I’ve got an article in today’s New York Times about jellyfish and their kin—known as cnidarians. Cnidarians look pretty simple, which helped earn them a reputation as simple and primitive compared to vertebrates like us, as well as insects, squid, and other creatures with heads and tails, eyes, and so on (known as bilaterians). But it turns out that a lot of the genes that map our complex anatomy are lurking in cnidarians, too. Scientists are now pondering what all that genetic complexity does for the cnidarians. They’re also using these findings to get a better idea of how the major groups of animals evolved between 600 and 500 million years ago.
For those interested some of the gory details, check out PZ Myers’s take. Be sure to follow the links to earlier comments on some of the key papers on this research, plus diagrams.
In addition, curious readers can check out:
The timing of the evolution of cnidarians and bilaterians (full text)
The evolution of diploblasty (development from two embryonic layers)
Update, 4:20 pm: PZ Myers link fixed (and spelling corrected!).
Originally published June 21, 2005. Copyright 2005 Carl Zimmer.