Gobipteryx

Gobipteryx (from Gobi , Greek pteron “wing”) is a genus of prehistoric bird from the Campanian Age of the Late Cretaceous Period. It is not known to have any direct descendants. Like the rest of the enantiornithes clade, Gobipteryx is thought to have gone extinct near the end of the Cretaceous. Based on a skull length of 45 millimeters, Gobipteryx has been estimated to be approximately the size of a partridge. Its bones are fibrolamellar. The skull’s general shape is gradually tapering toward the front. Gobipteryx has a toothless beak formed from the fusion of the premaxillae bones. The skull is characterized as being rhynchokinetic with the pterygoid bones articulating with both the vomers and the palatine. The nares are tear shaped and the choana is located below them, more rosteral than in most modern birds. The nares are smaller than the antorbital fenestrae, a primitive feature for ornithurae birds. In addition, Gobipteryx's skull has an articulated rostrum. The jaw hinge is associated with the articulation of the quadrate with the pterygoid processes. The articular region of the mandible contains internal and retroarticular processes and has uniform symphysis. This animal has a large, uniform, and sutureless braincase. The vertebral column consists of at least 19 presacral vertebrae, the last 6 of these being dorsals. The neural spines of the twelfth and thirteenth vertebrae form the nuchal blade, which represents the point of greatest elevation in the vertebral column. The scapula contains a prominent glenoid labrum and tapers backward, ending as thin rods. The coracoids are slightly concave anteriorly and are separate from the scapulae dorsally. They also stick out from the neck on either side. Gobipteryx's clavicles curve in a way that is consistent with that of other birds. The humerus is posteriorly convex (a normal trait for birds) and the head is comma-shaped. Gobipteryx's ulna is about twice as thick as the radius. Metacarpals II and III have been found in embryonic fossils and are observed to be about equal size and are in close contact with each other. Gobipteryx is believed to have been capable of flight. The scapula is long, and therefore, well suited for flight by having more area for muscle attachment. In addition, the forelimb of Gobipteryx is more than twice the length of the thorax, falling within the acceptable range observed in flying birds. Gobipteryx, along with other enantiornithes, is thought to have superprecocial development, in which it was capable of flying upon hatching. Evidence for this comes from the fact that the forelimbs and shoulders of advanced embryos are almost completely ossified. In addition, the growth of G. minuta has been shown to slow down immediately following hatching. This suggests that it was highly mobile in its life, since locomotion has been shown to slow the growth of young birds by focusing energy and resources elsewhere. This onset of flight so early in life is not seen in most modern birds, which begin flying when they have reached or are close to full size.