The word fish is inherited from Proto-Germanic, and is related to German Fisch, the Latin piscis and Old Irish īasc, though the … See more

About 530 million years ago during the Cambrian explosion, fishlike animals with a notochord and eyes at the front of the body, such as Haikouichthys, appear in the fossil record. During the late Cambrian, other jawless for… See more

Fish species are roughly divided equally between freshwater and marine (oceanic) ecosystems; there are some 15,200 freshwater species and around 14,800 marine species. Coral reefs in the Indo-Pacific constitute … See more

The body of a typical fish is adapted for efficient swimming by alternately contracting paired sets of muscles on either side of the backbone. These contractions form S-shaped curves that move down the body. As e… See more

A shoal is a loosely organised group where each fish swims and forages independently but is attracted to other members of the group and adjusts its behaviour, such as swimming speed, so that it remains close to the other m… See more