Old Fish

I want to introduce you to the coelacanth (pronounced sea-la-kanth).

The coelacanth is an amazing fish. Amongst animals with backbones, the coelacanth is ancient. It’s been around for about 400 million years. To put that in perspective, dinosaurs were around for less than 200 million years and died out around 65 million years ago. Until 1938 coelacanths were thought to have been extinct for about 65 million years. But in 1938 someone realized the fishermen on the Comoros Islands near Madagascar were catching them!

The coelacanth has not really changed much during its 400 million year run. What’s the secret of this successful life form? One big factor is their very slow metabolism. A tuna needs 100 times more oxygen (per kilogram per hour) than a coelacanth. And, a coelacanth  can get by on 12 grams of food a day, a portion of food lighter than three US nickel coins.

Because coelacanths possess the slowest metabolic rate of any vertebrate; they can live in parts of the ocean where more active fish can’t. So coelacanths can be found flourishing on the barren undersea lava fields in the Indian Ocean which are unlike the food rich coral reefs favored by faster fish. There’s not a lot of competition for food nor is there lots of food where they live.

Coelacanths look a little bit different. They sport heavy, armor-like scales and a few more fins than most fish. Growing to almost 2 meters long, older coelacanths can tip the scales at 90 kilos. Because they have more fins than most other fish coelacanths have a unique and usually slow swimming style.

I’ve known about coelacanths for years and recently I saw a video clip of one by a German explorer, Hans Fricke. It’s hypnotizing, and I wanted to share it. Check out this short     (51 sec) video of a coelacanth just hanging out. It’s mesmerizing.