Paleognathus birds

lovethee History

Totally unsuspected until recently was a whole group of strange Cretaceous birds, the enantiornithiformes. Animatronic dinosaur All seem to be fairly small flying forms, and what little is known already shows great diversity in design and function. Whether they were waterloving or strongly teruestrial, or both, is an open question. In the 1970s, Jose Bonaparte found a small quarry fulI of them in latest Cretaceous sediments of Argentina. Some of the bones have unbelievably contorted and odd shapes, with toe articulations that dwindle to nothing, or arc off to the side. Alas, no complete enantiornithiforme skeletons are yet known. People’s eyes are now attuned to these bones and they are showing up all over the world. In fact, many old bird remains once assigned to modern bird groups, or already considered mysterious, are ending up in the enantiornithiformes, so much so that the group is in risk of becoming a convenient Cretaceous dumping ground for bird remains that cannot be put elsewhere. we can say that their radiation was a substantial one, and apparently occurred toward the close of the Cretaceous when the toothed birds were already in decline.

 

Paleognathus birds, which today include ostriches and the like, must have been present in the Late Cretaceous, but they have yet to be found there. walking dinosaur costume Neognathus birds are the typical modern birds. There are quite a few of their bones in the North American Late Cretaceous (mainly, but not all, near the very end of the period). originally these neognathus bones were thought to have belonged to loons, flamingos, rails, shorebirds, and cormorants, and in one case to Apatornrs, a supposed lchthyornis relative. In reality, almost all, if not all, really belonged to the shorebird group called charadriiformes, which today includes snipes, plovers, gulls, and ducks. Some of the Cretaceous forms may in fact represent the initial blossoming of ducks, with duck bills, but also with long slender necks and long wading legs. Called presbyornithiforme ducks, they lived alongside TJrrannosourus rex, and later became fantastically abundant in the early Tertiary, in which they form dense bone beds. Other neognathus birds must have been present in the Cretaceous too, and along with paleognathus birds they staged an increasingly diverse Late Cretaceous radiation.