Thomistic, the author at RCB, rightly notes that there is certainly no inherent conflict between Catholic doctrine and either an old Earth or the gradual development of species. However, he does seems concerned by some of the points that Coulter brings up, as do some of his commenters.
The anti-evolution arguments that I'd like to cover based on the post are:
1) Evolution is the intellectual justification for genocide and totalitarianism by 20th century figures such at Hitler and Stalin.
2) Evolution is problematic for Catholic doctrine because the doctrine of Original Sin requires that there be a single historical Adam and Eve, and evolution makes this problematic.
3) The evidence doesn't even support evolution, since no one has ever found a fossil of an animal halfway in between species.
-- 1. Evolution as Justification for Evil --
Thomistic quotes an article about Coulter's book which summarizes this line of argument as follows:
As Coulter puts it, "From Marx to Hitler, the men responsible for the greatest mass murders of the twentieth century were avid Darwinists." As evidence of this, one can cite Richard Weikart's book From Darwin to Hitler, wherein the author traces the evidence that eugenics organizations in Germany at the dawn of the 20th Century touted "scientific" theories of the laws of evolution.To start with, Coulter is indulging in some sadly characteristic sloppiness when she labels Marx as an avid Darwinist. Marx and Engels published the Communist Manifesto in 1848, eleven years before Darwin published the Origin of Species in 1859. What Ms. Coulter (and perhaps Mr. Weikart, if his guilt may be determined by association) seems to have missed in her cultural analysis is Marx and Darwin were drinking from the same pool of cultural fascinations rather more than directly influencing one another. The mid to late nineteenth century was teaming with notions of golden ages, progress, regress and rebirth. In many ways, the notion of progress of some grand, world-transforming sort was taking the place which salvation had once filled, for what was already a secularizing Europe. Indeed, one of the ideas that it took nearly a hundred years to purge out of evolutionary thought was the idea that evolutionary change was necessarily directional: "upward" from simpler, baser creatures to more complex, "better" ones.
As science replaced religion as the key to deep knowledge (there is, I think, a certain gnosticism about the popular attitude towards science from the mid nineteenth century through the Great War), scientifically framed ideas of progress came into vogue. And from them (with a generous splash of poorly absorbed evolutionary theory) came the fantasies of eugenics or breeding a "super race" which fascinated the likes of Hitler (and Margaret Sanger and Oliver Wendel Holmes and many others).
The theory of evolution provided a certain fodder to the evils of the 20th century, but I don't think one is any more reasonable to dismiss the theory qua theory because of it than one would be to reject Newton's physics because they helped create the cultural climate of the Enlightenment, and thus fed the blood-fest of the French Revolution.
-- 2. Adam, Eve, Evolution and Original Sin --
From a doctrinal point of view, the most commonly cited objection to evolution based on Catholic doctrine is the question of original sin and whether all of humanity is indeed descended from a single set of parents who fell from grace and caused the original rupture in the relationship between God and humanity.
In the encyclical Humani Generis, Pope Pius XII wrote: "[T]he faithful cannot embrace that opinion which maintains either that after Adam there existed on this earth true men who did not take their origin through natural generation from him as from the first parents of all, or that Adam represents a certain number of first parents. ... [I]t is in no way apparent how such an opinion can be reconciled... with regard to original sin which proceeds from a sin actually committed by an individual Adam in which through generation is passed onto all and is in everyone as his own."
I think in regards to this kind of thing it's important to keep clear in one's mind what elements of the Adam and Eve story are essential de fide and which are not. I think that the essential elements are clearly that:
- God created two first humans, who are the parents of the whole current human race.
- These first parents sinned directly against God, despite their originally having a more direct relationship with him than we do.
- We all bear the mark of original sin: both a tendency to do wrong and a gulf that separates us (as a tribe) from God.
The idea of there being other human-ish creatures wandering the Earth at the same time as Adam and Eve doesn't fit well with the standard Sunday school version of the story, but the Bible itself is slightly odder than the children's version. Recall that at several point in the early chapters of Genesis people are mentioned as going off and interbreeding with other creatures (giants, 'the sons of heaven', etc.) Indeed, after the initial description of the time in the garden itself, one doesn't necessarily get the impression that Adam and Eve are alone in the world. (Why, for instance, does Cain fear that when he is banished people will kill him? He's just killed one of the four named people in the world up to that point, and the other two are his parents.) Rather, Adam and Eve seem to be described tribally: as the tribe of true humans, but not necessarily the only creatures on Earth. Now, the idea of early (ensouled) humans interbreeding with (soul-less) human-ish creatures is unappealing. But then, the idea of Adam and Eve's children having no options other than incest isn't exactly appealing either.
I think it's important to remember that (without denying the truth of the stories of the creation and fall) the early parts of Genesis were never meant to be anything like a historical or scientific test. The stories about Adam and Eve and their children convey a number of important truths, but in other senses the narrative is sketchy and disjointed. I don't think it's meant to answer questions like: Who did Adam and Eve's children marry?
From a Catholic point of view, we have the doctrine of Original Sin, and that that sin is the result of a transgression committed by our first parents. Beyond that, I don't think that part of the Bible is meant to satisfy the historical and scientific areas of our curiosity.
-- 3. There are no fossils of transitional forms --
This isn't really a question with any specifically Catholic relevance, but one of the commentors over on RCB brought it up, and it's a favorite of anti-evolution writing. Coulter, characteristically, deploys a particularly loud and uninformed example of this set of claims in Godless.
I won't spend a ton of time on this here, since the post is already so long, and I've already covered the issue of speciation a bit here. However, let me just take the time to point out that the most basic flaw in this line of reasoning is that it fails to take into account how paleontologists do their work. When a paleontologist finds fossils from a given individual, one of the things he seeks to do is classify it as belonging to a species. If it seems very late or very early (in relation to the time period during which the species is generally found) or if its characteristics seem on the edge of what would be considered normal for that species, he may consider classifying it as belonging to a different but similar species. Or he may classify it as belonging to a known species, but as an outlier within the set of characteristics generally found in that species.
What he won't do is say: "Well gosh. This critter doesn't seem to be in a species. What we have here is a transitional form. I better not put this one in a species." Everything is assigned to a species, because it is by classifying it as belonging to a particular species that the paleontologist can convey how he believes that individual is related to other populations of creatures.
Thus, the argument that evolution is disproved because scientists have only found fossils of creatures that belong to species, not transitions creatures, isn't a "gotcha", it's display of basic ignorance.