With the discovery of a fossil snake with four legs and dating back over 100 million years, scientists now know more about the origins of this animal. Indeed, everything now suggests that this reptile would have appeared directly on the ground, and not in the sea as yet there is little thought some specialists.
The debate among scientists has long rages to determine if the snake had a terrestrial or marine origin. However, a comparative genetic study, conducted by researchers Nicolas Vidal and S. Blair Hedges in 2004, had finally shown that these reptiles are well-born on earth, that there are about 150 million years. A discovery that is now supported by the discovery, Brazil, a single fossil snake with four legs.
The new species, dubbed Tetrapodophis amplectus, resulted in a study whose results were published Thursday in the journal Science. According to the conclusions of experts, the animal was about 20 centimeters long and have lived between 146 and 100 million years ago, early in the Cretaceous era. From an anatomical and physiological point of view, many similarities with modern snakes were identified: presence of scales, flexible jaw to facilitate swallowing prey towering, elongated skull, short muzzle and crooked teeth. In addition, this reptile possessed, like his descendants constrictors, a vertebral structure to achieve extremely smooth movements to “cover” their prey.
In the end, researchers have therefore retained only one major difference from current species, namely the presence of these four members features. However, as pointed out by Dr Longrich, lead author of the study, the presence of “small palms” and “long fingers” suggest that these legs were highly specialized and they would not have been used to ensure mobility of the animal. Researchers estimate that in fact their role is rather limited to the seizure of prey or mating.
Finally, if that was not enough, the authors also noted the absence of long tail characterizes most aquatic reptiles, such as crocodiles. Additional argument which therefore calls for a terrestrial origin of snakes …
“This is the most primitive snake known to date, and it is clearly not water” , concludes Dr. Nick Longrich, relayed by the BBC.
Sources: BBC – AFP
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