[Image: Pteranodon by Larry Felder]
Pterosaur Myths Busted (V2.0!)
Pterosaurs are a staple of movies featuring prehistoric animals, yet most media depictions of the poor beasts remain woefully stuck in the 19th century. In reality, there was much more to these astonishing animals than many of us could have gleaned from the sluggish flimsy-winged gliders of our childhoods. Here we take a look at how some common misconceptions about pterosaurs stack up against the facts.
Misconception: “Pterodactyl” and “pterosaur” mean the same thing.
Fact: “Pterosaur” applies to the entire group, but “pterodactyl” is only correct when used in reference to the subgroup Pterodactyloidea.
M: Pterosaurs were dinosaurs.
F: Dinosaurs fall under the orders Ornithischia and Saurischia. Pterosaurs do not belong to either group, though current evidence places them as close relatives of the dinosaurs within Ornithodira.
M: Pterosaurs were the ancestors of birds.
F: Birds are a lineage of theropod dinosaurs which first appeared in the Jurassic. Unlike dinosaurs, pterosaurs left no living descendants.
M: Pterosaurs were scaly.
F: Though the pads of their feet had scales, most of a pterosaur’s body was covered in hairlike filaments called pycnofibers. Pterosaurs of the primitive family Anurognathidae, such as the one shown below, seem to have been fluffed up from snout to tail with pycnofibers.
M: Pterosaurs were cold-blooded.
F: Nope. With no body heat to insulate there wouldn’t be much point to pycnofibers.
M: Pterosaurs could pick things up with their feet.
F: Their feet were largely inflexible and much better suited to walking than grasping. Like humans, they employed plantigrade locomotion—in other words, the entire sole of the foot contacted the ground as they walked.
M: Grounded pterosaurs walked on their hind legs/could only crawl around on their bellies.
F: They were quadrupeds, and most were quite adept at ground locomotion to boot. Some, such as the dsungaripteroids, may even have been capable of galloping. The three in the illustration below are shown badgering an azhdarchid for its kill.
M: All pterosaurs had teeth/were toothless.
F: Pterosaurs had all kinds of dental arrangements, from completely toothless to jaws positively bristling with the things—just look at Pterodaustro. (Pteranodon was toothless, by the way, hence the genus name meaning “toothless wing”.)
M: All pterosaurs had long tails.
F: Long tails were apparently restricted to the earlier, non-pterodactyloid pterosaurs.
M: Females of crested species had large head crests like the males.
F: Head crests were probably sexually dimorphic, with males usually having much larger, more elaborate cranial decoration, as demonstrated by these two Darwinopterus.
M: The wing membranes were leathery, flimsy and prone to tearing.
F: Pterosaur wings were complex, multilayered structures, supple and reinforced with closely-packed fibers called aktinofibrils.
M: Each wing was supported by several fingers like a bat’s.
F: Only the hugely elongated fourth finger supported the wing; the other three fingers were much smaller. See here.
M: Pterosaurs had sharply-pointed wingtips.
F: Such a wing shape would have made flight difficult. The wingtips were rounded.
M: Some pterosaurs were too big/heavy to fly.
F: Even the largest pterosaurs were probably capable of powered flight.
M: Pterosaurs could only take off by falling off a cliff/tree/[insert high starting point here].
F: They could take off under their own power using all four limbs. See this video.
M: All pterosaurs were ocean-going fish hunters.
F: They occupied a variety of niches, and many lived inland.
M: Pterosaurs cared for their hatchlings in much the same way as modern birds.
F: Other than protecting them during the hatching process, pterosaur parents might not have had much to do with their offspring (called “flaplings”) since they were independent almost immediately after birth.
M: Pterosaurs went extinct because they were outcompeted by birds.
F: The evidence for this idea is weak at best.
M: Live pterosaur sightings indicate that the group never really went extinct.
F: This assertion relies on scant evidence as well.
If you have anything more than a passing interest in pterosaurs, you really should pick up a copy of paleontologist Mark Witton’s new book on them. Wikipedia and Pterosaur.net are other useful resources of information about these fascinating, ridiculous creatures.
Sources to avoid include David Peters’ Pterosaur Heresies and ReptileEvolution.com. While these sites look professional on the surface and feature loads of attractive artwork, scientists have been unable to replicate the results of his research, and replicable results are a hallmark of good science. Read more about Peters here (PDF), here and here.
(Credit: Other than the Pteranodon up top, all illustrations in this post are by the ever-awesome Mark Witton.)
The best kind of -saurs.