While a dominant male fish from northern Mexico mates with a female, a small fella bides his time in the offing. Suddenly, the little guy darts in ahead of Mr. Big and plants his seeds on freshly laid ...

Goldfish “cuddling” is often a sign of breeding behavior, where one fish closely follows or nudges another as part of mating ...

A new study has found that chemical additives in everyday plastic might be stopping – or, at best, interrupting – the reproductive habits of a shrimp-like species that is key to the marine food chain.