Monthly Archives: September 2009

Humans and men: there are differences

The tendency to equate men with humankind is an old one, evidenced by little things like the age-old icon of evolution seen here:

declaration-evolution

Bob McDonald, on his CBC show Quirks and Quarks, did a masterful job of talking about humankind without ever mentioning or speaking to a woman on his August 22nd “best of” show, which was a re-broadcast of his show from April 25th, 2009 (available in full here). In attempting to answer the question “Are we inherently violent, or are we a naturally peaceful creature trapped in a violent culture?” Mr. McDonald, not surprisingly, seeks out academic sources who support the former option.

The first person he talks to is Dr. Richard Wrangham, professor of “biological anthropology” at Harvard University and coauthor of the book Demonic Males: Apes and the Origins of Human Violence. Dr. Wrangham describes to Mr. McDonald the incident in chimpanzee research that led to the idea that chimpanzees may be inherently violent; prior to 1974, the bulk of chimpanzee observation, primarily constituted by Jane Goodall’s work with the Gombe chimpanzees in Tanzania, had revealed that chimpanzees are only mildly violent, with most altercations being only minor (with the exception of one incident in which they stole and killed a human baby). In 1974, a group of chimpanzees was observed to silently approach a male member of a neighbouring chimpanzee community and then ambush and brutally kill him.  Since then, the same behaviour has been observed a number of times, and is in fact featured prominently in the popular BBC series Planet Earth. Prof. Wrangham explains that this behaviour is evolved as a way for groups of chimpanzees to expand their territory so as to have more resources to support more children.

The second person Mr. McDonald speaks with is Dr. David Carrier, a comparative physiologist at the University of Utah. Dr. Carrier points out that there is an energy cost to bipedalism, which suggests that there must be some evolutionary advantage to standing upright. This advantage is the ability of bipeds to use their forelimbs as weapons. Dr. Carrier rejects the notion that there might be other uses for one’s forelimbs that might offset the mechanical disadvantage of being two-legged, based on the two facts that a) Australopithecines had short legs, which would have given them a stabler base for hand-to-hand combat, and b) human hands are better-proportioned for forming fists than those of any other primates. [He really said this! I recommend to Dr. Carrier that he punch someone, and see how well-evolved his  metacarpals are.]

The third person invited on the show is Dr. Aaron Sell, an evolutionary psychologist from UC Santa Barbara. Dr. Sell did an experiement where he took male participants to the gym and had them lift weights to determine their level of strength, then they photographed the participants’ faces and had other participants look at the photos to see how well they could judge the strength of these people by their looks. As it turns out, “at least with men,” people were generally able to determine the strength of a person by looking at their face. Dr. Sell suggests that facial structures such as the brow and the jawbone are determined by testosterone, which is the same hormone that makes men big and strong; thus, men with low brows and big jawbones are more likely to be strong. That’s why, when someone makes an angry face, the muscles they use tend to accentuate the brow and the jawbone.

The fourth and final guest on the show is Dr. Craig Kennedy, a neuroscientist at Vanderbilt University in Nashville. He noticed that trained male mice are able to learn a complex task (in this case, pushing a button) in order to get the chance at fighting with another male mouse. The same mice, with their dopamine receptors disabled, do not exhibit the same behaviour; this suggests that the mice’s brains release dopamine – the “pleasure chemical” – when they experience aggression. Dr. Kennedy wanted to see if humans were the same way, so he designed an experiment that involved young men watching things such as hockey fights and scantily clad young women. He found that watching a hockey fight and ogling a scantily clad woman had similar effects on the dopamine receptors in these men’s brains, thus supporting the hypothesis that watching violence is pleasurable. [He conventiently declined to remark on the effects of partaking in violence.]

Although they all have their flaws and quirks, these particular experiments and hypotheses are not what I have a problem with. I have a problem with the fact that Bob McDonald had four men on his show and used their observations about male behaviour as grounds for the conclusion that “humans are inherently violent.” It shouldn’t take a university degree to notice that the guests on Quirks and Quarks were only talking about half of humankind. Using evidence from a small and non-representative sample to make conclusions about a whole population is known in philosophy as a hasty generalization, the bane of inductive reasoning. It’s a scientists job to avoid making generalizations by using as representative a sample as  possible; with the exception of Dr. Carrier, who appears to have his own set of problems, all of these scientists do their job very poorly in this regard, as does Mr. McDonald.

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