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not be embarrassed by the results. The crest is so extreme in size and form that it is difficult to believe real, live creatures could have lived with such a structure, especially fliers. The Magical, Mystery Pterosaur Known from the sediments laid down in the famed Niobrara inte- rior seaway that covered what are now the great plains, Nyctosaurus and Pteranodon were entirely marine in habits so restorations Showing either Nyctosaurus gracilis soaring over the heads of tyrannosaurs are wrong, wrong, wrong. It is as absurd as showing an albatross over an elephant. Showing these pterosaurs associated with Tyrannosaurus rex is doubly inappropriate because both appear to have been extinct by the Maastrichtian. So it is equivalent to show- ing a Miocene pseudodontorn over a living elephant. The classic remains of these pterosaurs come from the sediments lain down by the famed Niobrara Written & illustrated seaway when it cut the continent in two from Texas to the Yukon. They may have soared over the oceans of the world, back when most of the deep sea consisted of the superPacific. They probably spent much of their lives in the by Gregory S. Paul air, bobbing about on the surface to rest Of perhaps feed, and returning to land only to breed. It is generally thought that the Nyctosaurus and Pteranodon were sea wave soarers in a manner similar to Just when one thinks that fossil © Gregory S Paul albatross and other long winged marine creatures cannot get any wilder or birds. As I explain in Dinosaurs of the wackier, along comes another beast of Air and elsewhere, past estimates of the ancient days that blows our neural net- mass of giant pterosaurs have tended to works. And in this case it is not even a be way understated, but even when new species. hefted up to correct values these The Late Cretaceous pterosaurs were somewhat more lightly pterosaur Nyctosaurus gracilis was loaded than marine birds. A-;nyctosaur discovered in the late l800s, at pretty weighed just a couple of pounds. much the same time and place as its Despite their very long span, albatross larger and similar relation, wings are actually rather heavily loaded Pteranodon. Long known from nearly in terms of mass/wing area because the complete skulls and skeletons, wings are so narrow and the body quite Nyctosaurus appeared to lack much in large. The flight of the lighter the way of a head crest. Although its pterosaurs must have been somewhat 6-9 ft wingspan is impressive by mod- different from that of albatross, and em standards, by late Mesozoic crite- may have been more like that of simi- ria it was dwarfed by other pterosaurs, larly lightly loaded frigate birds. But so unadorned Nyctosaurus was pretty adding to the perplexity of Nyctosaurus much neglected by paleoartists. and Pteranodon flight are the very large The situation has changed pectoralis crests on the humeri, sug- dramatically with the description by gesting they had larger, higher leverage Christopher Bennett in flight muscles than soaring birds in Palaontologische Zeitschrift of new which the crest is very reduced. specimens which, unfortunately, Perhaps the pterosaurs flapped more reside in private hands. Both fossils often than their modem counterparts. include skull and skeletal material. Even better adapted for flapping were The main body of the skull is not the, in some cases even more titanic, remarkable, being quite similar in out- nonmarine azhdarchids including line' to Pteranodon except that the Quetzalcoatlus, in which the wings very slender upper and lower beak tips were relatively shorter and much more matched one another in length, unlike robustly constructed even in smaller the other pterosaur whose upper beak examples. strongly overbit the lower. One of the Bennett notes critical points about new Nyctosaurus skulls is pretty much nyctosaur crests in regards to their pos- completely preserved, including hap- sible impact on flight. First, their Cl1SP pily the entire crest. In the other spec- edges differ from the amorphous rims imen the crest is shattered and frag- of the crests of pterosaurs in which ker- mentary but what is present shows similar form. The crest consists of a atin sheaths greatly expand the area of the crest. So in life the crest proba- swept back, transversely flattened, very narrow strap that is about two and bly looked pretty much like what we see in the fossils, being reminiscent of a half times longer than the skull proper. There is a slight taper progressing flattened deer antlers. If so, then the crest would have had minimal rudder up the crest. Shortly up the crest is a branch directed backwards, about the effect for something of its great dimensions. Second, there are specimens same length as the skull, and similar