A newly discovered fossil from Devon has provided rare insight into the appearance of the earliest members of the lizard lineage, and the findings include some unexpected traits, according to researchers at the University of Bristol.

Today, lizards, snakes, and the tuatara of New Zealand together form the Lepidosauria, the most diverse group of living land vertebrates, boasting more than 12,000 species — surpassing both birds and mammals. This remarkable success raises questions about which characteristics enabled their evolutionary advantage.