Imagine a world where the boundaries between “fish” and “not-fish” blur, where the ancestors of birds and mammals once swam ...

Scientists reveal the genetic secret behind the thick lips of African cichlids, linked to parallel evolution and proteins.

This clip could be used as an introduction to fish. Pupils could be asked to list the characteristics of fish and compare them with characteristics of other animal groups. This clip is relevant ...

Researchers discovered tiny features on sculpins' fins which may enable them to cling firmly in harsh underwater environments.

For this, scientists use something called an "outgroup", a living descendant that still shares many of the ancestor's primitive traits. So we need a living jawless fish, like a lamprey.

A scientific study in Britain says chemicals flushed through the drainage system have caused about 20% of male freshwater fish to exhibit female characteristics. Researchers identified more than ...

Betta fish—also known as Siamese fighting fish ... and tendency to fight. These characteristics are much more pronounced in captive betta, which have been bred for those traits since the ...

These signs demonstrate contrasting traits and adaptability due to their ... Pisces, represented by two fish swimming in opposite directions, embodies the duality between fantasy and reality.

The Locust Fork darter is slightly bigger, but the fish are both fairly small, each averaging about 1.5 inches long, researchers said. “Pigmentation patterns and coloration are traits that have ...