Monkeys and Human Prejudice

Human See Human Do
Thomas Riggins

Where does human prejudice come from? What causes one group of humans to dislike and look down on another? Is this phenomenon inherent in the human species, or is it the result of cultural conditioning? What do scientists (or maybe "scientists") have to say about this?

Well, some scientists think they have the answer, as reported in ScienceDaily online on March 18, 2011 in an article entitled "Human Prejudice Has Ancient Evolutionary Roots."

As an introduction SD tells us that monkeys show prejudice "like humans" and that they are also "flexible" when letting others join their group. Now that monkeys can be territorial and hostile to outsiders is not disputable but that this is "like humans" is disputable. Now if the expression means outwardly and superficially similar-- as in "humans make love just like monkeys" that is one thing, but without knowing the inner cognitive state of monkey lovers it seems negatively anthropomorphic to say their love making is the "same" as humans. In the same way it is probably not correct to draw equivalencies between monkey and human "prejudice."

OK, what do the scientists actually have to say about this? SD reports that researches at Yale, headed by Laurie Santos, a psychologist, by conducting "ingenious experiments" have shown that monkeys treat outsiders "with the same suspicion and dislike" as humans do. This leads to the suggestion the "roots" of human prejudice and inter group conflict go deep into our evolutionary past.

"Pretty much every conflict in human history," Dr Santos said, "has involved people making distinctions on the basis of who is a member of their own race, religion, social class, and so on. The question we are interested in is: Where do these types of group distinctions come from?" Well, one answer may be that they come from the fact that there are really different religions and social classes. We should also note that some of the greatest conflicts in history were between members of the same "race" (a really outmoded term for a scientist to be using) conflicts between various European nations for example; the same religion (conflicts between various Christian nations, also within Islam) and the same social class as in the feudal conflicts between various kings and nobilities with each other. There are even many examples of people with the same "race", religion and social class fighting with each other. So insiders are just as likely to suffer "prejudice" as outsiders as far as humans are concerned.

Dr. Santos agrees that human culture is a factor, but she also thinks 25 million years of evolutionary development is also a factor. She came to this conclusions by studying the rhesus macaques [Macaca mulatta] living on Monkey Island (Cayo Santiago) off the coast of Puerto Rico. These are the descendents Old World monkeys who were transplanted to Monkey Island from India in 1938. They have the island to themselves and they serve as a research station for scientists. The website states, "Because of almost 70 years of research at this field site, subjects are well habituated to human experimenters." They also get free monkey chow provided by the scientists. Presumely the monkeys act the same way as their ancestors in the forests of India who were not habituated to humans and getting free monkey chow.

Santos' group gave various psychological tests to the monkeys and determined that, by looking at pictures of other monkeys, both in group and out group, monkeys looked longer at the pictures of out group monkeys and this suggested that they "spontaneously" detected strangers. This is because there is a "well known tendency" for animals to look longer at "novel or frightening things than at familiar or friendly things." Well, humans do that too I would think, so maybe the scientists are on firm ground in this respect.

Neha Mahajan, a team member, stated: "What made this result even more remarkable [why is a "well known tendency" remarkable?] is that monkeys in this population move around from group to group, so some of them who were 'outgroup' were previously 'in-group.' And yet, the result holds just as strongly for monkeys who have transferred groups only weeks earlier, suggesting that these monkeys are sensitive to who is currently to be thought of as an insider or an outsider. In other words, although monkeys divide the world into 'us' versus 'them,' they do so in a way that is flexible and is updated in real time." What is "flexible" about reacting just as strongly about former in, and now out, group monkeys as about monkeys that have always been out group. It seems to me this a "rigid" response: You are all the same, outies!

Using a test they devised based on the IAT (Implicit Association Test) which claims to test humans for "implicit biases" against others, the research group concluded, according to SD, that, "Like humans, monkeys tend to spontaneously view ingroup members positively and outgroup members negatively."

As a result of the Monkey Implicit Association Test they devised, the researchers think "the roots" of human prejudice may be 25 million years in the making since that is how long it has been since we shared a common ancestor with the rhesus monkeys.

Mahzarin Banaji, another group member, says, "Social psychologists introduced the world to the idea that the immediate situation is hugely powerful in determining behavior, even intergroup feelings. Evolutionary theorists have made us aware of our ancestral past. In this work, we weave the two together to show the importance of both these influences at work."

Santos herself concludes that "The bad news is that the tendency to dislike outgroup members appears to be evolutionarily quite old, and therefore may be less simple to eliminate than we'd like to think. [This reinforces those who think prejudice, racism, etc., are "natural" rather than learned behaviors]. The good news, though, is that even monkeys seem to be flexible [we saw above there is no basis for this statement] about who counts as a group member. If we humans can find ways to harness this evolved flexibility, it might allow us to become an even more tolerant species [assuming we are a "tolerant" species in the first place]." Anyway, being tolerant means respecting people in other groups not just accepting them into your own--"How white of you" does not indicate tolerance.

It should be noted that if the monkeys can simply change groups when they feel like it, and be accepted, there is no "prejudice" at all going on. Before I give up the view that human prejudice is 99% cultural I want to have both a "prejudice gene" and an example of monkeys gassing each other. A friendly welcoming manner is just as likely as prejudice toward the "other"-- cf. how the Caribs welcomed Columbus, granted this was their mistake, and Squanto helped out the Pilgrims. Native Americans had to learn to dislike Europeans.

As for the Implicit Association Test, its critics charge that it lacks empirical evidence of its efficacy and that its reliability measure is low-- i.e., when the same subjects are retested they give different responses. The IAT is not therefore a really strong scientific tool to use for the claims made on the basis of its results. What is true of the IAT would follow for the Monkey IAT as well.

A final quote from a Science News article: William von Hippel a psychologist at the University of New South Wales has said, "Rarely has a methodological tool garnered such strong adherents and detractors. The IAT should be vigorously researched and debated, but we still do not really understand what it reveals.