The Tribulation Force (Warning: the site has music), named after an organization from Tim LaHaye’s Left Behind novels, has a file listing a bunch of common out-of-context quotations taken from the writings of various scientists to give the false impression that the fossil record does not support evolution.
Here is one of them, which I will reproduce in full:
TEXTBOOK DECEIT, GEORGE G. SIMPSON, “The uniform, continuous transformation of Hyracotherium into Equus, so dear to the hearts of generations of textbook writers never happened in nature.” LIFE OF THE PAST, p.119
Of course the impression that they are trying to give is that George Gaylord Simpson, a great paleontologist, has rejected the fossil series showing the evolution of the horse. He did no such thing. He was not trying to debunk that the fossil record supports evolution, nor was he trying to debunk notions of horse evolution shown in the fossil record. This quote, from a 1953 book, is flagrantly out-of-context.
When one bothers to check what Simpson actually wrote, one finds that Simpson was talking about in the quote the creationists quoted to an old discredited notion called orthogenesis. Orthogenesis was an idea that was popular in the late nineteenth and very early twentieth century but has been rejected by scientists since no one could provide a viable mechanism for it and more importantly the evidence showed it to be wrong. Orthogenesis is the notion that evolution proceeds in straight lines. This can refer to the idea that evolution proceeds straight from species A to species B without any side branches. More importantly, it refers to the idea that an evolutionary lineage changes steady, uniform way with no reversals. Sometimes, but not always, it was imagined that species were evolving steadily towards a goal. Usually this trend was supposed to be caused by some “mysterious inner force” (to use Simpson’s words) of the species that compelled it to evolve. Some supporters of orthogenesis would say that once a trend got started in a lineage that it would unchangingly continue until extinction occurred.
Lets use some concrete examples to illustrate what this meant. Supporters of orthogenesis had pointed to the sabertooths. They claimed that the sword-like canine teeth of these cats over evolutionary time continuously got bigger until they were overgrown to the degree which they caused the animals extinction. Simpson pointed out that at least forty years (now ninety years) that those who studied sabertooth fossils stated that it was not so:
The earliest sabertooths had cannes relatively about as large as those of the last survivors of the group. For some forty million years of great success the canines simply varied in size, partly at random and partly in accordance with individual advantage to species of various sizes and detailed habits. The famous trend for the sabers to become larger did not really occur at all.
Another example, which Simpson did not use, was that of the “Irish Elk” and its huge antlers. You can read about it here or in essay 9 of Stephen Jay Gould’s book Ever Since Darwin: Reflections in Natural History.
The context of the of the creationists quoted was simply that orthogenesis was wrong:
The word “orthogenesis” has been used in so many different ways that it really has no exact meaning any more and is being dropped from the vocabularies of careful paleontologists. In the meaning given it in the last paragraph, which is as common usage as any, it is now conclusively known that there is no such thing as orthogenesis….
We now have the background required to look at what Simpson was referring in that sentence which the creationists quoted. He was showing that the horse is not an example of orthogenesis:
The evolution of the horse family included, indeed, certain trends, but none of these was undeviating or orthogenetic. The uniform, continuous transformation of Hyracotherium into Equus, so dear to the hearts of generations of textbook writers, never happened in nature. Increases in size, for instance, did not occur at all during the first third of the whole history of the family. Then it occurred quite irregularly, at different rates and to different degrees in a number of different lines of descent. Even after a trend toward larger size had started it was reversed in several groups of horses which became smaller instead of larger. As already briefly noted, the famous “gradual reduction of the side toes” also is something that never happened. There was no reduction for the 15 or 20 million years of the history. There was relatively rapid reduction from four front toes to three (the hind foot already had only three toes). Many horses simply retained the new sort of foot without further change. In one group there was later another relatively rapid change of foot mechanism involving some reduction in size of the side toes, which, however, remained functional. Thereafter most horses retained this type of foot without essential change. In just one group, again, another relatively rapid change eliminated functional side toes, after which their descendants simply retained the new sort of foot. (Fig. 39)
In the history of the horse family there is no known trend that affected the whole family. Moreover, in any one of the numerous different lines of descent there is no known trend that continued uniformly in the same direction and at the same rate throughout. Trends do not really have to act that way: there are not really orthogenetic.
(The evolution of the horse family, Equidae, is now no better known than that of numerous other groups of organisms, but it is still a classic example of evolution in action, and a very instructive example when correctly presented…) [My emphasis.]
Thus it absolutely clear that Simpson did not in any way reject horse evolution or mainstream science’s account of it. He was showing that an idea that was long discredited in science, but unfortunately common in textbooks and popular presentations of evolution, was wrong. Indeed scientists, of virtually every field, rant on the presentations given in textbooks and by popular media presentations.
Also see: Horse Evolution