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What researchers don't know about pterosaurs still far outweighs what they do know, but at least some of the dark corners of pterosaur life are beginning to divulge their secrets. A group of fossils discovered in Chile, for example, hints that pterosaurs may have nested in colonies. Some pterosaurs, like some birds, were crowned with dramatic crests that probably played a role in sexual display. But reconstructing their lost world is made difficult by the vagaries of fossil preservation and by the fact that these winged reptiles were evolutionary dead ends and left no descendants. Pterosaurs, for this reason, will forever remain wondrously strange. "In the living world," says Peter Wellnhofer of Munich's Bavarian State Collection for Paleontology and Historical Geology, "there's nothing really comparable to a pterosaur."
--Reported by Andrea Dorfman/New York