There are concerned, overprotective parents, and then there are cichlid fish. After a male cichlid fertilizes the female’s eggs, she holds her entire brood of embryos inside her mouth for two weeks ...

A few hundred thousand years ago, a group of fish in an African lake evolved something new—a set of strong chewing jaws in their throats. They became better at eating a wide variety of tough foods.

Africa’s deepest freshwater lake holds a dizzying array of animals, including hundreds of species of cichlid fish found nowhere else in the world. They crowd the waters of Lake Tanganyika, with scales ...

Cuckoo catfish may be the worst parents ever. Rather than raising their own cannibalistic offspring, they force other fish species to raise them in their own mouths. But how do they do it? New ...