Search results
Results from the WOW.Com Content Network
Dorsal fin of a shark. A dorsal fin is a fin located on the back of most marine and freshwater vertebrates within various taxa of the animal kingdom.Many species of animals possessing dorsal fins are not particularly closely related to each other, though through convergent evolution they have independently evolved external superficial fish-like body plans adapted to their marine environments ...
Fins allow the sharks to be able to guide and lift themselves. Most sharks have eight fins: a pair of pectoral fins, a pair of pelvic fins, two dorsal fins, an anal fin, and a caudal fin. Pectoral fins are stiff, which enables downward movement, lift, and guidance. The members of the order Hexanchiformes have only a single
Dorsal fins: Located on the back of the fish, dorsal fins serve to prevent the fish from rolling and assist in sudden turns and stops. Most fishes have one dorsal fin, but some fishes have two or three. In anglerfish, the anterior of the dorsal fin is modified into an illicium and esca, a biological equivalent to a fishing rod and lure.
Dorsal fin of a chub (Squalius cephalus) The dorsal fins are located on the back. A fish can have up to three dorsal fins. The dorsal fins serve to protect the fish against rolling, and assist it in sudden turns and stops. In anglerfish, the anterior of the dorsal fin is modified into an illicium and esca, a biological equivalent to a fishing ...
The skeleton is cartilaginous. ... There is an erectile spine in front of the dorsal fin, sometimes poisonous. There is no stomach (that is, the gut is simplified and ...
It is also possible that the fin spine could be a unique distribution of dermal skeleton and thus derived from neural crest. Following this assumption, the brush would be a fin-baseplate extension. The endoskeletal location and absence of fin radials supports the latter hypothesis. [12] [13]
For premium support please call: 800-290-4726 more ways to reach us
They each have a highly modified skeleton formed into armored plating. This dermal skeleton has several longitudinal ridges, so a vertical section through the body looks angular, not round or oval as in the majority of other fishes. [2] A dorsal fin is always present, and is the principal (in some species, the only) organ of locomotion.