Bird or dinosaur?
In the 20th century, the expression “extinction of dinosaurs” was frequently encountered in scientific literature. This meant part of the Cretaceous-Paleogene extinction caused by the fall of a large meteorite on the territory of modern Mexico. But it turns out that the dinosaurs did not go extinct. Actually, not all of them died. They surround us on all continents, including Antarctica.
In recent years, paleontologists have reviewed the classification of species and concluded that modern birds also belong to dinosaurs, theropods.
Birds diverged from other bipedal dinosaurs during the Jurassic period, but due to the paucity of fossils from this period, information on their early evolutionary history is limited. Scientists specifically debate how exactly birds learn to fly: gliding from branches or running on the ground. To understand exactly what caused reptiles, the most important part of the modern ecosystem, to turn into birds, it is necessary to study their oldest species. Their closest relatives among modern birds and dinosaurs are isolated in a separate class of bird generation.
long-legged horse
Li Ming Xu of the Fujian Geological Research Institute and colleagues openedIt is probably the oldest type of aircraft. fossil-based research 148-150 million years oldIt was found near Yangyuan village in Fujian province, China. The imprint of the skeleton is well preserved in the stone, and the long legs, wings, pelvis, spine and numerous ribs are easily discernible. This is enough to reproduce the appearance of the creature with high accuracy. The open view has a name Fujianvenator genius.
It was a medium-sized bird, about the size of a wedge-tailed pheasant. His body weight was about 641 g, but judging by the skeleton, he was young and immature. The humerus is much longer (1.38 times) than the femur, which is typical for the Avials of the Cretaceous period following the Jurassic. The tibia of the tibia stands out even more strongly – twice the length of the femur and the longest among all theropods of that era. In general, the extension of the forelimbs is characteristic of all birds and distinguishes them from other dinosaurs, but the simultaneous extension of the legs is characteristic only of birds. F. prodigiosus.
Runner or swamp dweller?
Clear vision is critical to understanding the diversification of birds at the end of the Jurassic. Partially F. prodigiosus It is similar to Archeopteryx, especially in the proportions of the phalanges of the upper limbs, but differs from it in the structure of the lower body. The bird from Fujian province has almost no adaptations to a flying lifestyle, and long legs are only a sign of life on earth. This has particularly puzzled scientists because early birds, including Archeopteryx, are believed to have lived in trees. Therefore, according to the prevailing theory, they developed flying by gliding from branch to branch.
The authors of the study could not understand why the aircraft needed such hind legs. Calf extension usually increases running speed by taking longer strides.
Skeletal analysis showed that: F. prodigiosus and he can indeed be a good runner, even better than the tyrannosaurids famous for their running abilities.
But scientists are ready to accept an alternative option. Long legs are also found in swamp-dwelling birds such as storks and birds. This helps the birds rise above the water and walk in the flooded area. This version is also supported by the fact that many aquatic and semi-aquatic animal species have been found near Yangyuan before.
Like this, F. prodigiosus with equal probability he can be both an agile hunter and a pioneer of fishermen. Analysis of the toes may help clarify this issue, but unfortunately they have not been preserved.