On July 14, 2008, Casey Luskin asks: Tiktaalik roseae: Where’s the Wrist? In this post, Luskin essentially is saying that the recent transitional fossil of Tiktaalik does not have anything resembling a wrist. The trained scientists who published the paper (Neil H. Shubin, Edward B. Daeschler and Farish A. Jenkins, Jr), the scientists that peer-reviewed their work, and countless others who have read the work disagree with him. Luskin is not a paleontologist and is in no way qualified to determine the structure/function of fossils. However, it doesn’t stop him from trying in the name of Intelligent Design.
Lets first start by defining transitional fossils. Transitional fossils are fossils that illustrate an evolutionary transition. They can be identified by their retention of certain primitive traits in comparison with their more derived relatives. In Tiktaalik for example, its “fins” have many bones and a range of movement that are characteristic of both fins and limbs, but can not really be called either. Luskin does not understand this and keeps going on about how Tiktaalik doesn’t have a wrist. This false dichotomy of either having a wrist or a fin is at the heart of Luskin’s misunderstanding.
For example, he states:
So when we come to Shubin’s technical analysis, he admits that Tiktaalik does not have not real a “wrist,” but at best he says that it has some bones that foreshadow a wrist. But does Tiktaalik’s fin really foreshadow a wrist, and how closely do its bones resemble a real wrist?”
This ambiguity between a wrist and a fin that Luskin is referring to is the exact reason that Tiktaalik is called a transitional fossil (see above). It has features of both and can’t be accurately described as either. If it was just a wrist, then the ID proponents would say it wasn’t a transitional fossil. Paleontologists would agree there. Luskin goes on to state:
In other words, the joints can flex or straighten. Shubin may be correct, but this is nothing special: the same could be said for living fish species that are capable of using their fins to prop themselves up. And they certainly don’t have wrists.
What Luskin is not understanding here is that the bones were in a configuration for propping themselves up out of water. A very big difference.
To sum it all up, Casey Luskin is not qualified to attack the credibility of Tiktaalik as a transitional fossil. He does not understand or see that this is a transitional fossil that should and does have elements that are related to both.