This one ought to get the creationists excited. It’s from PhysOrg: A ‘transitional fossil’ debunked. A debunked transitional? Wowie — there must be celebrations in Seattle and wherever it is in the Kentucky wilderness that ol’ Hambo has his headquarters. Here are some excerpts, with bold font added by us for emphasis:
The origin of snakes from lizard-like precursors with paired limbs has long been a controversial subject. This reflects the lack of fossils and conflicting results from phylogenetic assessments using molecules and anatomy, respectively. Thus a 2015 report announcing discovery of a 110-million-year-old skeleton of a snake-like reptile from the Cretaceous of Brazil generated worldwide interest.
We remember that announcement. We wrote about it in How Did the Snake Lose Its Legs?
Then they say:
The subject of the 2015 report is an articulated 20 cm long skeleton of a snake-like reptile from the Cretaceous of Brazil. Named Tetrapodophis (“four-footed snake”), this fossil has a long body with some 160 vertebrae in front of the tail but also four very small limbs. Such a combination of features had never been observed in any lizard or snake. Tetrapodophis purportedly showed that body elongation preceded loss of limbs in the evolution of snakes and thus gained international attention as a “transitional fossil.”
Yes, we described all that in our earlier post. Let’s get to the debunking. PhysOrg tells us:
Recently a team of researchers led by Michael W. Caldwell (University of Alberta) has carefully re-examined the only known fossil of Tetrapodophis. They found that this reptile lacks many key features of snakes in its skull and vertebral column.
Well, it’s a transitional species. Isn’t that expected? PhysOrg continues:
Instead its long skull has large eye sockets and its teeth are not recurved, unlike those of snakes. Caldwell and his colleagues also observed that the limbs of the Brazilian specimen share traits with those of a number of water-dwelling reptiles. They concluded that Tetrapodophis probably used its long body for eel-like swimming or crawling.
Caldwell thinks the fossil isn’t very snake-like at all. There’s only one paragraph left. The debunking is probably there. Here it comes:
Caldwell concludes: “This specimen challenges a number of long held ideas about the evolution of elongation and limb reduction in tetrapods — it displays anatomical features that seem to break all the rules. To make it more complicated, the skull is poorly preserved and the animal is extremely small, thus making it hard to pinpoint morphological features linking it to any one particular group of squamates [the group comprising lizards and snakes]. It is a perfect paleontological storm in every way.“
That’s it? That’s the debunking? One man questions a fossil’s significance and that means it’s “debunked”? That’s undoubtedly how the creationists will interpret this. And even if Tetrapodophis is ultimately found not to be the transitional fossil it’s been thought to be, that certainly doesn’t mean that snakes with limbs existed only briefly in the Garden of Eden, and then lost their legs because of Adam & Eve. But that’s how creationists will react to this news.
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