Dorsal fin of an orca

A dorsal fin is a fin located on the backs of fishes, whales, dolphins, and porpoises, as well as the (extinct) ichthyosaurs. Its main purpose is to stabilize the animal against rolling and assist in sudden turns. Some animals have developed dorsal fins with protective functions, such as spines or venom. Many catfish can lock the leading ray of the dorsal fin in an extended position to discourage predation or to wedge themselves into a crevice. Dorsal Fin or the orca whale, thanks to the NOAA Photo Library http://www. ... Dorsal Fin or the orca whale, thanks to the NOAA Photo Library http://www. ... Binomial name Orcinus orca Linnaeus, 1758 Orca range (in blue) The Orca or Killer Whale (Orcinus orca) is the largest species of the oceanic dolphin family (Delphinidae). ... A fin is a surface used to produce lift and thrust or to steer while traveling in water, air, or other fluid media. ... A giant grouper at the Georgia Aquarium Fish are aquatic vertebrates that are typically cold-blooded, covered with scales, and equipped with two sets of paired fins and several unpaired fins. ... A Fin Whale The term whale is ambiguous: it can refer to all cetaceans, to just the larger ones, or only to members of particular families within the order Cetacea. ... Genera See article below. ... Genera Neophocaena Phocoena - Harbor porpoise Phocoenoides - Dalls porpoise The porpoises are small cetaceans of the family Phocoenidae; they are related to whales and dolphins. ... Families Ichthyosauridae Leptonectidae Mixosauridae Ophthalmosauridae Shastasauridae Stenopterygiidae Teretocnemidae Ichthyosaurs (Greek for fish lizard - ιχθυς meaning fish and σαυρος meaning lizard) were giant marine reptiles that resembled fish and dolphins. ... Families Akysidae Amblycipitidae Amphiliidae Anchariidae Andinichthyidae â€  Ariidae Aspredinidae Astroblepidae Auchenipteridae Austroglanididae Bagridae Callichthyidae Cetopsidae Chacidae Clariidae Claroteidae Cranoglanididae Diplomystidae Doradidae Erethistidae Heptapteridae Hypsidoridae â€  Ictaluridae Lacantuniidae Loricariidae Malapteruridae Mochokidae Nematogenyiidae Pangasiidae Pimelodidae Plotosidae Pseudopimelodidae Schilbeidae Scoloplacidae Siluridae Sisoridae Trichomycteridae incertae sedis   Conorhynchos   Horabagrus   Phreatobius Catfish (order Siluriformes) are a very diverse...

Dorsal fins come in a variety of shapes and sizes.

They are infamous for being the sign of an approaching shark. Orders Carcharhiniformes Heterodontiformes Hexanchiformes Lamniformes Orectolobiformes Pristiophoriformes Squaliformes Squatiniformes Symmoriida(extinct) Sharks (superorder Selachimorpha) are fish with a full cartilaginous skeleton[1] and a streamlined body. ...

The human dorsal fin is located directly below the flagellum. Trinomial name Homo sapiens sapiens Linnaeus, 1758 Humans, or human beings, are bipedal primates belonging to the mammalian species Homo sapiens (Latin: wise man or knowing man) in the family Hominidae (the great apes). ... // A Flagellum (plural: flagella) is a long, slender projection from the cell body, composed of microtubules and surrounded by the plasma membrane. ...

Whales, dolphins, and porpoises

In relation to the size of the creature, the dorsal fin of the male orca is quite large, as much as 1.8 m high. (The female orca has a shorter dorsal fin that is more curved.) Many (30-100%) captive male killer whales (orcas) experience collapse of the dorsal fin, possibly because lack of exercise through turning leads to diminished muscle tone, other possible factors include change in diet, sex drive and pressure in the pool due to counter-clockwise swimming, this reacts with the sodium nitrate in the whales pituatary gland and leads to the loss of connective tissue in the dorsal area (Only about 1% of wild orcas have collapsed dorsal fins.) The dorsal fins of most other whales are relatively small. The bowhead whale has no dorsal fin at all, as an evolutionary adaptation to its life spent cruising under icepack. The dorsal fins of whales develop distinctive nicks and wear patterns with time, and this fact is used by wildlife biologists to identify individuals in the field. Binomial name Orcinus orca Linnaeus, 1758 Orca range (in blue) The Orca or Killer Whale (Orcinus orca) is the largest species of the oceanic dolphin family (Delphinidae). ... A top-down view of skeletal muscle Muscle (from Latin musculus little mouse [1]) is contractile tissue of the body and is derived from the mesodermal layer of embryonic germ cells. ... Binomial name Linnaeus, 1758 Bowhead whale range The bowhead whale (Balaena mysticetus), also known as Greenland Right Whale or Arctic Whale, is a marine mammal of the order Cetacea. ... This article is about evolution in biology. ... A wildlife biologist is someone who studies wild animals and their habitats. ...