Why dinosaurs well developed feathers on all four limbs? This question arose before the scientists in 2003, with the discovery in the North-East of China remains species Microraptor gui, who lived approximately 130 million years ago. On the first reconstruction of this dinosaur was a picture floating in the air with outstretched limbs. Further feathers hind limbs "cleaned up", and microraptor was to remind biplane Wright brothers. But this variant has been heavily criticized.

A simpler solution offers Justin Hall of the University of South Carolina (USA). In his opinion, soaring dinosaur could hold back legs drawed in, until it became necessary to turn to, for example, to evade branches or to attack prey. If a little to throw the right foot during a deflection to the left (the reverse is also true), and thus can significantly depending on the angle of the leg) to decrease the radius of the turn.

With aerodynamic point of view, says Mr. Hall, it has more sense than the constant pulling both rear legs. The fact that the form (of course, hypothetical) array of feathers hind limbs little lift, so additional surface is worse than useless for rectilinear motion. "The more the surface, the greater the resistance of the air," - like co-author Michael Habib.

On the contrary, additional flexibility would not hinder microraptor, the more so in shape, he is still a little different from the serpents of the dust brothers.

M. gui is the most famous of the four-winged dinosaur, but not the only, and created in this study, the method of calculation of additional maneuverability will be useful in other cases, believes another co-author, Luis Chiappe from the natural history Museum of Los Angeles County (USA). And dexterity, underlines Mr. Habib, everyone needs, regardless of whether they were on a steady flight or just soared.

The results of the study were presented at a conference of the Society of vertebrate paleontology.

Based on the materials ScienceNews.