Elephants are pregnant for up to two years. Females of some fish species starve for weeks while holding dozens of eggs and hatchlings inside their mouths. And pregnant humans commonly endure months of ...

A large-scale analysis of 117 mammal species found that preventing reproduction is associated with longer lifespans, suggesting a strong link between reproductive activity and life expectancy. Why do ...

Reproduction is central to survival, but it may come at a hidden cost. In a new study, which drew on zoo records from more than 110 animals around the world, researchers found that blocking ...