Snake ancestors had legs, cheekbones 100 million yrs ago
TORONTO: Snake ancestors that lived nearly 100 million years ago had legs and a cheekbone which disappeared entirely in their modern day descendants, according to a study which examined fossils of an ancient rear-limbed reptile called Najash rionegrina.
The study, published in the journal Science Advances, showed that snakes possessed hind legs during the first 70 million years of their evolution, and had cheekbones -also known as a jugal bone. The researchers, including those from the University of Alberta in Canada, also revealed how the flexible skull of the ancient snake evolved from their lizard ancestors.
Until now, understanding of the evolutionary history of early snakes was limited by unavailability of fossil records, they said. The nearly 100 million-year-old fossil snakes were found in Northern Patagonia , they added.
“Najash has the most complete, three-dimensionally preserved skull of any ancient snake, and this is providing an amazing amount of new information on how the head of snakes evolved. It has some, but not all of the flexible joints found in the skull of modern snakes,” said study co-author Alessandro Palci from Flinders University in Australia.
The researchers performed high-resolution scanning and light microscopy of the preserved skulls of Najash, revealing new anatomical data on the early evolution of snakes. According to the study, Najash are closely related to an ancient lineage of snakes that populated the southern hemisphere of one of the Earth’s earliest continents Gondwana, and may be related to only a small number of modern snakes. AFP