How Have CT Scans helped Us Understand The Evolution Of Snakes?
Computerized Thomography (CT) uses X-rays in order to produce detailed images of the inside of a body. Many images are taken along 360 degrees and put together to obtain a final 3D model. This technique allows an image to be created without having to invade the body. This is very useful when analyzing fossils since they can't be opened or manipulated.
A 90 million year old fossil is giving scientist new indications on when snakes may have evolved to loose their limbs. Previous suggestions stated that snakes lost their limbs when they migrated to the sea to become aquatic animals. Using CT scans, an 3D model of the inner ear of the fossilized specie, the Dinilysia patagonica a close relative to the modern snake, was made. The model of the skull showed a similar structure to those of snakes who currently burrow.
This therefore suggests that snakes started evolving on land and not in the sea. Due to this newly found fossil, geoscientist at the University of Edinburgh believe that snakes lost their limbs when they migrated to burrows in order to be more mobile to hunt in this environment.
I find that this hypothesis is quite interesting and unexpected. On a first thought, it wouldn't have occurred to me that a structure such as the interior structure of the ear of an organism would give us information on the evolution of the limbs of that same specie. Therefore I was pleasantly surprised by this idea.
Bibliography:
1.http://www.wired.co.uk/news/archive/2015-11/27/how-snakes-lost-their-legs
2.https://www.sciencedaily.com/releases/2015/11/151127195113.htm
3.http://www.amnh.org/explore/news-blogs/research-posts/reptile-fossil-solves-mystery-of-how-snakes-lost-their-legs/
4.http://www.nhs.uk/Conditions/CT-scan/Pages/Introduction.aspx
1.http://www.wired.co.uk/news/archive/2015-11/27/how-snakes-lost-their-legs
2.https://www.sciencedaily.com/releases/2015/11/151127195113.htm
3.http://www.amnh.org/explore/news-blogs/research-posts/reptile-fossil-solves-mystery-of-how-snakes-lost-their-legs/
4.http://www.nhs.uk/Conditions/CT-scan/Pages/Introduction.aspx