Thursday, October 18, 2007

'Race' and Evolution

James Watson, co-discoverer of the DNA double-helix, said in a recent interview that, effectively, blacks are, on average, less intelligent than other races. Here's the quote (via the ABC News link above) from an article quoting Dr. Watson:

"He says that he is 'inherently gloomy about the prospect of Africa' because 'all our social policies are based on the fact that their intelligence is the same as ours-–whereas all the testing says not really,' and I know that this 'hot potato' is going to be difficult to address. His hope is that everyone is equal, but he counters that 'people who have to deal with black employees find this not true.' He says that you should not discriminate on the basis of colour, because 'there are many people of colour who are very talented, but don't promote them when they haven't succeeded at the lower level.' He writes that 'there is no firm reason to anticipate that the intellectual capacities of peoples geographically separated in their evolution should prove to have evolved identically. Our wanting to reserve equal powers of reason as some universal heritage of humanity will not be enough to make it so.' "

As many know, Dr. Watson doesn't exactly have a great reputation: after all, his and Francis Crick's discovery was based on data stolen from Rosalind Franklin, and there have been stories about his male chauvinist views. Thus, many will be quick to write this statement off as a personal racist streak. And perhaps he does harbor some racist views--one particular sentence is telling: "His hope is that everyone is equal, but he counters that 'people who have to deal with black employees find this not true." Here, he is erroneously attributing a group average to individuals, encouraging the extrapolation of a generalization to particular individuals, and vice versa, the stock in trade for prejudice and stereotyping.

But what about the rest of his statements? Let's consider what he is saying, starting with his last statement.

"There is no firm reason to anticipate that the intellectual capacities of peoples geographically separated in their evolution should prove to have evolved identically. Our wanting to reserve equal powers of reason as some universal heritage of humanity will not be enough to make it so."
Despite the many problems with defining and testing something like "intellectual capacity", we should be able to agree that there is something called "intellectual capacity" that we all have. It should also be clear that, unfortunately, not everyone has an equal intellectual capacity: simply look at true geniuses and the severely mentally handicapped in any population. Now we've established that a wide variation of intellectual capacity exists; some is certainly due to environmental factors, but some portion has to be due to our genes, our DNA. After all, we aren't smarter than fruit flies because of our upbringing and diet.

Now let's talk a bit about human evolution. The current generally accepted theory is that modern humans evolved in Africa and that a couple groups left Africa, maybe in several waves, to colonize other areas. Those groups located nearby geographically will tend to intermix their genes readily, while those geographically far apart (by distance alone or by barriers such as oceans or mountain ranges) will exchange genes rarely, if at all. If any population is split into two isolated or nearly-isolated groups, the groups will change (read: evolve) differently from each other. These differences are very apparent in facial structure, skin tone, and other obvious physical characteristics.

It is important to note that this distinction only works when looking at widely disparate parts of the globe. If you were to move systematically from one place to another across the land, (say from Eastern Africa to China) you would see a gradual shift from one set of characteristics to another. This is an important observation, and I hope the consequences of it are not lost on you; I will touch on it again later.

Returning to the general differences observed in disparate human populations, if we can see fairly big differences in visible surface features, why could there not be differences in other characteristics? And why couldn't one of these be intellectual capacity? It seems like a fair inference to make, given that we've established that genes can impact intellectual capacity, whatever that really is. Thus, it is possible that disparate groups of people can differ in intellectual capacity.

Now we can start to evaluate the portion of Dr. Watson's statement mentioned above. We have established that "the intellectual capacities of peoples geographically separated in their evolution" can conceivably differ. Do we have, as he claims, "no firm reason to anticipate" that intellectual capacity would evolve identically in all human populations? Well, it seems unlikely that much 'downward' divergence would occur from a base level. However, it is entirely possible that all groups did tend to increase in intellectual capacity, but at differing rates. Thus, it does appear that this claim is also true. Given this, it should of course be apparent that "wanting to reserve equal powers of reason as some universal heritage of humanity will not be enough to make it so" -- if indeed groups of humans vary in the "powers of reason," no amount of wishing will change that fact.

