A paleontology study from Yale University reveals snake family tree and anatomically distinctive characteristics of the ancestral snake.
Until recently it was believed that the sinuous creatures developed in watery habitats and didn’t look much different from what we know today. The Yale University study, conducted by Paleontology Dr. Allison Hsiang, begs to differ.
It is understandable why there was a significant gap in understanding the evolutionary tree of snakes. Their skeletons are quite fragile and don’t resist sufficiently to resurface as fossils so valuable in understanding evolution.
Now, analyzing modern snake anatomy in connection with information from the fossil record and snake genomes, the study revealed that in fact, the first snakes evolved on land. They roamed their territories making use of tiny back limbs that featured ankles and toes.
Most likely the protosnake originated in the forests of the Southern Hemisphere 128 million years ago. The continent of Laurasia was their place of origin. The continent was roughly the size of Europe, Asia and North America combined.
“By analyzing the genes, fossils and anatomy of 73 different snake and lizard species, both living and extinct, we have managed to generate the first comprehensive reconstruction of what the ancestral snake was like,”
stated lead researcher Allison Hsiang.
In stark contract with the majority of ancestral reptiles which are believed to have been diurnal, the ancestral snake might have in fact been a nocturnal predator. Paleontologists think that the point of emergence of ancestral snakes is placed in the early Cretaceous, at the same time with the emergence of a variety of mammals and birds.
Predator as it was, the protosnake provided researchers with a surprise. It didn’t feature the constriction ability that present day snakes have, such as boa constrictors. Thus, the predator could feed on anything as long as it didn’t overpass the size of its head.
These forest dwellers presented needle-like hooked teeth that helped with killing prey and feeding.
The nocturnal habit slowly disappeared with the ancestral snakes, making way for the return of diurnal habits approximately 50-45 million years ago. The first family of snakes that is believed to have been diurnal is Colubroidea, out of which 85 percent of living snake species stemmed.
The study conducted by the team from Yale University was published in the journal Evolutionary Biology and helped shed light on the evolutionary tree of snakes, a theme that has long puzzled the scientific community.
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