Whence came the snake?

[Gord]

Yeah: Whence, baby?

Did snakes evolve from aquatic or terrestrial ancestors? An interesting video on the ongoing debate.

[bbvideo=560,315]https://www.youtube.com/watch?v=gIvrGtgVtr8[/bbvideo]

Youtube video from PBS Eons
Published on Feb 5, 2018

[Gawdzilla Sama]

The origin of snakes: New evolutionary scenario

Date: January 25, 2018
Source: University of Helsinki
Summary: The early evolution of snakes happened from surface-terrestrial to burrowing in the lizard-snake transition suggests a research group

The early evolution of snakes happened from surface-terrestrial to burrowing in the lizard-snake transition suggests a research group at the University of Helsinki.

The group's new findings redirect the debate on evolution towards a new underexplored evolutionary scenario. Thus, the study adds another dimension to the investigation of snake origins.

Research studies have previously established that snakes evolved from lizards. However, the transition remains amongst the most controversial topics in evolution, partly because of the lack of well-preserved fossils. Three major competing hypotheses for the habitat of early snakes -- burrowing i.e. worm-like, aquatic, or terrestrial -- have been debated for more than a century by biologists and palaeontologists.

To help clarifying this debate, researchers at the University of Helsinki compared skull shape and size, by including more than 300 species of lizards and snakes at both embryonic and adult stages.

The research group hypothesized that the early snake habitats could be predicted from the skull structure.

"The diversity in cranial structure is remarkable and appears to be tightly linked to ecological habitat modes and diet preferences in lizards and snakes," describes Associate Professor Nicolas Di-Poï from the Institute of Biotechnology, University of Helsinki.

Continues...