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Viewings: 111564American paleontologists, having studied the footprints of a huge bird diatribe that lived in North America over 40 million years ago, came to the conclusion that it was not a bloodthirsty predator, how it is described in textbooks today paleontology. Claws on its feet this giant were short, dull and fragile - such impossible to keep production at eating.
Many of us from school I remember about bloodthirsty gigantic birds diatryma (first Diatryma, now Gastornis) and phororacos (Phororhacos) - the representatives of the order of the Gruiformes, which terrified the inhabitants of the Americas 56-41 million years ago. Usually draw them as a terrible predators, who, possessing a two-meter height, long legs and strong beak size with medieval axe, pursued any animal, as herbivorous and carnivorous. Indeed, the force of the blow a 50-centimeter bill was comparable to that of a falling knife of the guillotine - it could not defend even the most durable shell.
However, this view is simply the reconstruction of paleontologists, which was based on the few fragmentary finds data birds, as well as empirical conclusions. The most powerful argument was, of course, five-foot the bill. Many scientists reasoned, why herbivores essentially need a "axe", if not to kill the prey? However, even this argument, if you examine it carefully, loses its force - with this wonderful "tools" with the same success you can find delicious roots or to cut the carcasses of dead animals. That is, even with such a huge beak of diatryma could be by scavengers or vegetarians.
Its role, certainly played a more and that the first of the found skeletons of diatryma lay together with bones dwarf horses and other small mammals. Seeing this "cemetery", some paleontologists have suggested that they were victims of the terrible giant. The weakness of this version, I think, and so obvious - for example, cemeteries people many skeletons are close by, but this does not mean that during the life they hunted each other. Besides, the bodies of alleged victims could not find clear traces "" deadly bill of diatribe.
In addition, dietrim often recorded in predators because after the extinction of the dinosaurs (65 million years ago) in all ecosystems became vacant niche of large carnivores, head of the food pyramid in the communities. Among mammals have never been, who would take it, they began to appear about 43-40 million years ago when a giant birds have already started to die out. Had a very beautiful version - until mammals "delayed", the nimble bird quickly took "plum", because the evolutionary were ready to ascend to the ecosystem "throne".
And it was not particularly difficult because long legs allowed them to catch up with even the fastest production (according to the calculations, diatribe, and the modern ostriches, could run at a speed of 45-52 kilometers per hour), and high growth combined with a powerful beak - strike monstrous forces. In short, the very structure of the ancestors of the modern cranes already predisposed to the selection of prestigious "ecosystem" profession large predator. However, while diatryma had fun in the expanse of the steppe landscapes of the New world, mammals is finally able to create model" corral predator, which was several times more efficient and managed competitively all "ersatz", including birds.
In short, the hypothesis of a very beautiful and logical, but only under one condition - if to prove that diatribe really were predators. Otherwise, it falls apart like a house of cards - all of the above devices can be used for other purposes. What finally happened: while diatryma proudly paraded from the textbooks as the most dangerous predators rannakinnistu ecosystems, paleontologists have accumulated evidence that apparently, they were not.
Especially convincing version recently raised a group of paleontologists, under the leadership of George W. Masto from Western Washington University (USA). Scientists have studied the footprints left by 55,8-48,6 million years ago (the lower Eocene) some large bird in the Sandstone geological formations Takenat in the North-Western part of Washington. They concluded that the numerous and well-preserved imprints likely belong to diatryma. And, most interesting, before paleontologists finally reached the track which to judge what ate the bird.
How can it be done? Actually it's very simple - as we know, any feathered carnivore, when eats the prey or carries her to the dining venue, compresses the victim in his paws. That is why all modern heavenly robbers sharp and strong claws - otherwise hardly caught "lunch" can escape and become prey to someone else. By the way, examining claws, the scientists removed the Condor and other large vultures New and Old world accusations of predation - those were dull and fragile and consequently to keep the victim with their help absolutely impossible.
Well, what with claws was diatribe? Unfortunately, she was unable to boast of - claws on her legs were short, dull and brittle. This means only one thing - diatryma could not keep production in the legs and, therefore, was not a predator. But what, then ate this huge creature? Ate whether diatryma animal carcasses or adhered to a vegetarian diet?
George W. Masto believes that, most likely, these huge birds were still herbivorous. He drew attention to the fact that the bill of diatryma ended hook. Before, it was interpreted in favor of predation - this arrangement is useful for holding prey and tearing it up corpses. But at the same time, the beak of this type is suitable for harvesting of leaves, fruits and seeds in subtropical forests. That is why a hook-like ledge have parrots, crossbills, and seriem (Cariamidae) - extant next of kin of phororacos and dietrim who eat mostly fruits (and sometimes insects).
As for the image ferocious predator, Masto suspects that paleontologists has attributed diatreme this quality including populist motives. "Let's be honest: a terrible and fierce carnivore attracts much more attention than herbivores sissy", says the researcher. However, it should be noted that with the conclusions of the group agree far not all paleontologists - some believe that the absence of long and sharp claws is not what it says. For running the birds they could be a disadvantage because long claws hinder well dispersed. As for the way of holding of the victim, are not excluded that dietrim it could be something else.
All of this suggests that research should continue - it is possible, paleontologists will have any data, with which you will finally understand what was the way of life of this wonderful bird. However, from a study of Masto and his colleagues should make one very instructive conclusion - not every being is as it seems at first glance...
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