Until now it was thought thatstrange way of walking “crouched” of some dinosaurs and current birdsit was his way of keeping his balance after the large reptile’s tails got progressively shorter. Buta study with 3D modelsled by scientists from the Royal Veterinary College, London (UK) and published in the latest issue ofNaturecontradicts this hypothesis, and states thatthe way of moving changed due to the lengthening of the legs.
As echoed by the SINC agency, the legs of animals such as Velociraptors were lengthened for hunting or climbing. Ythe gradual growth of the legs of the bipedal dinosaurs caused them to advance their center of gravityand forced them to adopt the squatting posture typical of their descendants the birds, with the femur practically in a horizontal position.
To understand how these dinosaurs’ gait evolved, scientists created a 3D model from the skeleton of 17 archosaur reptiles, both current – crocodiles and birds – and extinct – Microraptor and Archeopteryx. The next step was to add “meat” and muscles to this model virtually, based on data obtained by computerized topography scanners of its living relatives. According to Vivian Allen, co-author of the work, “it was like wrapping the skeleton in wrapping paper, which is then ‘inflated’ to make it more real.” In this way, an estimate of the shape and size of these animals could be obtained.
As Allen acknowledges, the great surprise of the study was that it did not find a relationship between the tail reduction and the change in balance. “We checked it many times with various methods, it was even difficult for us to accept thatthe tail hypothesis was not correct”, He assures. What had changed the center of gravity was that the legs of the reptiles grew, especially in species like Velociraptor and the most primitive bird, Archeopteryx. According to his colleague John R. Hutchinson, the most striking thing about the project has been that it has been able to “reconstruct the evolution of all body dimensions of extinct animals in a quantitative way for the first time.” And now anyone can repeat his technique, since, as the researcher states, “they have shared the main methods and 3D images of the study so that other scientists can use them.” “Dinosaur fans and scientists will win,” he concludes.
