes eat their mates after copulation. Female praying mantises are known for biting off the male's ...

A team of neurologists, environmentalists and bioengineers at the University of Queensland, in Australia, has found that male ...