in width and breadth to the main branch about as big as the crested skeletons that lack large crests. That the crestless wi th a slight distal taper. specimens are consistently immature in their bone structure indicates that The crest is a psychedelic structure that gives new meaning to the the crests did not appear until final maturity. It is less likely that the crest- neocreationist concept of "intelligent" design -- it looks like someone less specimens were the girls and the crested ones the boys, although this designed it while on LSD, A cross between a reindeer and a flying archosaur cannot be ruled out until more specimens are sampled. If remains quite pos- is suggested. Only bioevolution could come up with something like this and sible that, as in Pteranodon, the crests of females were much smaller than 46 Prehistoric Times No, 62 • OCT/NOV 2003 - those of the males. rather like the tails of peacocks. The bigger and better formed the crest the The combination of low surface area and failure to appear until all better, being evidence of the health and fitness of the male. The crests could grown up suggest that the crests were not airfoils such as rudders, but were have been a solid colored or banded, dark, light or both. Brilliant colors are instead display features. In this case a primary objective of the crests would a real possibility. What motions the crest may have been put through are be to have minimal impact upon the aerodynamics of their owners, achieved uncertain, vertical and/or broadside presentations are possible. The promi- by being extremely thin from side to side. They probably barely disturbed nent beaks may also have been part of the display, both visually and as a the air as they cut .through it like a hot razor through creamy butter. means to an auditory component via clattering. Suggestions that the crests were broad surfaced thrust generating sails (as The Nyctosaurus scene shows a crowded, guano contaminated when a wind vessel sails into the wind using the sail to generate lateral lift rookery, atop a cliff on a Niobrara island. It is the beginning of the breeding as the wind blows along its surface) are not viable because, aside from the season, and in the forefront a full crested male and female are displaying to lack of anatomical evidence, sails only work when the mainbody of the ves- one another in a selection and bonding ritual that another male is approach- sel has a substrate that it can work against. Water in the case of sail boats ing to try his luck. Other Nyctosaurus rest as still others soar on the cliff and ships, the ground or ice in case of sail????? [what are terms for sail dri- induced updraft, and more fly to and from sea amidst small marine birds. ven ice runners and land racers"], Also, when sailing against the wind the Large marine birds are often mate loyal over long periods of time; we have sail is set at an angle to the ..------------------------------------, no idea if this was true of their direction of travel, so a © Gregory S Paul pterosaurian counterparts. Big pterosaur that tried to do this marine birds tend to have long with its crest would also have lifespans so they breed slowly. to swivel its large beak to the \ . The same may have been true side, creating a rudder effect \ . of oceanic pterosaurs. Marine that would prevent the crea- fliers are not well suited 'for ture from moving in a gathering much in the way of straight line. nesting materials, which may One known not be available on barren pterosaur .exhibits the knife islands anyway. like lower beak needed to After pterosaur eggs surface skim for food like were deposited they could not skimmers, but the Niobrara be left exposed to the ele- pterosaurs lacked this hydro- ments, so the eggs were proba- dynamic feature. Because bly incubated. Adult Pteranodon's upper beak was pterosaurs probably had the longer than the other, Bennett high metabolic rates needed to suggests it could not feed on warm eggs. Heat transfer the wing, and instead did so could have been via a naked while. floating as do some brooding patch on the chest, as marine birds such as alba- sometimes practiced by birds. tross. Surface feeders would Presumably the chicks were seem vulnerable to swim- fed for a period by one or more ming predators, perhaps the ~......,=;;.;.;...."""'==-"'--.;;..;;..=== parents. The variable size of later prefer to focus on fat and oil laden fish and cephalopods rather than specimens found far out into marine sediments suggest that the pterosaurs skin and bones fliers during joint feeding frenzies. Nyctosaurus may have left the nest and became active fliers before completing growth, a major dif- surface fed, or dipped into the water while flying like gulls, or both.

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