Marjorie Courtenay-Latimer was the curator of a natural history museum in East London. In 1938 a local fisher brought a curious fish specimen which was to become a major discovery in evolutionary biology. Latimer described the fish as Latimeria chalumnae. The fish was over 1 m long, bluish in color. Most interestingly it had fleshy fins that resembled the limbs of terrestrial vertebrates.
The discovery was a hugely interesting one. Lobe-finned fishes were thought to have been extinct. Scientists knew them only from fossils and there it was a lobe-finned fish! Coelecanths morphology is amazingly similar to the fossils going as far back as 415 million years. The youngest fossil record of the lobe-finned fishes were dated to Late Cretaceous (70 million years ago). Latimeria continues to be the only living member of the lobe-finned fishes.
A second specimen was discovered 15 years after its first discovery. It again amazed everyone because this time the fish came from the Comoros Islands in the Indian Ocean. In 1997 a second coelacanth species (Latimeria menadoensis) was discovered in Indonesia which showed that descendents of coelecanths were not limited to a particular geographic location. Until now more than 309 individuals have been recorded.
Coelecanth has been considered as our last fish ancestor. This means that it may have been the ancestor of the fish that emerged out of water to colonize land. It is in a way a prequel to the Tiktaalik fossil beautifully articulated in the three part documentary "Your Inner Fish".
Anglické znění.
Coelacanth: The Fish That Time Forgot (2001)
2016-12-21T05:07:00+01:00
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