The Discovery Institute (DI) did something out of the ordinary, well for them it's out of the ordinary. In this post from their Evolution 'news' and Views (EnV), "Genetic Similarities Between Fins and Limbs -- Evidence for Evolution, Maybe, but Not for Darwinism", Michael Denton said this:
"There never were any transitional forms making both dermal bone and endochondral bone. Organisms made one or the other.There never were any transitional forms with fin rays and digits. And I predict that no matter how extensively the fossil record is searched, the phenotypic gap between fins and limbs will remain even as the genetic gap continues to diminish. "While we could get into one of the usual arguments about how there is much more to Evolution than the work of Charles Darwin, something the DI only seems to remember when it suits them. Usually they equate all of evolutionary theory with Darwin's work as a strawman so they can try and tear away pieces.
I do have a biological question about one of Denton's statements, he said "Organisms made one or the other". That's not true is it? Granted I have to go back a number of years to a biology class, but aren't there examples of both in the human body? Let's try Wikipedia:
"A dermal bone or membrane bone is a bony structure derived from intramembranous ossification forming components of the vertebrate skeleton including much of the skull, jaws, gill covers, shoulder girdle and fin spines rays (lepidotrichia), and the shell (of tortoises and turtles)." (Wikipedia: Dermal Bone)
"Endochondral ossification is one of the two essential processes during fetal development of the mammalian skeletal system by which bone tissue is created. Unlike intramembranous ossification, which is the other process by which bone tissue is created, cartilage is present during endochondral ossification. Endochondral ossification is also an essential process during the rudimentary formation of long bones, the growth of the length of long bones, and the natural healing of bone fractures." (Wikipedia: Endrochondral Bone)That's what I thought, Denton's comment is wrong. Humans produce bones using both processes. Plus when you read the original article Denton started with, You have someone studying a subject for 20 years and then based on one article in the NY Times, Denton makes some erroneous statements, strange conclusions, and ends with a ridiculous prediction.
Even with that, what I found most interesting was this declarative statement, Denton's prediction. He says 'no matter how extensively the fossil record is searched', really? Isn't he making several assumptions? First of all, is Denton a Paleontologist?
No, he's a Biochemist with a philosophical agreement with the ID community. In fact he wrote one of the earliest books that influenced Phillip E. Johnson in his drive to form the Discovery Institute and legitimize his religious beliefs as science. That book (Evolution: A Theory in Crisis) was reviewed by actual scientists and they said that the book distorts and misrepresents evolutionary theory and contains numerous errors. So, we have a Biochemist making predictions about the fossil record. Anyone else see a problem with that?
Next issue, Denton seems to think the fossil record is a complete record. Doesn't he realize that we are making new fossil discoveries all the time? Paleontologists are still discovering, categorizing, and studying all the time. As new discoveries are made, the fossil record changes, usually becoming more complete and better defined. We discussed a good example of this back a few years ago.
Finally, the last part of his 'prediction' is his assumption that as the 'genetic gap' shrinks, and by that I believe he's saying that as we learn more and more and connect the fossil lineages closer and closer, there will never be a direct connection between limbs and fins. So . . . I have to ask this, is Denton acknowledging that Intelligent Design in nothing more than a God-of-the-Gaps argument?
OK, maybe not 'god' of the gaps, but definitely using perceived gaps to try and make an argument against current evolutionary theory, oh wait, not current evolution, but 150-year old 'Darwinism', how could I confuse the two. Denton called this a prediction, but in reality it's his opinion. He might be right, but then how many opinions and even predictions opposing Evolution have come true? Anyone else remember the "The Imminent Demise of Evolution: The Longest Running Falsehood in Creationism". If you haven't read it, you might give it a go. It's a nutshell view of the many 'predictions' made against evolutionary theory and how none of them have come true.
Back to his prediction. Since the two bone formation processes (dermal and endochondral) are two different processes that produce different types of bone, would there be an expectation of a transitional form demonstrating one type to change into the other or is it more likely that one may replace the other? I don't know what future discoveries will be (and neither does Denton), but I think what Denton's done is take two widely different things and then predict they won't intersect. What this reminds me of is a common Creationist complaint about a dog never giving birth to a cat. His 'prediction' seems to be highly improbable -- by design