Oldest Arthropod Brain is Surprisingly Complex

Photo: Xiaoya Ma

My, what large fossilized brain you've got! Nicholas Strausfeld of the University of Arizona and colleagues were studying fossils from China's Yunnan province when they encountered a 520-million-year-old brain ever found in an arthropod (a group of invertebrates that includes insects and crustaceans):

This complex, insectlike brain suggests that rather than insects arising from simple branchiopods, today's arthropods descend from a complex-brained ancestor. Branchiopods would later have shed some of this complexity, Strausfeld said, while other crustaceans and insects kept it. In fact, he said, the brain may have evolved to segment into three parts very early on; mammals, including humans, have a forebrain, midbrain and hindbrain, suggesting a common organization.
"Lots of people don't like that idea, sharing a brain with a beetle, but there's good evidence suggesting that you do," Strausfeld said.

Stephanie Pappas of LiveScience has the post: Here