Pteranodon
{{Taxobox
color = pink | name = Pteranodon | fossil_range = Late Cretaceous | image = Pteronodon2.jpg | image_width = 200px | image_caption = A historical skeletal reconstruction of Pteranodon longiceps | regnum = Animalia | phylum = Chordata | classis = Sauropsida | ordo = Pterosauria | subordo = Pterodactyloidea | superfamilia = Ornithocheiroidea | familia = Pteranodontidae | genus = Pteranodon | subdivision_ranks = Species | subdivision =
* P. longiceps
* P. ingens
* P. sternbergi
Pteranodon (Greek for "wing without teeth"), from the Late Cretaceous of North America (Kansas, Alabama, Nebraska, Wyoming, South Dakota) was the second largest pterosaur genus, with a wingspan of up to 7.5 m (25 feet), exceeded in size only by Quetzalcoatlus. Unlike earlier pterosaurs such as Rhamphorhynchus and Pterodactylus, Pteranodon had toothless beaks, like modern birds.Pteranodont fossils are generally found in the Cretaceous chalk beds of Kansas. These chalk beds were deposited at the bottom of what was once an epicontinental seaway on what is now the North American continent. The Niobrara Formation is possibly the most famous unit here, and other fossils found in this formation include those of sea turtles, mosasaurs, and earlier birds (Bennett 2000).
The diet of Pteranodon is known to have included fish -- fossilized fish bones have been found in the stomach of one Pteranodon, and a fossilized fish bolus has been found between the rami of another Pteranodon. The size of Pteranodons wingspan suggests that they would have flown rather like modern-day albatrosses, gliding by navigating through thermals. This is a suggestion based on the fact that the Pteranodon had a wing disparity (ratio of wing length to hind limb length) similar to that of the albatross, with the disparity of the Pteranodon at 9:1, and that of the albatross at 8:1 (Padian 1983).
Pteranodon was notable for its skull crest. These may have been used as mating displays, or it might have acted as a rudder, or perhaps both. It has been suggested that males of the species bore larger crests, but with fossil animals it is often difficult to tell whether differences in crest shape reflect different sexes or different species.
Consensus regarding the terrestrial locomotion of Pteranodon (whether it was bipedal or quadrupedal) has historically been the subject of debate. Today, most pterosaur researchers agree that that pterosaurs were quadrupedal, thanks largely to the discovery of several pterosaur trackways. The possibility of swimming has been discussed briefly in two papers (Bennett 2001 and Bramwell & Whitfield 1974), and is currently being studied in detail at Michigan State University through the use of quantitative morphometrics and an Extant Phylogenetic Bracket (a morphologically comparative technique invented by Larry Whitmer).
A number of species of Pteranodon have been named, the most well-supported being P. longiceps, Pteranodon ingens, and P. sternbergi. Other species include, P. occidentalis, P. velox, P. umbrosus, P. harpyia, and P. comptus, though many are dubious and may be synonymous with the more well-known species. Notable authors who have discussed the various aspects of Pteranodon include Bennett, Padian, Unwin, Kellner, and Wellnhofer.
In colloquial speak, Pteranodon is often erroneously called the "Pterodactyl." However, "pterodactyl" is not actually a name of a specific species; rather, it is a term for all short-tailed toothless pterosaurs (the pterodactloidea), including the Pteranodon, Pterodactylus, and Quetzalcoatlus. This is most likely due to Pteranodons high profile in popular culture as the quintessential pterodactloid.* Pteranodon, Dino Card from Yahooligans!
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