Tiny Mongolian Dinosaur may shed “Light on the Origin of Flight”
A combined team of palaeontologists and researchers from the North Carolina State University and the North Carolina Museum of Natural Sciences have published evidence that contradicts many scientists views on how dinosaurs may have evolved into birds.
A widely accepted doctrine had been that miniaturisation was one of the last stages in the long series of changes required in order for dinosaurs to evolve into flying animals, the first avians – birds. However, the U.S. team’s analysis of a small Mongolian dinosaur, recovered from Cretaceous deposits, throws an evolutionary spanner into the works.
Throwing a Spanner at Evolution
Dr Julia Clarke, assistant professor of palaeontology at the university, led the analysis of the new dinosaur species called Mahakala omnogovae (derived from the words for Lord Shiva), which had been discovered in the Gobi desert – Mongolia. This small, basal Dromaeosaur was only seventy centimetres long and weighed little more than 2-3 kilograms. Although, the fossil is far from complete, the researchers are confident that this specimen represents an adult of the species and not a still growing juvenile, so Mahakala is one of the smallest dinosaurs known 몽고간장 대표.
Miniaturisation Leads to Powered Flight
In order to achieve powered flight, animals have to become lighter so that they are able to take off under their own muscle power. Modern birds (Neornithes) have a number of anatomical adaptations to help them fly, for example no teeth, a reduction in the number of digits, the development of a pygostyle and so on; all helpful in making their skeletons lighter and thus assisting in powered flight. It had been thought that miniaturisation would have assisted the evolution of birds, with smaller and smaller dinosaurs able to run faster and leap higher into the air; and over many generations; slowly powered flight evolved from this.
However, with Dromaeosaurs small size was relatively common well before the ability to fly evolved. There are a number of small light-weight dinosaurs known from the late Cretaceous, dinosaurs such as the one metre tall Bambiraptor from the Western United States and Byronosaurus. These swift and agile hunters show many bird-like adaptations in their skeletons. Perhaps there was a biological advantage in being small and fast running. Clearly, such small fleet-footed animals would have not been on the menu of the large Tyrannosaurs, even young Tyrannosauridae would have had little chance of catching them. There would have been plenty of food around for such animals, many small mammals, lizards, snakes, insects, even larger dinosaur’s eggs. The feathers on these small dinosaurs would have been essential for insulation, helping these animals to retain body heat.