A biologist at Washington University in St. Louis has shown that for some fish species, females prefer males with larger sexual organs, and actually choose them for mating. That does not exclude males ...

In many fish species body size plays an important role in sexual selection. Large individuals are preferred mating partners because they can enhance offspring survival by providing better quality ...

PENYABANGAN, Indonesia — It took a broken air conditioner for Tom Bowling to figure out — after nearly eight months of failure — how to breed the coveted pink-yellow tropical fish known as blotched ...

"Each spring, all adults of the species migrate to one site, the Colorado River Delta in the uppermost portion of the Gulf [of California], to form one spawning aggregation of several million fish," ...

Grunions are the only fish in the world that come out of the water and burrow into the sand to lay their eggs. Their complicated mating ritual can be watched along Southern California to Baja ...

Walk into any pet or aquarium store, and you’re going to find clownfish. That orange-and-white-striped Nemo is practically synonymous with saltwater aquariums, and it’s one of the first fish new ...