RSS feeds in the directory: 2798
Added today: 0
Added yesterday: 0
The Study of the fossilized remains of a bird that lived approximately 75 million years ago on the territory of the U.S. state of Utah, showed that she had adaptations to flight similar to those that exist in modern birds, and hence for flight characteristics it is not inferior to the current birds.
the Ancient form, called Mirarce eatoni, belonged to the group of enantiornithes (Enantiornithes), arose independently from ancestors of modern birds. Enantiornithes were widespread in the Cretaceous period. Their skeleton differed from modern birds in several parts, for example, they had teeth and claws on the wings.
enantiornithes Disappeared about 66 million years ago simultaneously with the dinosaurs.
you Know more than 80 species of enantiornithes in size from a Sparrow to a vulture, however, some of these species are described only on one dice. The most representative finds of enantiornithes was made in the formation of Las Ojas the Spanish city of Cuenca, in the Chinese province of Liaoning (biota Rehe), generally finds these birds are known on all continents except Antarctica. Also known finds eggs of enantiornithes.
the way of life among enantiornithes groups were used, similar groups of modern birds. Some of them were swimming and eating algae like a modern duck, others were granivorous, like sparrows, and others were catching insects like swallows, the fourth preferred fish with the cormorants, the fifth were predators, like falcons and sixth produce their own food in the surf zone, like modern waders. In late Cretaceous deposits in Romania discovered evidence of the existence of enantiornithes breeding colonies, where they, like modern weed chickens, laid eggs in the pile of crop residues, serving as natural incubators.
But here the flight of enantiornithes still is the subject of debate among scientists. They obviously knew how to fly, but the differences in the structure of the skeleton is forced to think that their flight was different from flight of modern birds. Sometimes I suppose that they flew worse. The fragmentary nature of the extant skeletons of many enantiornithes does not resolve this question definitively.
the fossilized remains of Mirarce eatoni, was found in 1992 in a geological formation Kaiparowits (Kaiparowits Formation) within the reserve Grand Staircase-Escalante, paleontologists are lucky. Her skeleton was the most complete skeleton of enantiornithes in North America, missing only the head.
who Described the ancient bird scientists say whether it had the keel of the sternum, serving as the modern birds, for attachment of powerful muscles, lowering the wings. Of particular interest are the primaries bumps – special outgrowths on the ulnar bones, the employees have the current birds for fastening of feathers. Earlier this anatomical details on the remains of enantiornithes. The presence of tubercles and a swing keel of the sternum shows that enantiornithes independently had the same aerodynamic fixtures, and modern birds.
the Description of enantiornithes of Utah published in the electronic scientific journal PeerJ.
Residents of calgary refused to accept the Olympic games 2026 14.11.2018 at 09:26
The Kremlin said the fine The New Times 14.11.2018 at 09:02
Kozhemyako as a contender 14.11.2018 at 09:00
Peskov declined to predict new US sanctions 14.11.2018 at 08:46
Became known, the unusual structure of the crystalline modification of nitrogen 14.11.2018 at 08:21
The Muscovites were not ready to send Sobyanin presidents 14.11.2018 at 08:09
The Volgograd student brought to class an ax and gasoline 14.11.2018 at 07:24