A comb jelly (University of Florida).
A scientist in Florida who studies simple sea animals known as comb jellies says he has discovered a path to a new form of brain development that may one day lead to treatments for Parkinson's, Alzheimer's and other neurodegenerative diseases.
Comb jellies, or ctenophores, look like tiny disco balls and propel themselves around oceans using specialized hairs, lapping up small prey with their sticky tentacles. “They are aliens who’ve come to Earth,” says Leonid Moroz, a neuroscientist at the University of Florida in St Augustine.
The genome of the Pacific sea gooseberry (Pleurobrachia bachei)…adds to the mystery of ctenophores. The sequence omits whole classes of genes found in all other animals, including genes normally involved in immunity, development and neural function. For that reason, the researchers contend that ctenophores evolved a nervous system independently.
Leonid L. Moroz/Mathew Citarella
His findings are published in this week's edition of the journal Nature.
Traditional scientific reasoning has held that simple nerve nets evolved all the way up to a human level of complexity along a single path. But it now appears that comb jellies took a different route, using neurochemical language that does not exist in other animals.
"All other animals have the same chemical language and these guys have completely different language. It's not only different grammar. It's a different alphabet," Moroz said.
You can listen to a Nature podcast on the findings here.
