Are Birds Retpiles. Snakes, lizards, turtles, crocodilians, and birds are reptiles. For centuries, many scientists hypothesized that birds were reptiles due to similarities in their anatomy, but there was no hard fossil evidence to support it.
Now, i can hear you saying “but we learned that they are a different group of organisms, and that reptiles are just those scaly animals that have cold blood?” while reptiles don’t have cold blood per se, some of them do have feathers. However, birds belong to a classification of vertebrates known as ‘aves’ in the animal kingdom. The sauropsid line split into diapsids and anapsids (anapsids are all extinct now).