Shelf Life: Six ways to prepare a coelacanth
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Version 0 of 1. Coelacanths originally appeared in the fossil record between 415-360 million years ago. The first specimen was discovered and described from a fossilised tail in 1839 by biologist and geologist, Louis Agassiz. Originally thought to have gone extinct alongside the dinosaurs 66 million years ago, no one dreamt that coelacanths might still be alive today. So the scientific world was astonished when a live specimen was caught by local fishermen on the coast of East London in South Africa on 22 December 1938 -- the first (and so far, only) time that an extant animal has been first discovered in the fossil record. To the best of our knowledge, two species of coelacanths are alive in the world today; the West Indian Ocean coelacanth, Latimeria chalumnae, and the Indonesian coelacanth, Latimeria menadoensis, which was discovered in an Indonesian fish market in 1997. Both species have small populations and are thought to be endangered, probably due to overfishing by local fishermen who accidentally catch coelacanths whilst fishing for oilfish. (Coelacanths are inedible; their flesh sickens people.) Today, the American Museum of Natural History in New York City is one of a number of institutions around the world that house and care for coelacanth specimens. The AMNH obtained its first West Indian Ocean coelacanth in 1962, a specimen now known as catalog number 32949. It remained in a tank in the Ichthyology Department for 13 years before any invasive scientific studies were done. In 1975, a haematologist from Long Island was granted permission to open up the belly of this fish to obtain a tissue sample for some comparative research he was doing. Catalog number 32949 held a surprise: she was pregnant. On this initial dissection, the researchers found three foot-long embryonic coelacanths, complete with an egg sac attached. (A later dissection found two more embryos.) This discovery revealed that female coelacanths retain the fertilised eggs in their bodies until after the embryos hatch, and then give birth to live, free-swimming young; a life history strategy known as ovoviviparity. These pups, as the young are known, are miniature versions of adults. Although these fish remain enigmatic, our knowledge of coelacanth life history is still progressing, often due to research on specimens held in museum collections. When coelacanths and other biological specimens are preserved and cared for properly, they continue to provide insights and inspire questions for hundreds of years. In this video, the third instalment in the Shelf Life series, Ichthyology Curator Melanie Stiassny tells the story of the Museum’s first coelacanth and offers a primer on specimen prep: Watch the previous video in this series. You are invited to visit the AMNH’s dedicated Shelf Life site. AMNH can be found on twitter @AMNH. .. .. .. .. .. .. .. .. .. .. .. GrrlScientist is very active on twitter @GrrlScientist and sometimes lurks on social media: facebook, G+, LinkedIn, and Pinterest. |