Living fossil, important stage in the evolution of tetrapods.
Latimeria, coelacanth, West Indian Ocean coelacanth, prehistoric creature, fossil, living fossil, homology, abyssal, animal, fishes, fish, vertebrates, predator, biology
The West Indian Ocean coelacanth is one of two extant species of the coelacanth order, which was formerly believed to be extinct. It was discovered in 1938. It is mostly found in the Indian ocean, along the east coast of Africa, in a depth of about 150-700 m (492.1-2,297 ft). Its body length may reach 2 m (6.56 ft), its mass about 95 kg (209.4 lb). It is a predatory fish. Its paired fins have muscular lobes at base and contain bones.
The ancestors of amphibians evolved from ancient coelacanths in the Devonian period (416–359 million years ago). During the evolution the pectoral fin of the coelacanth became adapted to moving on dry land, thus the animal became able to leave the water for short periods of time.
Later the pectoral and ventral fins evolved into legs. The steps of this process is proved by a large number of fossils. The limbs of tetrapods (four-limbed terrestrial vertebrates) are homologous with the pectoral and ventral fins of coelacanths: they have evolved from the same ancestors. Ancient coeltacanths are the ancestors of all present-day terrestrial vertebrates (including humans) and the extant coelacanth species. Coelacanths are considered ´living fossils´ due to the lack of significant changes over the past millions of years and no close relatives.