FOSSILS TRAPPED IN AMBER OFFER CLUES TO THE ORIGINS OF SNAKES
In 2016, Lida Xing was combing the amber markets of Myanmar when a merchant enticed him over to his booth with what he said was the skin of a crocodile trapped in amber. When Xing inspected the specimen and noticed the diamond-shaped pattern of its scales, he realized what he was holding was actually a 99-million-year-old snakeskin.
Xing, who is a paleontologist from the China University of Geosciences in Beijing, said that of the hundreds of thousands of amber pieces discovered in the area, no one had ever before found a snake.
He purchased the snakeskin and set up a meeting with Michael Caldwell, a snake paleontologist at the University of Alberta. A few minutes before Xing boarded his flight to Canada, a different colleague alerted him to another recently discovered snake specimen that was more amazing than the first: Entombed in a silver-dollar-size chunk of amber was a baby snake.
“The fossil is the first baby snake and the oldest baby snake to yet be found,” said Xing. Before this finding, paleontologists had not uncovered a fossilized baby snake even in the rock fossil record, said Caldwell.
Xing and Caldwell reported their findings from the two specimens recently in the journal Science Advances. The work provides insight into the evolution of snakes, their early-stage anatomical development and their prehistoric spread across the globe.
Only the bottom half of the baby snake’s sinuous body was preserved in the amber, which is fossilized tree resin. Because the skull was missing, the people who found the fossil thought the tiny creature inside was either a centipede or millipede.
Through the use of a micro-CT scanner and a synchrotron, scientists confirmed that the specimen was a baby snake, a new species they named Xiaophis myanmarensis. It resembles existing species of pipe and grass snakes.
Scientists are not sure where snakes originated from and how they spread throughout the world. The new specimens offer clues for one potential pathway for their prehistoric movement around the planet, said Ryan McKellar, a paleontologist from the Royal Saskatchewan Museum in Canada and an author on the paper.