Biology 202

2006 Second Web Paper

On Serendip

The theory of evolution has gone to humans' heads. Or maybe it's not the theory, but the fact that its rise to prominence "confirmed" for many what had only been suspected before: that humans were the most highly evolved species. That we humans were the real deal; the coolest kids in school. I'm thinking about those diagrams where the drawings stretch from left to right. On one side is an ape on its haunches. The final drawing on the opposite side is a loin-cloth-clad man, ready to walk right off the page. This drawing reinforces the idea that we're the pinnacle. However, we are no more the pinnacle than any of our primate friends. In fact, we have quite a lot to learn from the study of primates, a field that until recently had been dominated by strict through-processes which obscured useful and significant data about how primates think and function.

In junior high school biology class, our dour-faced teacher lowered his spectacles on his nose and reminded us that we shared 99% of our genetic material with chimpanzees. "Lucky for you, it's only 99%," he continued. Because of these genetic similarities, studies of primates such as the chimpanzee have been used as stepping stones to arrive at more general conclusions about humans and human nature. These observations and studies have, until very recently, focused almost exclusively on gender models where the male primate is seen as dominant and the female as passive. For example, this passage from a textbook on sociobiology: "These data make it clear that only males are directly involved in differential selection among rhesus [monkeys] and probably all the terrestrial and semiterrestrial primates" (1). This process of generalization prohibits more nuanced observations, both about primates, and also about the way in which primate behavior can be applied to the study of human nature.

In his article "A Natural History of Peace," neurobiology professor Robert Sapolsky works towards a more finely attuned process of observation among the primates he has studied. As he points out, "Across the roughly 150 primate species, the larger the average social group, the larger the cortex relative to the rest of the brain. The fanciest part of the brain, in other words, seems to have been sculpted to enable us to gossip and groom, cooperate and cheat, and obsess about who is mating with whom. Humans, in short, are yet another primate with an intense and rich social life..." (2). Watching primates can teach us things about human brains, such as the observation about the cortex-size of primates involved in varying social groups. However, as Sapolsky goes on to observe, once primates were discovered to be cold-blooded killers in the 1960s, and humans became one among many species to be violent (instead of the only one, as previously supposed), humans got it into their heads that they were some sort of super-evolved killer ape, "according to which we have as much chance of becoming intrinsically peaceful as we have of growing prehensile tails" (2). Sapolsky strives to use the evidence he has collected to complicate this mindset.

In the baboon group that Sapolsky observed in the 1980s, a number of interesting changes happened. A nearby tourist lodge "expanded its operations, and consequently the amount of food tossed into its garbage dump" (2). The group of baboons that lived near the garbage dump used this as their primary source of food, while the more aggressive males from Sapolsky's observation group would stage raids in order to obtain the food they wanted. When tainted meat caused an outbreak of tuberculosis, most of the group who lived near the dump died. The aggressive males who would travel to the dump from Sapolsky's group also died. His group was "left with males who were less aggressive and more social than average, and the troop had double its previous female-to-male ratio" (2). The group's dynamic changed completely, becoming more peaceful and involved in activities such as grooming and child-care. Sapolsky observed that the change was not the result of a changing gender ratio, for other groups observed in the area had similar male/female numbers but maintained the more aggressive lifestyles--it was the "demographic disaster--what evolutionary scientists term a "selective bottleneck"" (2) that had left the group with its much more social males. This utopian society preserved its fabric even with the entry of outside males: the males were indoctrinated by the group's females, and they quickly learned that this was a slightly different way of living that appealed to them. Sapolsky uses this example to draw conclusions about human nature. Though humans, as primates, are "hardwired for xenophobia..." since "Experiments have shown that when subjects are presented with a picture of someone from a different race, the amygdala--a structure in the brain associated with fear and aggression is stimulated" (2), humans who have been exposed to people of different races consistently will show no activity in the amygdala. Therefore, Sapolsky believes that there is enough flexibility in human/primate nature to accommodate different types of processing the idea of the "Other," and that this flexibility should not be written off in social activism for peace.

One other mindset that is being challenged in primate studies is that of gender. As I mentioned before, many primate studies were based on males as active and females as passive. However, this ignores the fact that there are many variances to this "rule." As Sarah Blaffer Hrdy, the author of "Raising Darwin's Consciousness," points out, "We could just as easily have focused on any number of lemur species, species in which the females rather routinely dominate males. We could have decided to make example of the shy and nocturnal owl monkey..., where males and females cooperate in child care with the male playing the major role in carrying and protecting the infant, or we could have focused on the gentle South American monkeys known as "muriqui"..., who specialize in avoiding aggressive interactions, or any of a host of other primate species in which we now know that females play an active role in social organization" (3). However, these types of primates are not generally the subject of primate studies that seek to draw conclusions about primates in particular and humans in general. In emerging studies, emphasis is being put on the agency of female primates in social situations that would have been overlooked under the old model. For example, "Female baboons... actively engage in forging for themselves a network of alliance with different males. In short, there is much more going on than simply males competing with other males" (3). If this type of expansion can continue, the definition of what it means to be a primate, a human, or a specific gender can be complicated in useful ways, direction our thoughts in new directions, towards new discoveries.

As I've pointed out, new movements in primate studies are pushing humans towards acknowledging alternative possibilities in arenas such as human nature and gender. The concept that peace could be a trait passed on through evolution is a powerful possibility. The idea that female primates could have more agency than previously supposed, and therefore if we apply the same principles to humans and attempt to shift our obscuring gender lens, that human females might as well, is also exciting. In conclusion, we do not know just how entrained our thought-processes are until they are challenged by a newer, more multifaceted approach. In this way, our thought process can evolve along with our continually changing understanding of primates, and thus, ourselves.

Sources Used:

1) D. Freedman, Human Sociobiology (New York: Free Press, 1979). pg. 33.

2) Sapolsky, Robert. "A Natural History of Peace." Harper's. April 2006, Vol. 312, No. 1871. pp 15-22.

3) Hrdy, Sarah Blaffer. "Raising Darwin's Consciousness." The Gender and Psychology Reader, ed. Clinchy & Norem. New York University Press, New York, NY. 1998.


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