The fossilized remains of an about 520-million-year-old creepy-crawly provides a portrait of an ancient arthropod’s nervous system.
Researchers first described Chengjiangocaris kunmingensis — an ancient relative of spiders, insects and crustaceans unearthed from a fossil bed in southern China — in 2013. Further imaging and investigation of five new fossilized specimens reveal exceptionally well-preserved soft tissue and a ropelike structure running down the animal’s belly. That structure is the remains of a ventral nerve cord, Xi-guang Zhang of Yunnan University in Kunming, China, and colleagues explain February 29 in the Proceedings of the National Academy of Sciences.
In invertebrates, a nerve cord will serve the same work as our spinal-cord. In C. kunmingensis, bundles of ganglia and connective cells form the cord like in today’s tardigrades just. Each bundle probably manipulated a pair of itty-bitty legs, the researchers write. What seem to be specific peripheral nerves shoot faraway from the nerve cord, resembling the segmented nerve roots observed in male organ velvet and worms worms.
The ancient critter’s anxious system increases our knowledge of the broader development of nervous devices in contemporary invertebrates, the experts write.