Ancient arthropod brains surprise paleontologists

Exceptionally well preserved 520-million-year-old arthropod brains overturn the old idea that nervous tissue does not fossilize, and provide fresh insights into brain evolution

At first glance, the term 'neuropaleontology' may seem like an oxymoron. The neuro- prefix means something related to the nervous system, and paleontology is the scientific study of what fossilized animal and plant remains tell us about the evolution of life on Earth. Brain tissue is soft and wet, however. It usually begins to decompose minutes after death, and rarely, if ever, leaves any trace in the fossil record.

Or so we thought. The recent discovery of preserved brain tissue in a small shrimp-like creature that lived some 520 million years ago challenges this conventional wisdom, however. It provides the most convincing evidence yet that brains can indeed fossilize, as well as valuable insights into how complex brains evolved, and how the arthropods are related to one another.