Monday, May 17, 2010
Giant Isopod: A Trilobite for our Times?
by John MacBeath Watkins
As the owner of too many books about paleontology, a picture on the front of the Seattle Times today took me aback at first. It was a scientist holding what appeared to be a trilobite. Hey, I even owned a boat named Trilobite at one time. Perfectly respectable extinct bottom-dwelling creature.
But this was not a real trilobite. It was instead an example of convergent evolution, a giant isopod, related to wood lice and pill bugs. They are threatened by the BP oil spill in the Gulf of Mexico.
Giant isopods seem to live like trilobites, eating whatever falls to the bottom of the sea, so they adopted the same flat body form and flexible shell.
Just as New World vultures are not genetically related to Old World vultures, evolving from different birds to fill the same ecological niche, isopods are not related to the species that existed 300 million years ago to fill their niche.
More on trilobites here.
More on giant isopods here. Apparently they are served at restaurants in Taiwan.