Paleontologists have discovered dinosaur has a beak

© Photo : John ConwayПтица-tinamou (bottom) and dinosaur-anchiornis (top)Paleontologists have discovered dinosaur has a beak© Photo : John Conway

Scientists found in Eastern China, an unusual dinosaur, to uncover the story of the appearance of the beak of these ancient reptiles and the ancestors of birds, according to a paper published in the journal PNAS.

«In the history of the planet dinosaurs and their relatives lost teeth and gained a beak or similar structure at least seven times. We know how to form the beak of modern birds, however, there is no generally accepted ideas on how they could acquire them in the course of evolution», says Xu Xin (Xing Xu) from the Institute of vertebrate paleontology KAN in Beijing.

The reason for the disagreement among scientists is that it is not clear why dinosaurs, especially relatives of birds and small predators, needed a beak. The part of paleontologists believed that the bill appeared for dietary reasons – he helped the lizards and the future birds it is better to grind solid food, and stabilized their skull while trying to capture the prey. Other scientists disagree with this point of view and believe that the bill appeared to facilitate weight and body adaptations to flight.

Why scientists are unable to understand which of these theories is correct? The fact that over the last 20 years, they could not find any «transitional» fossils that would have been an analogue of the beak, and vestigial teeth. Moreover, genetic experiments to create «kurisutaru» show that the ancestors of modern birds lost teeth and gained a beak at the same time, which further complicates the disclosure of the secret of its appearance.

Xu and his colleagues approached the answer to this question, comparing the body of an ancient bird-kupeornis (Sapeornis), found in Eastern China recently, and several bipedal dinosaur of oviraptor, possessing a powerful beak and lived on the territory of the PRC and Uzbekistan.

Through this analysis, the researchers drew attention to the unusual structure of the jaw of operator kind Caenagnathasia whose remains were found in the Kyzyl Kum desert about 20 years ago. This creature is one of the small oviraptorid in Earth’s history and are today considered to be the ancestor of some of the most bizarre dinosaurs such as the four-meter-long «chicken from hell», Anzu wyliei.

Educate them with the help of MRI, scientists have discovered at the base of the beak of this lizard special grooves and holes, inside of which formed rudimentary teeth. Having made this discovery, the scientists checked whether any «holes» in the jaws of supernice. It turned out that they are present in the beak of an ancient bird that pointed to a possible mechanism for the loss of teeth the ancestors of birds and «cleworth» dinosaurs.

Scientists believe that the ancestors of birds, and the lizards got rid of the teeth is not right – originally they had young individuals who they then gradually fell out as they Mature and transition to the new diet. An example of this could be the dinosaur, Limusaurus inextricabilis, which had a similar «baby teeth» in my childhood, the remains of which Xu and his colleagues found last year.

Subsequently, his teeth began to disappear even before the birth of Chicks and calves, and all this, say scientists, indicates that birds and lizards have lost teeth and gained a beak for gastronomic reasons for the transition to a new diet and new ecological niches. The gradual abandonment of the teeth helped them survive this transition and adapt to a new life.

Interestingly, the «progenitor» of the beak can be horn special tooth that the baby dinosaurs and modern birds, the Chicks use to get out of the egg at the time of his birth. When dinosaurs and the birds began to lose teeth, this tooth began to grow, eventually becoming a beak, and other Horny structures are characteristic of modern birds and the dinosaurs of the Earth.