Evolution 101

Sunday, August 27, 2006

Is Evolution Racist?

Let's start with some listener email...

Christopher asked if the imperfection of the fossil record is a serious problem for evolutionary theory. In other words, since these evidences are not capable of reproduction in a laboratory setting, don’t they fall outside the aegis of actual science? Not really. You see, the scientific process is one in which observations of the natural world are necessary for the investigatory process. Experiments, especially those conducted in a laboratory setting, are used to remove as many variables as possible. But this does not mean that observations made outside the laboratory are worthless. Paleontology, which is the branch of scientific inquiry that studies prehistoric animals by examining their fossil evidence, is unable to perform variable-controlled experiments in the classical sense, but that doesn’t matter. The scientific method isn’t just observation-hypothesis-experiment-conclusion, like you probably learned in school. The purpose of the experimental component is to generate data. If your observations are about living animals, such as mice, well, then you probably can set up an experiment in the laboratory that will provide you data about that animal. But if your observations are about long-extinct animals, then the only source of data lies in the fossils that you can discover. This is why paleontologists spend so much time out in the field, whereas molecular biologists spend so much time on the laboratory bench. We’re both in search of data, but because of the differences in our focus of study, we have to find that data in different ways.

Daniel asked if much of the information about Darwin that appears in science textbooks and popular literature, such as his being hired as the naturalist on the Beagle, and his observing the finches on the Galapagos are actually apocryphal. Well, technically, Darwin was not hired as the naturalist on the Beagle. After graduation from seminary, Darwin had intended to visit the tropics with a friend in order to indulge his interest as a naturalist, but these plans fell through when his friend died. He found a berth on the Beagle because of the recommendation of his mentor, the Reverend John Henslow, but his position was not paid and it was not as a naturalist. He was the gentleman’s companion of the captain of the Beagle, and just indulged his interest in naturalism in a purely amateur capacity. This was not a typical arrangement, however, the previous captain of the Beagle had committed suicide on its preceding voyage. The new captain, FitzRoy, was worried about the loneliness of life as a captain, and requested that a companion be found for him. He had suggested finding a naturalist, since they frequently were members of voyages as passengers, in the interest of furthering their discoveries. Darwin happened to be one of the ones suggested, and the only one who agreed to them arrangement. The captain had someone interesting to talk to during dinner, and Darwin got to explore South America, the Galapogos, and Australia. Win-freaking-win. While visiting the Galapogos, it is true that Darwin didn’t really pay much attention to the finches there- he was more interested in the different species of mockingbirds on the island. However, once he had returned to England and began to formulate his theory, he realized that the finches there were an important piece of evidence, and got more information on them including better-labeled specimens from others who were on the Beagle. But the finches themselves exist, and have been studied in depth since Darwin, confirming his theory.

Gary asked about chromosomes- what makes a chromosome, how can species with different chromosome numbers interbreed? Well, if you can envision your genome, that is- the entire collection of genetic information in each cell of your body- as a library, then a chromosome would be one book in that library. We number them by size- the largest chromosome is number 1, the second-largest is number 2, and so on. Humans have 22 regular chromosomes, or autosomes, and two sex chromosomes, X and Y. In order for sexual reproduction, we carry two copies of each chromosome, with a total number of 46, except for those cells that are used in reproduction, spermatocytes or oocytes, which only have 23. Hybridization between species with different chromosome numbers is only possible for species which are closely related enough to have very similar chromosome numbers. For example, horses have 64 chromosomes, and donkeys have 62. The hybrid of the two species, the mule, has as a result 63. The reason for this, if you recall what I said about the sex cells, is that the horse contributes 32 chromosomes, and the donkey only contributes 31. 32 and 31 is 63. Since this is an odd number of chromosomes, any attempt to form sex cells in a mule will fail, because there has to be an even pairing of chromosomes for successful meiosis, and the mule will always have one extra. Other hybrids with an even number of chromosomes may be fertile, but it’s usually the female that is, according to Haldane’s Rule. This rule comes from the evolutionary biologist J.B.S. Haldane, who observed that the heterogametic sex (usually the male) is likely to be sterile or rare in a hybrid cross. The reason for this is that, certain genes which are necessary for fertility or viability will be found on the sex chromosome of one species but not another, and so when the two are mixed, the correct configurations of genes are not present. This is less of a problem for females, since they carry two copies of their sex chromosome, and thus have a built-in backup.

Jay asked about the scientific refutation of creationism. He noted that in the final installment of my series on the molecular evidence for evolution, I pointed out that the creationist response amounts to an argument from ignorance, or a “God of the Gaps” approach. However, since the creationist position itself is not a scientific claim, he wondered how I as a scientist could refute it. Well, Jay, that’s an accurate observation, and I’m in total agreement with you. Creationism is a theological position, not a scientific position, and the only basis which I use to interact with it is on those grounds. The only thing I’m interested in doing is refuting those creationists that claim either that creationism is science, or that evolutionary theory is not science. In regards to the molecular evidence, I want to make it very clear that the creationist response does not have scientific merit, and that’s it.

Steven asked about a connection between evolutionary theory and racism. This is an important question, and I want to spend the rest of the time for this podcast on the subject, particularly because a new program has been produced by Coral Ridge Ministries, called “Darwin’s Deadly Legacy.” This program is hosted by Dr. James Kennedy (a theologian, not a scientist) and features Michael Behe as the only scientist, specifically for his views on irreducible complexity, which I’ve gone over in this podcast already. The rest of the experts interviewed are those who are already famous for their rejection of evolution, such as Ann Coulter, Ken Ham, Jonathan Wells, and others.

