March 6th

The Flying Reptiles

The dinosaurs shared the Mesozoic era with a number of other animal groups that have become so famous that they are often mistaken for true dinosaurs. Dinosaurs, as we’ve seen previously, are defined by characteristics of their limbs, ankles, and hips. From a general standpoint, their legs are held directly beneath them, unlike the splayed-out stance of lizards and crocodilians. So if you’re an animal that has a different set of characteristics, you’re not a dinosaur.

Which leads us to pterosaurs–the flying reptiles. Yes, almost everyone knows what a Pterodactyl is. But it’s not a dinosaur. It belongs to a very strange and specialized group of animals that are cousins of dinosaurs. A pterodactyl was the first  member of this family to be identified–and was scientifically described in 1809 (15 years before the first dinosaur, Megalosaurus, was entered into the literature by William Buckland).

So what makes pterosaurs special? Pterodactyl means ‘wing finger’ and that’s the key to understanding pterosaurs.

Take a moment and realize the achievement of the pterosaurs. Long before birds and bats, they were the first flying vertebrates. Before pterosaurs, insects had the skies to themselves. The pterosaurs began with long tails and short, insect-catching jaws. But by the end of the Mesozoic, some pterosaurs, like Quetzalcoatlus, boasted wing spans of nearly 40 feet–the size of a small airplane–and sported giant head crests, while losing their rudder-like tails.

They are among the most amazing creatures in the fossil record for their sheer diversity–some had teeth, others plain bills, others bristle-like, filter feeding apparatus (similar to flamingos). They seem to have adapted to many ecological niches and persisted until the end-Cretaceous mass extinction event. They must have been quite a sight, soaring gracefully above the dinosaurs. And though they were a part of the dinosaurian world, they were not the same. They belong to a group of their own.

Over the next few days, we’ll continue looking at dinosaur contemporaries that are NOT dinosaurs. Until tomorrow, share your favorite pterosaur photos with us on Facebook and Twitter using the hashtag #TDIDinos.