Image Of The Day: Weird Fish Not So Weird After All

It turns out lampreys, long thought to have taken a different evolutionary road than almost all other backboned animals, may not be so different after all, especially in terms of the genetics that govern their skeletal development.

Researchers from the University of Florida found that the same essential protein that builds cartilage in this odd animal is none other than collagen. This vital structural molecule is found in all vertebrates with backbones and jaws, including humans.

The results indicate the collagen-based skeleton evolved before the jawed and jawless vertebrates split into different paths, not afterward. In addition, the research shows that scientists have to dig beyond bone and cartilage to unravel vertebrate relationships, according to Michael Caldwell, Ph.D., an associate professor of earth and atmospheric sciences and of biological sciences at the University of Alberta.

Lampreys live today in the Great Lakes and other freshwater bodies that connect to the sea. They spend the first five years of their development in the larval stage before finally morphing into a boneless fish. Lampreys are considered a nuisance, largely because of their unsettling appearance and demeanor - picture a leech longer than your forearm with a rasp-like mouth that flares open at the end of its body.

The study will be detailed online in the journal for the Proceedings of the National Academy of Sciences.

--Ker Than

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Credit:  Great Lakes Fishery Commission