I want to avoid any theological criticism of this program, but I’ll just point out that it seems to me that this kind of attack on evolution only seems to come from those with a theological bent against it, which I’ve mentioned before.

But what about the question at hand? Is evolution racist? Well, quite frankly, no. Racism is the position that certain races are “better” than others. This is a moral and proscriptive position, whereas evolution is a scientific and descriptive position. Evolutionary theory doesn’t make any kind of claim concerning which species are “good” or “bad.” It simply predicts that, as I’ve said many times, gene frequencies will change within a population over time. Science is a wonderful tool for explaining reality, and it can be used to inform our moral values, but it cannot generate them for us. To claim that one can do so is to invoke the naturalistic fallacy- that is, to claim that because something is natural, it is right to do. Or in other words, to transition from an “is” to an “ought.” Any person who uses scientific facts to derive their moral position in this way is thus violating logic.

That being said, there have been many instances throughout history of people committing this fallacy in regards to evolution. Firstly, it’s important to bring up the point that racism existed long before Darwin was even born. It may seem somewhat strange to realize, but racism was really more like the default position for everyone throughout the world. It just so happens, due to the circumstances of history, that Europeans have, at least in the past several hundred years, been in a unique position of power to institute their racism to a scale which was previously not possible. The rise of colonialism meant that European power extended all over the globe, whereas before each group of people were confined, more or less, to their own small geographical patch of earth.

Darwin himself would be considered racist by today’s standards, but then again, so would pretty much everyone in his society. In fact, by his own society’s standards, Darwin was less racist than most, because he believed that all humans were members of the same species, whereas many others believed that the different races were actually different species. Of course, science now demonstrates clearly that racial differences are very minor in terms of overall genetics- there is more total genetic variability among members of a particular “race” than there are between two average members of different races. The examination of gene flow among the races by comparing genetic sequences shows that there has been an incredible amount of mixing all throughout history- the pattern of descent looks less like a simple tree-branching pattern, and more like a back-and-forth ivy vine.

A pretty good analogy for the concept of race can be seen in the different breeds of domesticated animals. Humans have amplified certain traits through artificial selection to generate different breeds of dogs, for example. But is a rottweilier a “better” dog than a cocker spaniel? Is a Siamese cat “better” than a Manx? Is an Arabian horse “better” than a Thoroughbred? It makes no sense to talk this way, just as it makes no sense to talk about “races” of humans as “better” than others, especially scientifically.

But there have been people in history who have made such claims, despite the lack of scientific justification. Interestingly, the beginning of this in modern history begins not with Darwin, but precedes him in an essay written by Joseph de Gobineau titled, “On the Inequality of the Human Races.” In this essay, he divided humanity into three main races, claiming the “Aryan” race as the most powerful. This idea influenced later racist theories. Later, when evolution was gaining acceptance, it was incorporated into these racist theories to posit that some races were “more evolved” than others. This idea is obviously incorrect, and I’ve talked before on this podcast about why the idea of certain species being “more evolved” is not supported by evolutionary theory at all.

This combination of evolution with pre-existing racist social theories came to be known as “social Darwinism,” although it’s not something that was advocated for by Darwin himself, or supported by his scientific theory. As applied, social Darwinism gave rise to the practice of “eugenics,” which is a directed and artificial selective process analogous to selective breeding in animals. Not surprisingly, those in power decreed that those groups which were not in political favor were “unsuitable” genetically, and had to be removed from the breeding population. Forced sterilizations were common all over the world, actually, during this time, including here in America. It was only after the practices of eugenics by the Nazis were publicized that public support for it dried up.

Eugenics actually runs counter to evolution, as you should be able to realize by now. Evolutionary theory shows that the genetic makeup of any given population is based on the selective pressures of its environment. This is a process that is in constant flux, but one thing is certain- every organism alive today is the ultimate descendent of a very long line of winners. You, and I, and everyone listening to this podcast are the product of an ancestry of only those people who were able to successfully survive and procreate. The results of evolution then speak for themselves. As long as you survive long enough to reproduce, evolution considers you a success, no matter what color your skin may be.

But what if evolution really was racist? What if Darwin was a racist? What if Hitler really did believe he was acting in accord with evolution? This has no bearing on the truth of evolutionary theory. Those people like Dr. Kennedy who attack evolution as racist are committing a different logical fallacy- the genetic fallacy. People who commit this fallacy make the argument that the truth of an idea is based on the source of that idea. This is a well-known logical fallacy, and is usually pretty obvious because Hitler is commonly used to condemn many other things beside evolution. However, if everything Hitler advocated was a bad thing, we have to take everything else he believed in as wrong. For example, in addition to being in favor of eugenics, he supported capital punishment, gun control, and vegetarianism. Among the things he opposed were atheism, capitalism, homosexuality, and pornography. Quite a grab-bag.

All right, so let’s review. Evolution is claimed, primarily by its creationist detractors, to be racist. However, as a scientific theory, evolution makes no proscriptive moral statement. In addition, the historical promotion of racism predates evolution, and those individuals who tried to combine racism with science were doing so in defiance of what science teaches. And finally, those who attempt to condemn evolution for the evils committed by individuals throughout history are committing the genetic fallacy. So no, evolution is not racist- but I have to wonder at those people who seek to characterize it as such- isn’t there any good scientific criticism they can use? I guess not.

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