Discovery challenges snake origins
New fossils belonging to the ancient snake Coniophis precedens, which lived on Earth some 65-70 million years ago, hint that the slithery reptiles may have originated on land, not in the sea as previously thought.
It was from studies of the first species, called Pachyrhachis problematicus, that researchers got the idea that modern snakes might have descended from giant swimming lizards, called mosasaurs. Pachyrhachis was viewed as an intermediate step, displaying features that lay somewhere in between those of the marine creatures and today’s snakes.
The animal, which lived at the same time as the dinosaurs, probably emerged from a line of burrowing reptiles that lost their legs. The ancient reptile's small size, along with physical features of its spine, suggest that it burrowed, and analysis of its jaws shows that it fed on relatively large, soft-bodied prey.
According to the analysis by Nicholas Longrich from Yale University and colleagues, Coniophis lived in a floodplain environment and "lacks adaptations for aquatic locomotion". They describe it as a "transitional snake, combining a snake-like body and a lizard-like head".
The details of this new discovery can be found in the science journal, Nature.
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