Wednesday, April 23, 2008

Preserved Coelacanth Highlights Tokyo Evolution Exhibition

A fish out of water... and out of timeA fish out of water... and out of time
Japan's National Museum of Nature and Science has acquired a preserved Coelacanth to highlight its "Darwin" evolution-themed exhibition being held in Tokyo. The Coelacanth, a fish often referred to as a "living fossil", has changed very little since the species originated approximately 380 million years ago.

Preserved specimen of a coelacanth from the Fish Division specimen collection at the Smithsonian National Museum of Natural History (photograph by Sandra J. Raredon)Preserved specimen of a coelacanth from the Fish Division specimen collection at the Smithsonian National Museum of Natural History (photograph by Sandra J. Raredon)


The Coelacanth, an odd-looking deep-water fish, caused a sensation in the scientific community when a fisherman landed one 70 years ago off the coast of Madagascar.

Fossil coelacanths have been found in rock layers dated to approximately 380 million years ago, and until its rediscovery in 1938 it was thought the species went extinct about 70 million years ago. The first coelacanths coexisted with one of the earliest vertebrates to walk on land, Ichthyostega.



Coelacanths are lobe-finned fish with bones inside their fins. It is thought that similarly built fishes evolved these movable fins into arms and legs able to support their weight on dry land, and by doing so, take advantage of a new ecological niche. As for the coelacanths themselves, their body design was so well adapted to life in the deep sea that they have changed remarkably little over an immense expanse of geological time.

Something's not-so-fishy about this fin...Something's not-so-fishy about this fin...


The "Darwin" evolution exhibition now taking place at the National Museum of Nature and Science in Tokyo features a 1.7 metre (5.5 ft) long coelacanth caught off the coast of Tanzania in 2005. The fish was preserved in resin before being put on display.

By observing this amazing "living fossil", visitors to the exhibition will be able to more fully imagine a time in our planet's remote past when the earliest human ancestors to walk the earth were gasping their first breaths. (via Yomiuri News)

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