The world's first known ancient snake embryo has been discovered in Myanmar preserved in 99 million years old amber. Now, a new study published in Science Advances and led by University of Alberta paleontologists examines what the fossil can reveal about the evolution of snakes.
The first of its kind in the world
"We present the first known fossilized snake embryo/neonate preserved in early Late Cretaceous (Early Cenomanian) amber from Myanmar, which at the time, was an island arc including terranes from Austral Gondwana," states the paper's introduction. The study's team used CT scans to analyze the remains and compare them with the infants of modern snakes.
Their research revealed that the tiny critter, about 5 centimeters long, is a new species named Xiaophis myanmarensis. The fossil skeleton is missing its skull which leads the researchers to estimate that in total it could not have been more than 8 centimeters.
What is truly impressive about the discovery, however, is what the tiny fossil indicates about the trapped animal's heritage.
“This snake is linked to ancient snakes from Argentina, Africa, India and Australia."
“This snake is linked to ancient snakes from Argentina, Africa, India and Australia," explained the study's lead author paleontologist University of Alberta Michael Caldwell in his institution's online magazine Folio.
"It is an important—and until now, missing—component of understanding snake evolution from southern continents, that is Gondwana, in the mid-Mesozoic," continued Caldwell. Researchers have struggled with analyzing fossil records for snakes as very few have ever been uncovered.
The critters' fragile constitution does not allow them to preserve well and baby species are even more delicate. This new fossil brings much-needed information to Caldwell's team who has been tracking the migration of ancient Gondwanans, that started over 180 million years ago and saw the species navigate from Australia to Myanmar.
First evidence of a fossil snake living in a forest
Furthermore, the amber fragment the snake was found in was also useful to the scientists. “It is clear that this little snake was living in a forested environment with numerous insects and plants, as these are preserved in the clast,” explained Caldwell.
“Not only do we have the first baby snake, we also have the first definitive evidence of a fossil snake living in a forest," added the paleontologist. Most previous snake fossils have not contained enough evidence to determine the animal’s habitat.
The research saw the collaboration of and international team that included the China University of Geosciences, the Institute of Zoology at the Chinese Academy of Sciences, Midwestern University, the South Australian Museum, Flinders University, the Royal Saskatchewan Museum, the University of Regina, the Paleo-Dairy Museum of Natural History and the Beijing Forestry University. The fossil's discovery was well-received by paleontology teams worldwide as a key breakthrough in the study of ancient snakes.
“All of these data refine our understanding of early snake evolution, as 100-million year-old snakes are known from only 20 or so relatively complete fossil snake species,” said Caldwell. “There is a great deal of new information preserved in this new fossilized baby snake.”