Scientists have discovered the earliest known evidence of the structures that eventually became spider fangs in a fossil dating back 518 million years. The finding was made by researchers from Yunnan University and the University of Leicester. The Ancient Origins of Spider FangsSpiders belong to a large group of invertebrates called chelicerates, which also includes scorpions and ticks. X-Rays Reveal Preserved Soft AnatomyResearchers from Yunnan University, China, and the University of Leicester used X-ray technology to examine the rock surrounding the fossil. The research was led by Professor Yu Liu of Yunnan University, who is also a Visiting Professor at the University of Leicester.