Fossils, cells point to early appearance of the brain

Hundreds of millions of years ago, animals reached a major milestone: They acquired a brain. But just when and how that happened has been elusive, not least because paleontologists thought that the soft, fragile tissues of the central nervous system would leave few traces in the fossil record. Now, researchers have shown that such soft tissue can fossilize in the right conditions and described a complex brain from multiple 520-million-year-old fossils. That brain has the same three-part structure as modern arthropods and vertebrates. The work helps establish that brains evolved earlier than previously thought. A separate group has proposed just how that might have happened. They suggest a change in feeding strategies and the development of a protomouth were key to kicking off nervous system development.www.glorybios.com