John Mackay displays his lack of knowledge with the strings of quotations he presents below from evolutionary biologists. This is a popular practice in the young-earth creationist literature: quote some evolutionary biologist out of context so they sound like they’re disagreeing with evolution when they aren’t.
In his debate summary, he quotes Gould: “…our ability to classify both living and fossil species distinctly and using the same criteria, ‘fit splendidly with creationist tenets,’” as though Gould is saying that the variety of living and fossil creatures supports creationism. That’s not what he’s saying, as Gould himself complained in no uncertain terms, many years ago here. (Do you not check your sources at all, Mr. Mackay? This quote-mine was exposed back in 1984!) The quotation comes from p. 205 of The Panda’s Thumb, where the complete quote is: “This notion of species as ‘natural kinds’ fit splendidly with creationist tenets of a pre-Darwinian age.” First, he makes no mention of fossils at all – that’s just added in! Second, he is talking about what people used to think pre-Darwin. Third, he goes on to explain how evolutionary theory gives a much better account of what we find: a mix of stability and change throughout the fossil record.
What we don’t see are unchanging natural kinds, as they used to think – for example, there are hundreds of identified dinosaur species that we obviously don’t see today, and that are found only within a restricted range of strata in the fossil record: wikipedia’s list. Instead we see birds today, whose dinosaur ancestry (or at least cousinhood) is indicated by many different facts, including: skeletal similarity (vertebra, feet), similar lungs,and a collagen structure that is closest to modern birds. (For a basic summary of some of this information and more, see here.)
The next case of quote mining: Mackay quotes evolutionary biologist Thomas Kemp on the “sudden” appearance of “new taxa” in the fossil record, and a biology textbook to the same effect. “Sudden”, here, means on the order of hundreds of thousands of years, which already contradicts Mackay’s view that the earth is merely 10,000 years old. Second, the “new taxa” are often very similar indeed to related taxa: e.g. barosaurus and diplodocus (or other diplodocoids). If these are new “kinds”, using the meaningless creationist term, then a chihuahua is definitely a different kind from a great dane, and it’s game over for Mackay. (He has to maintain that all dogs are the same “kind”, or else he would have to admit that new kinds can come from old ones.)
In the quotations, Kemp and the textbook are discussing an issue within evolutionary biology concerning how rapid evolutionary change can be: when environmental change is rapid, evolutionary change can be too; when the environment is stable, so (typically) are species. If evolutionary change is caused by environmental selection, this is exactly what we would expect. These folks, who are staunch advocates of evolution, would be shocked to learn Mackay is misusing them as fake support for young-earth creationism.
Next case: In his new post (“Family Trees”), Mackay quote-mines an article from New Scientist in 2009 discussing the transfer of genetic material by methods other than reproduction. For instance, it has long been known that one bacterium can transfer short segments of DNA to another bacterium by connecting through a tube – a process known as “conjugation.” This is like the process whereby a language can borrow a term from another, rather than from its parent language(s): for example, we got “pajama” from Hindi-Urdu, not from the parent languages of Anglo-Saxon or medieval French. What this means is that, in bacteria and other single-celled creatures, common descent has a network or web shape rather than a tree shape. (This is also true, though to a much lesser extent, for multicellular creatures like us.)
When Mackay quotes these scientists as questioning the “tree of life”, they are merely suggesting that common descent takes the form of a web rather than a tree. They are not questioning common descent; rather they are displaying the incredible knowledge that we are acquiring about the details of common descent (just as we are about the common descent of languages using exactly the same methods). For example, Mackay quotes Eric Bapteste saying “We have no evidence at all that the tree of life is a reality” [rather than a web, I might add!], but conveniently leaves out Bapteste’s later comment: “The tree of life was useful. It helped us to understand that evolution was real.”
I’ll have more to say about the language analogy in the post after my next one.