Until now I haven't found many creationist sites that respond to talk.origins directly. Most seem to tread the Behe/Dembski party line of "information theory disproves evolution" or parrot the old, tired arguments that even Answers in Genesis is wary of (moon dust, helium, the strength of Earth's magnetic field, etc.). On a forum that I frequently attend, however, someone posted a link to a site - or rather, a subsection of a site - that takes on talk.origins directly.
http://www.alternativescience.com/faq_or_fiction.htm
The site is maintained by Richard Milton, author of such books as The Facts of Life and Shattering the Myths of Darwinism, who appears on the talk.origins site in a debate over the hominid fossil record. Mr. Milton purports to set straight "a few of the more gross errors of scientific fact" in the talk.origins FAQ archive in a series of four pages: a response to the Observed Instances of Speciation FAQ, another to the Transitional Vertebrate Fossils FAQ, a third to Kathleen Hunt's account of equine evolution, and finally, a discussion of whether the development of antibiotic resistance among modern disease-causing organisms can be considered "Darwinian evolution."
I'm no biologist, but when browsing through the first of these responses, a couple of rather glaring problems caught even my eye:
Under the promising heading 'Telling whether a speciation event has occurred', [Boxhorn] says that 'One advantage of the Biological Species Concept is that it provides a reasonably unambiguous test that can be applied to possible speciation events. Recall that under [this definition] species are defined as being reproductively isolated from other species. Demonstrating that a population is reproductively isolated (in a nontrvial way) from populations that it was formerly able to interbreed with shows that speciation has occurred.'
This only leaves one question: what exactly does Boxhorn mean by 'reproductively isolated'? A little later he tells us. 'Behavioral isolating mechanisms,' he says, 'rely on organisms making a choice of whether to mate and a choice of who to mate with.'
So there you have it. If two individuals choose not to mate then, according to Boxhorn's definition, they are 'reproductively isolated.' And if they are reproductively isolated then -- voila! They are now no longer the same species. A 'speciation event' has occurred.
This seems like a deliberate mischaracterization, if not a straw man. The determination of what is and what is not a species depends not upon individuals, but upon populations. Additionally, the example that he proceeds to give of size-discrepant dogs like Great Danes and Chihuahuas being "reproductively isolated" is actually untrue. If you ask your friendly local dog lover, they'll probably tell you many hilarious tales of smaller male dogs trying to mate with larger female dogs, or of tragic and messy results when the opposite is attempted. Comedy aside, such unions can and do happen - a dachschund/rottweiler cross, for instance, is hardly unheard-of.
Milton's conjecture about Boxhorn only using behavioural isolation as a delineating factor between species because he's writing a FAQ defending evolution is similarly bogus. Including behavioural isolation in the definition of species is quite common in biology, and characterizing it as some kind of dodge on Boxhorn's part seems ignorant at best and intellectually dishonest at worst. Of course, defining what exactly makes a species is a pretty controversial topic and probably will be for a long time to come, so for now we can accept Milton's rather conservative definition - a population can only be said to be a different species from its neighbours when a union between the two produces either no offspring or infertile offspring. While some would of course argue that two populations that are behaviourally isolated - say, due to the fact that one mates in winter and the other in summer - should not be considered different species on this basis alone, I doubt anyone would argue that two populations that cannot produce fertile offspring through interbreeding are the same species. Amazingly, Milton manages to find a well-supported example that fits this rather strong defintion of speciation, though he doesn't recognize it. Here, he quotes a citation from the FAQ:
5.3.1 Drosophila paulistorum
Dobzhansky and Pavlovsky (1971) reported a speciation event that occurred in a laboratory culture of Drosophila paulistorum sometime between 1958 and 1963. The culture was descended from a single inseminated female that was captured in the Llanos of Colombia. In 1958 this strain produced fertile hybrids when crossed with conspecifics of different strains from Orinocan. From 1963 onward crosses with Orinocan strains produced only sterile males. Initially no assortative mating or behavioral isolation was seen between the Llanos strain and the Orinocan strains. Later on Dobzhansky produced assortative mating (Dobzhansky 1972).
I had to read this twice to assure myself that it wasn't a practical joke. Boxhorn is saying that two fruit flies which he asserts are different species, successfully mate and produce offspring (thereby proving conclusively that they are not different species but the same species.) He calls the offspring 'hybrids' in an attempt to smuggle their 'different' species status in by the back door. Later some of the offspring exhibit 'behavioural isolation' (like Chihuahuas and Great Danes) but this is irrelevant as a sign of species status. So where, in all this, is there an instance of speciation -- or one species turning into another?
Milton's response here seems to be a complete misunderstanding of the FAQ's citation. While the Colombian strain was initially able to produce fertile hybrid offspring when mated with the Orinocan strain, the same was not true five years later. Attempted crossbreeding of the same Colombian strain with conspecific Orinocan strains produced only infertile male offspring, indicating that speciation had occurred. Behavioural isolation appeared only later on in the study (assortative mating, in this case, is a form of whole or partial behavioural isolation).
Either Milton has misread the article or he has failed to understand his own carefully chosen definition of what constitutes speciation. By any defintion, even the behaviour-independent one used by Milton, while two species may produce offspring through interbreeding, they cannot be considered the same species unless the result of such a union is fertile. By citing this study, Milton has completely shot himself in the foot - a population of Drosophila, once able to produce fertile offspring when crossed with conspecific populations, became unable to do so with the same populations after five years of reproductive isolation. This is speciation, and unless I've missed something major in my reading of Milton's article and the quoted FAQ it seems ridiculous to characterize it otherwise.
There are a few more errors and fallacies in Milton's articles, and I might go into them sometime later. Incidentally, the guy who linked me to this article is a veritable fountain of crazy on his own - he think evolution is bunk, not because he's a creationist, but because he believes Falun Gong tells him otherwise. Homosexuality is unnatural and immoral, lasers are actually death rays from Atlantis, Shangri-La was razed to the ground by the Chinese Communist Party to prevent a spiritual awakening by the Chinese people, and Edgar Cayce was the greatest prophet the world has ever known. He also believes himself to be a reincarnation of the Egyptian god Thoth. I could probably get a whole series of articles out of him, but I suspect there's more on the way, so I'll hold off for now. In the meantime, expect more entries on Milton in the future!
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