Male seahorses have quietly rewritten one of biology’s most familiar scripts, shifting the burden of pregnancy and birth onto fathers and turning paternal care into a full‑body commitment. Their ...

In seahorses, it is the males who carry offspring to term. The females lay their eggs into a special brood pouch on the bellies of the males where they are fertilized by the male's sperm. In the brood ...

Iron deficiency during pregnancy can cause a male mouse embryo to develop female features, a new study reveals. The low iron disrupts the activation of a key gene that spurs the development of male ...

It’s a common belief in the world of deer that males have antlers and females don’t, but reindeer serve as the exception. Both male and female reindeer grow antlers. This is a trait that no other ...