Tuesday, December 23, 2008

I'm Not Dead

Last month, Phantom Midge made a wonderful suggestion for an EUT that I hadn’t thought about. I had known about it for ages, and, like her, had been pronouncing it wrong for years1. Somehow, without any foreknowledge, I’m managing to post this on an exceedingly appropriate day, as today is the 70th anniversary of its discovery as a living animal.
Image from Dinofish
Image from Dinofish

Order Coelacanth (pronounced See-la-canth) had been well documented since 1836, and fossils show that it lived for 345 million years between the Devonian period and the end of the Cretaceous period, when the dinosaurs died out. This must have come as a big surprise for the West Indian Ocean Coelacanth (Latimeria chalumnae) caught by fishermen off the coast of South Africa in 1938. These fishermen were friends with the curator of a small, local museum, and she would frequently check through their catch for anything interesting. Needless to say, something interesting was, in fact, found. Dinofish, who seem to be experts on this matter, have the whole long story on their site in far more detail than I can manage.

Coelacanths spend most of their time in deep (90-200m) caves, where they suction feed on any fish smaller than their head. Exceedingly sensitive eyes, along with an electro-sensory organ help them hunt. These are not small fish, getting up to about 6 feet in length and weighing about 175 pounds, thus surpassing the other “Living Fossil” fish I wrote about2. Coelacanth tail fins are split into three fleshy sections, and all eight of their fins move in a mesmerizing, visualized wonderfully—as always—in an ARKive video.

I was surprised the Coelacanth is listed at all, much less as Critically Endangered. I thought there would be far too little information on its numbers and habits to be called anything other than Data Deficient. Analyses of populations in 1989 suggested that there might only be 500 individuals left. The low population, ironically enough, might be attributed to by-catch. This could explain why all the natives were so perplexed when the Europeans got excited by the catch of a fish they knew to be inedible3. Since then, conservation and outreach programs have given fishermen the tools to release the fish directly back to the murky depths from which they came.

1In Freshman Zoology, I made a list of letter combinations that made an “s” sound. “Coe” always annoyed me, because I’ve never seen it outside of biology.
2Wikipedia has some nice articles about the term “Living Fossil.” Coelacanths are a “Lazarus taxon,” while the Australian Lungfish falls into the wider “Living Fossil” expression. I don’t think I’ll ever get a chance to write about an “Elvis taxon.”
3Never underestimate the local population when it comes to ecology.