Baby snake preserved in amber is unprecedented find


The first-ever discovery of an ancient snake embryo, preserved in 105-million-year-old amber, provides important new information on the evolution of modern snakes, according to a new study led by University of Alberta paleontologists.

Baby snake preserved in amber is unprecedented find
Remains of the earliest snake hatchling known to science were preserved in amber for nearly
100 million years [Credit: Ming Bai, Chinese Academy of Sciences]

“This snake is linked to ancient snakes from Argentina, Africa, India and Australia,” explained paleontologist Michael Caldwell, lead author and professor in the Department of Biological Sciences. “It is an important—and until now, missing—component of understanding snake evolution from southern continents, that is Gondwana, in the mid-Mesozoic.”

Baby snake preserved in amber is unprecedented find
The snake hatchling’s ribs and vertebrae were preserved and are clearly visible
[Credit: Lida Xing, China University of Geosciences Beijing]

Caldwell and his international team, including collaborators from Australia, China and the United States, have tracked the migration of these ancient Gondwanan snakes beginning 180 million years ago when they were carried by tectonic movements of continents and parts of continents, from Australia and India, to Madagascar and Africa, and finally to Asia, in modern-day India and Myanmar. The amber fragment in which the specimen was found also provided important clues about its environment.

Baby snake preserved in amber is unprecedented find
Researchers used X-ray micro-CT imaging to render a detailed view of the preserved postcranial skeleton
and soft tissues of X. myanmerensis [Credit: Ming Bai, Chinese Academy of Sciences] 

“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.”

Baby snake preserved in amber is unprecedented find
Along with the baby snake, researchers studied a second piece of amber with what appears to be a fragment
of shed skin from a larger snake. The degree of preservation allowed the team to model the pigmentation
pattern of the animal in life [Credit: Ryan McKellar, Royal Saskatchewan Museum]

Using CT scans, the scientific team studied the ancient snake and compared it with the young of modern snakes. Their results yielded unexpected insight into the development and embryology of the ancient specimen, including the formation of the vertebrae and notochord.

Baby snake preserved in amber is unprecedented find
Xiaophis myanmarensis snake hatchlings shown emerging from their eggs on the forest floor
100 million years ago. Gobs of tree resin foreshadow their fate [Credit Yi Liu]

“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.”

The finding is published in Science Advances.

Author: Katie Willis | Source: University of Alberta [July 19, 2018]