In most vertebrates, the absence of adaptive immunity would be catastrophic, but in some deep-sea angler fish species, it enables their “wild” and “wacky” mating habits.

Fossils from Newfoundland, Canada, reveal the extensive connections that existed among Earth’s earliest, sea-dwelling animals.

Before the joey is born, another pregnancy has already started.

A phthalate commonly found in shampoos, cosmetics, and cleaning products disrupts reproduction in worms.

Building simulations based on real genetic data, researchers conclude Gattaca-like tactics to choose the traits of future offspring would yield little payoff.

A protein present in the ejaculate of male fruit flies activates long-term memory formation in the brains of their female partners.

It could be a throwback to a mechanism that induces ovulation during sex, researchers propose, but not everyone thinks the results can be extrapolated to people.

Groups of corals release all of their eggs and sperm once a year, but the timing of their spawning is under threat from climate change.

Funnel-web spiders change the timing of their distinct courtship behavior depending on what microbes they’re carrying.