One of the most strange and even extravagant hypotheses of recent times is the opinion that the famous meteorite, which killed all the dinosaurs of the planet for 65 million years, never really existed. Instead of dying together during a nuclear winter, dinosaurs could simply gradually evolve into birds. But how exactly did the giant reptiles suddenly shrink in size, overgrown with feathers, and why did they do it? It seems that scientists from Australia were able to find answers to all these questions and even partially prove the veracity of an unusual theory.
Ancestors of modern birds
Scientists have known for a long time that birds are the distant descendants of dinosaurs. However, how exactly evolutionary transformations took place, the researchers managed to find out only thanks to a detailed analysis of fossil theropods – two-legged predatory dinosaurs. It turns out that these clumsy lizards really at first somehow managed to noticeably decrease in size during evolution, and then completely turn into representatives of the bird family that we are familiar with.
Mike Lee, the lead author of this study at the South Australian Museum in Adelaide, argues that the transformation of formidable predators into birds was very complex and consisted of several important stages. It is no wonder: the weight of these 200-kilogram dinosaurs, which inhabited our planet several hundred million years ago, gradually decreased to only 800 grams, according to nature.com magazine.
How exactly did the giant monsters , armed with razor-sharp teeth, manage to shrink so much? There is an opinion that, most likely, the process of decreasing in size took place continuously, and each next descendant of the future proto-bird gradually turned out to be less and less in size compared to its ancestor.
To test the theory put forward, Lee and his colleagues tracked evolutionary changes in 120 theropods around the world, thus discovering 1,549 distinctive features in their skeletons. It turned out that the transformations studied by Australian researchers took place over 50 million years: this is how much time it took for the lizards to gradually decrease in size and become overgrown with feathers, and during each of these time periods, the animals acquired other characteristic features. As a result of all the changes, new anatomical features allowed the protobirds to occupy those niches of survival in nature that were previously completely inaccessible to their large ancestors. So, having discovered in themselves the ability to fly, glide and jump, the former Allosaurus,
Although the representatives of the former theropods lost more and more in size and mass with each generation, their skulls still remained large enough in relation to the body, which may indicate the presence of a large brain in the ancient protobirds, which allowed these organisms to populate most of the surface of our planet and survive. when 65 million years ago the Earth faced a mass extinction .
Undoubtedly, the unusual theory of Australian scientists still needs to be tested, however, who knows: maybe every morning we have breakfast with you not just scrambled eggs, but we eat the most real descendant of an ancient creature that once instilled fear in everyone the rest of the animals of our blue planet – tyrannosaurus.