It’s really difficult to pick a single prehistoric animal as one’s favorite. Perhaps choosing a group might be easier so that’s the way I’ll get around this question, otherwise I’d have a list as long as my arm – well, OK, maybe longer. The group will have to be, insert drum roll here, the ‘Pterosaurs of the Mesozoic’. You likely saw that one coming due to the image in the left sidebar and the side bar link grouping.
Ornithocheirus on Chinese Dinosaur Park postcard
They’re a very varied group, and that’s what makes them so interesting. They maintain a mystical origin as they could have developed from as many as four different areas on the tree of life. They’re not birds, not dinosaurs and definitely, at least at the moment, not part of any other grouping. Of all sizes and shapes, weighing next to nothing, they sailed the prehistoric skies as the first aviators to conquer the air, they could fly! How cool is that?
Zhejiangopterus in Chinese commemorative cancel *
The above Chinese postmark from Linhai, Zhejiang Province commemorates the 20th Anniversary of the discovery of the ‘Fossil of South-Changliang-River Pterosaur‘.
OK, OK, yes, I do have other interests like sabertooths (sabretooths), archaeopteryx, giant dragonflies, trilobites, jellyfish, ants in amber, cavemen, cave paintings of France and Spain, maybe a few dinosaurs or even a fish with big teeth. But as neat as all those are, none are quite as cool as a pterosaur. 
* NOTE: Assistance with identification of this cancel provided by PaleoPhilatelist – thanks.
The Mesozoic Times 