We found this news at the website of the European Synchrotron Radiation Facility (ESRF), a consortium of more than a dozen countries operating a synchrotron in Grenoble. The article we’re going to discuss is X-rays reveal hidden leg of an ancient snake. Here are some excerpts, with bold added by us:
A novel X-ray imaging technology is helping scientists to better understand how in the course of evolution snakes have lost their legs. The researchers hope that the new data will help to resolve a heated debate about the origin of snakes: whether they evolved from a terrestrial lizard or from one that lived in the oceans. New, detailed 3-D images reveal that the internal architecture of an ancient snake’s leg bones strongly resembles those of modern terrestrial lizard legs. The results are published in the 8 February issue of the Journal of Vertebrate Paleontology.
We looked, but we can’t find a link to that paper, so let’s read on:
Only three specimens exist of fossilised snakes with preserved leg bones. Eupodophis descouensi, the ancient snake studied in this experiment, was discovered ten years ago in 95-million-year-old rocks in Lebanon. About 50 cm long overall, it exhibits a small leg, about 2 cm long, attached to the animal’s pelvis. This fossil is key to understanding the evolution of snakes, as it represents an intermediate evolutionary stage when ancient snakes had not yet completely lost the legs they inherited from earlier lizards. Although the fossil exhibits just one leg on its surface, a second leg was thought to be concealed in the stone, and indeed this leg was revealed in full detail thanks to synchrotron X-rays.
Here’s a brief Wikipedia article on that fossil: Eupodophis. Amazingly, it’s already been updated to reflect what we’re writing about today. We continue with the ESRF article:
The high-resolution 3-D images, in particular the fine details of the buried small leg, suggest that this species lost its legs because they grew more slowly, or for a shorter period of time. The data also reveal that the hidden leg is bent at the knee and has four ankle bones but no foot or toe bones.
“The revelation of the inner structure of Eupodophis hind limbs enables us to investigate the process of limb regression in snake evolution,” says Alexandra Houssaye [of the Museum National d’Histoire Naturelle, who led the research team].
There’s more detail at the article we’re quoting from. Oh, you may be wondering why this news comes from ESRF. That’s explained by this excerpt:
“Synchrotrons, these enormous machines, allow us to see microscopic details in fossils invisible to any other techniques without damage to such invaluable specimens,” says Paul Tafforeau of the ESRF, a co-author of the study.
So there you are. Now you have two competing theories about the origin of snakes: One, that snakes evolved from lizards, and transitional fossils exist as evidence; or two, that snakes lost their legs in a Ka-boom! event in the Garden of Eden after one of them tricked Eve into eating the forbidden fruit. You decide, dear reader.
Update: See Creationists Explain Lizard-to-Snake Fossil.
See also: How Did the Snake Lose Its Legs?
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