Greg Laden found this old video of a moderated discussion between Massimo Pigliucci and Jonathan Wells [Massimo Pigliucci v Jonathan Wells on evolution and intelligent design...].
It's actually pretty good. If you don't pay close attention, you might even mistake Jonathan Wells for someone intelligent.
Thanks for posting - I hadn't seen this one. :)
ReplyDeleteSmashing video, cheers.
ReplyDelete"We also need to move a little past Darwin himself because, you know, science has this nice feature that it does evolve and progress and so, just in the same way in which modern physicists don't feel bound by what Newton said, modern biologists don't feel like Darwin is like a bible that needs to be followed, so let's talk about the modern theory of evolution..."
My emphasis.
Pigliucci hits the nail on the head. If only we can get the creationists to get past this "Darwinian" brick wall that they've adopted. I suspect not, though.
Correction...Jonathan Wells is not a biologist. He is a biology graduate. It's a big difference.
ReplyDeleteJonathan Wells got a PhD in biology from UC Berkeley by fraud pretending to be a legitimate graduate student when actually he was an agent of the Reverend Son Yung Moon of the Unification Church.
ReplyDeleteGreat video, thanks for sharing.
ReplyDeleteMassimo is a great scientist and I really like the way he talks. He is a great promoter of science. He handled Wells' stupid arguments fairly well considering the limitations of such debates.
Piggliucci does not impress me. He repeats some old selectionist myths.
ReplyDelete"Natural selection is THE ONLY mechanism that creates adaptation"
I honestly wonder if darwin would agree with that.
In any case, this phraseis repeated so oftenby neodarwinians that Piggliucci can safely rely on its "gospel value" and feel no need to explain himself further.
He should think about it, though. Piggliucci should know perfectly well, there are at least two other known mechanisms for the origin of adaptation: Phenotypic plasticity, and Exaptation.
In fact, about "the only " mechanism, it remains to be seen how important selection really is to the origin of adaptation.
What we normally observe is how selection makes a new adaptation more frequent, but not selection "creating" any new adaptation, which may rise in a single step of mutation, exaptation, or environmentally-induced phenotypic plasticity.
As Gould pointed out (but few understand) , the only way in which selection can be said to "create" adaptation is when genetic variation is copious, additive and isomorphic, so selection accumulates and concentrates genes, originating new phenotypes, similar to some cases of artificial selection.Despite being conceivable, the origin of an adaptation by selection has never been documented with true, molecular genes.
I have come to realize that many assume natural selection "creates adaptation" in a deep-time, macroevolutionary scale that is unobservable. Many take the origin of the eye, or the horse's foot, and will assume this as a process "directed" by selection, even if we were not capable of observing it in action.
These flaky, macroevolutionary notions of "creative" selection have nothing to do with the original models of population genetics, which were boldly aimed to observe selection "in action" (but, alas, has not yet been actually found in nature)
Actually, I find there is a conflation of "macroevolution" and "natural selection" that is most infuriating. In the study of almost any complex adpataion, we readily find evidence for exaptation.
A.Vargas,
ReplyDeletethis might be a stupid question from a non biologist: my understanding was that exaptation is a special case of selection.
There is something and it gets adapted by selection to do something else.
You seem to claim that this is not true.
Can you describe the difference?
Thanks.
Exaptation is NOT a special case of adaptation created by selection.
ReplyDeleteRather, there is a pre-exisiting structure, and this one acquires a new function by the same kind of happy coincidence that will allow you to keep a window open with a screwdriver
Even if you argue (or falsely assume) that the pre-existing structure originated by selection for some OTHER function (it could also originate as a non-adaptive structural spandrel) , the fact remains that it did not arise by selection for its current function, as Gould and Vrba emphasized.
So exapataion is indeed a mechanism for the origin of adaptations, but it is not an example of selection for a fucntion creating adaptation