Demersal fish team also reported that the appearance of the fish, unlike that of most deep sea fish, was surprisingly "cute", and that they were surprised by how active the fish were at these depths. Most demersal fish of commercial or recreational interest are coastal, confined to the upper 200 metres. Commercially important demersal food fish species include flatfish, such as flounder, sole, turbot, plaice, and halibut. Also important are cod, hake, redfish, haddock, bass, congers, sharks, rays and chimaeras. The following table shows the world capture production of some groups of demersal species in tonnes. Black sea bass inhabit US coasts
Flatfish as an early relative of the flatfish and transitional fossil. In a typical modern flatfish, the head is asymmetric, with both eyes on one side of the head. In "Amphistium", the transition from the typical symmetric head of a vertebrate is incomplete, with one eye placed near the top of the head. The researchers concluded, "the change happened gradually, in a way consistent with evolution via natural selection—not suddenly, as researchers once had little choice but to believe." Flatfishes have been cited as dramatic examples of evolutionary adaptation. Richard Dawkins, in "The Blind Watchmaker", explains the flatfishes' evolutionary history thus: