Very little was known about the evolution of pterosaurs – such as how they evolved to fly – but now researchers are saying that they have identified the “missing link” in their family tree. A small reptile called lagerpetid may be the closest-known relative to pterosaurs found to date. There is, however, a significant difference between the two species which is that lagerpetids didn’t fly. Since the 1700s, many fossils belonging to pterosaurs have been unearthed – they dated back to between 220 million and 65 million years ago. Pterosaurs were archosaurs – a name that translated from the ancient Greek word meaning “ruling lizard”. Archosaurs were a group that included dinosaurs, crocodylians, and birds as well as pterosaurs. They first showed up around 250 million years ago in the late part of the Permian period.