10/11/20
Coelacanth
There are only two known species of coelacanth (SEEL-uh-kanth), one of which lives around the Comoros Islands of East Africa and the other off the coast of Sulawesi, Indonesia. It was formerly thought that the coelacanth, previously only known from fossils, had gone extinct 65 million years ago with the dinosaurs. However, in 1938 (and the 1990s for the Indonesian coelacanth) it was found, very much alive. It took this long partly because of their rarity, and partly because they are deep sea creatures that live up to 2,300 feet under the surface. These humongous fish grow to be about 7 feet long, 200 pounds, and can live more than 60 years. Coelacanths are nocturnal and spend most of the day in caves. At night, they hunt and eat bony fishes, cephalopods, and other invertebrates. This fish has some unique features, including a mouth with a hinged joint in its skull allowing it to open its mouth extremely wide; limblike paired lobe fins that move alternately; a type of thick scales unique to ancient extinct fish; a hollow notochord on the spinal cord which is a feature of early vertebrates; and an electrosensory organ used to find food. These features are solely in the coelacanth and do not appear in any living vertebrates. These two coelacanth species and another fish called the lungfishes make a group called the lobe-finned fishes, fishes whose fins attach to short limbs instead of the body.
The coelacanth is ranked as critically endangered and extremely vulnerable to extinction. The main reasons for this is how few coelacanths there are, and how they only live in a small amount of the oceans. They also have really low natural numbers. As technology advances, the coelacanth becomes increasingly threatened by new deep-sea fisheries. Not much is known about the coelacanth’s habits because so few of these animals have been observed, and marine scientists would love to know more about these fish. The coelacanth is also interesting to historical scientists interested in learning how animals evolved to walk on land. Coelacanths have survived for millions of years, and it should not be because of humans that they go extinct.
Photo by Mark V. Erdmann
There are only two known species of coelacanth (SEEL-uh-kanth), one of which lives around the Comoros Islands of East Africa and the other off the coast of Sulawesi, Indonesia. It was formerly thought that the coelacanth, previously only known from fossils, had gone extinct 65 million years ago with the dinosaurs. However, in 1938 (and the 1990s for the Indonesian coelacanth) it was found, very much alive. It took this long partly because of their rarity, and partly because they are deep sea creatures that live up to 2,300 feet under the surface. These humongous fish grow to be about 7 feet long, 200 pounds, and can live more than 60 years. Coelacanths are nocturnal and spend most of the day in caves. At night, they hunt and eat bony fishes, cephalopods, and other invertebrates. This fish has some unique features, including a mouth with a hinged joint in its skull allowing it to open its mouth extremely wide; limblike paired lobe fins that move alternately; a type of thick scales unique to ancient extinct fish; a hollow notochord on the spinal cord which is a feature of early vertebrates; and an electrosensory organ used to find food. These features are solely in the coelacanth and do not appear in any living vertebrates. These two coelacanth species and another fish called the lungfishes make a group called the lobe-finned fishes, fishes whose fins attach to short limbs instead of the body.
The coelacanth is ranked as critically endangered and extremely vulnerable to extinction. The main reasons for this is how few coelacanths there are, and how they only live in a small amount of the oceans. They also have really low natural numbers. As technology advances, the coelacanth becomes increasingly threatened by new deep-sea fisheries. Not much is known about the coelacanth’s habits because so few of these animals have been observed, and marine scientists would love to know more about these fish. The coelacanth is also interesting to historical scientists interested in learning how animals evolved to walk on land. Coelacanths have survived for millions of years, and it should not be because of humans that they go extinct.
Works Cited
Coelacanths. (2018, September 24). Retrieved September 10, 2020, from https://www.nationalgeographic.com/animals/fish/group/coelacanths/
Coelacanth. (2018, December 20). Retrieved September 10, 2020, from https://ocean.si.edu/ocean-life/fish/coelacanth
Coelacanth. (May). Retrieved September 10, 2020, from https://oceana.org/marine-life/ocean-fishes/coelacanth
Top photo by Laurent Ballesta