"He says that you should not discriminate on the basis of colour, because 'there are many people of colour who are very talented, but don't promote them when they haven't succeeded at the lower level.'"
Now we've established that it is entirely possible for different groups of humans to differ in intellectual capacity. Before I discuss this portion of the statement in full, I must touch on the concept of 'race' in biological terms. Contrary to what you might believe, species are not discrete units that have specific, defined boundaries. 'Species' are neat designations imposed on a messy world, to allow us to have some hope of grappling with it. Biologists understand that the borders of what is a species is often very fuzzy: there are examples of groups of animals where two fairly similar groups can interbreed with an intermediate group, but the two extreme groups cannot interbreed with each other (See Wikipedia: Ring species). Species distinction can only be seen between two geographically separate groups of animals, while there may be a constant variation seen when moving from the region of the first group to the region of the second group.

Sound familiar? The same thing is seen in a biological treatment of race: distinctions can be apparent in the extremes, while the races may appear to blend together in-between. Race-designation, like species-designation, is an artificial categorization imposed on a messy world. However, the artificial nature does not mean the designation is useless. It should also be emphasized that race here does not necessarily relate to skin color. It relates to ancestry from a historically isolated population relative to other populations. (As an aside, race distinctions will diminish as increased genetic mixing between disparate populations occurs.) These populations will have unique distributions of genes, potentially resulting in different phenotypic (displayed) outcomes.

Now let's return to this part of the statement. Let's assume, for the moment, that we have a good definition of intellectual capacity (which we don't), and that we have a good way to measure it (which we don't, and quite possibly can't), and for the sake of argument let's assume he is correct that people of African descent have, on average, less of an intellectual capacity. What does this mean? Well, it means that if you were to apply the ideal test to people of African descent, and obtained a mean, that number would be lower than that obtained for people of other descent. The mean is a value that indicates that (assuming an even, or 'normal', distribution) 50% of individuals are above that value, and 50% of individuals are below that value.

However, this doesn't tell us anything about how two populations relate to each other. In fact, it is highly likely that, even if the average does really differ, variation of the two populations would overlap so much that it would be incorrect to take the (potentially true) sentence "blacks, on average have less intellectual capacity than whites, on average" to mean the (patently false) sentence "all blacks have less intellectual capacity than all whites." You similarly cannot use the first statement to imply that any particular individual has a greater or lesser intellectual capacity than any other. This problem is further compounded by the inherent fuzziness around the borders of what we consider to be races. This is why discrimination based on race, even with evidence such as we have been discussing, makes no sense; this is exactly what Dr. Watson said. The second part of the above statement just makes sense: sure, promote those who do well regardless of race, but don't promote those who aren't quite there simply to meet some ideal of diversity.

Of course, even if all of this might be true, some would say that we should forbid any inquiry into such matters as sex differences or racial differences because it encourages the generation and maintenance of prejudices. I reject this type of claim on its face. Forbidding intellectual inquiry simply because it could generate 'harmful knowledge' has never made sense. Certainly a racist (or sexist, etc.) could seize on such knowledge as proof of their beliefs; however, their inability to grasp the difference between group averages and individuals ironically places them in the lower reaches of the intellectual capacity scale, and they would be unlikely to change their minds even if evidence showed the opposite was true.

Even if Dr. Watson has some racist tendencies, his overall statement and conclusions are not illogical in and of themselves; however, we would need a much more robust, culturally- and educationally-neutral way to determine intellectual capacity before we could make such a firm conclusion in any direction.

So what about his claim regarding Africa? It could, conceivably, be a factor, but the more important contributors to difficulties in aiding Africa are likely environmental and cultural. It's better for all involved to assume the latter.

