London: A new study has identified one of the oldest fossil brains ever discovered – more than 500 million years old – and used it to help determine how heads first evolved in early animals.
These fossils originated from the Burgess Shale in western Canada, one of the world’s richest sources of fossils from the period. The findings identified a key point in the evolutionary transition from soft to hard bodies in early ancestors of arthropods, group that contains modern insects, crustaceans and spiders, Medical Xpress reported.
“The anterior sclerite has been lost in modern arthropods, as it most likely fused with other parts of the head during the evolutionary history of the group,” Javier Ortega Hernandez, researcher from Cambridge University’s department of earth sciences, who authored the study, said.
A hard plate, called the anterior sclerite, and eye-like features at the front of their bodies were connected through nerve traces originating from the front part of the brain.
“But what we’re seeing here is an answer to the question of how arthropods changed their bodies from soft to hard. It gives us an improved understanding of the origins and complex evolutionary history of this highly successful group,” he added.