Update: Dr. Watson has disclaimed his entire comments (CNN), though more likely to calm down the resulting firestorm than because he really didn't mean them, though his premise that there are good data supporting his claim is specious at best. As you can see, the reasoning behind the issue is complex, and may be difficult for some people to grasp, if they are paying attention through the whole explanation. It was probably easier for him to apologize than to try to explain.


  1. Nick:

    This was very well-written and even though we clearly don’t see the same way on the existence of human races, I think you managed to present a good argument against Watson.

    I am not fully aware of how intellectual capacity is measured. Can it be understood using IQ tests, or is it inferred from general economic success (which seems to be Watson’s gauge)? My argument against the validity of the former would be that IQ tests are culturally tainted in that they draw on certain assumptions of general understandings of the world that are Western. My argument against the validity of the latter gauge can be summarized as follows: “The world in which you were born is just one model of reality—other cultures are not failed attempts at being you.” (Quote taken from a poster in the Anthro wing).

    The main reason why Africa is poorer than almost all of the rest of the world is the fact that the continent was hit extremely hard by colonialism. Slavery exported the continent’s most able human capital; colonial economies did nothing to promote economic growth in Africa as the continent’s resources were shipped to Europe; and in the postcolonial context, African states (whose borders were arbitrarily defined by their colonial rulers without consideration for historical and cultural associations) still struggle with civil unrest that can be traced back to colonialism. In the United States, it is no secret that African Americans’ opportunities have been limited by racist social structures from slavery and Jim Crowe to white flight and unnecessary degree requirements for jobs that hit African Americans harder than other groups in the U.S. I am not saying that you are wrong (nor that you are right) stating that intellectual characteristics might differ between populations just as other (more visible) characteristics can, however, I strongly oppose to involving popular notions of race into that reasoning. In general, I am offended by the idea that Western scholars have the right to define what mental power is and how it can be attained. I think there are many aspects of life in less complex hunting and gathering societies that point to outstanding mental power and ingenuity foreign to urbanized Westerners. I mean, how many liberal arts college students would be able to lead productive lives—let alone survive—in some of the harshest environments on earth where some civilizations have thrived for millennia?

    In other words, a fair gauge of intellectualism must take into consideration such a vast and intricate set of skills and abilities that any universal measure would be obsolete. Seeing as we know that the skills required to get by in different societies differ greatly from place to place, why even try to measure brain power (a more direct and less eloquent definition of intellectual abilities) across localities, especially since doing so would inevitably involve a fair amount of ethnocentric methods?

    Ending this lengthy response, I am curious to learn the scientific take on gauging intellectual capacity… if there is one that is.


  2. You make some very excellent points, Kris, and I think they complement my discussion very well. I really wanted to address the underlying biological sense to his claim, rather than the veracity of the premises themselves.

    I understand the aversion to invoking the concept of race, though I'm hard-pressed to come up with an alternative that would not simply be related straight back to the term 'race'. Terms used in similar situations in animals by biologists could lead to even greater offense.

    To address your concern about defining intellectual capacity, I agree that there is no good one. I don't believe that there is a good scientific notion of intellectual capacity, at least any that can be tested. As you pointed out, most tests of intelligence are extremely culturally-biased. That's why I resorted to a hypothetical definition and test in my explanation.

    We can certainly imagine that there is something we can consider to be "intellectual capacity", but it would be nearly impossible to isolate it from environmental impacts and in a way that doesn't depend on the culture. So there really isn't a good 'scientific' way to measure this, at least not yet.

    And regarding another point you mention, about Western people being able to survive the harsh conditions some other cultures have to go through... The argument I made is certainly not a one-way street, and it's just as likely that one group would lose something compared to another group as to gain something else. I would actually be surprised if this wasn't true.

  3. I ran into your blog while trying to come up with a name for my blog. Impressive logic, focus, and ability at writing it down. Nice to see random people actually think a lot out there.