Second banana’s a fruitful spot, if you’re a baboon

Everywhere one looked last weekend, the media were writing about stressed out alpha baboons, thanks to a study published in the July 15 issue of Science magazine.

For the majority of us who are not top primates, and know it, what could be more comforting than to confirm that being Numero Uno can be distinctly unhealthy?

Different media outlets selected different details and ran different expert reactions, but all of the reports played the “It’s ok to be #2” angle. After all, that’s the feel good message that makes the story news.

Never mind that the study makes no claims about “portability” to human behaviour, or that the leading experts on human stress question its applicability to our own social hierarchies. But more on that later.

Like all good behaviour studies, the new research relies on an empirical test. Scat samples of the baboons were tested for the presence of stress hormones. The tests had a large sample size and were carried out over a period of nine years. No “one-off” sampling of a handful of subjects here, a problem that has often plagued similar kinds of research.

Earlier studies, with baboons and with humans, are related but not always supportive. One study showed that the lowest-ranking baboons in a troop experienced the highest stress. This was interpreted as being a result of anxiety over both physical aggression by higher-ranking males and an uncertain social position. Another study, this time of human subjects, associated poor physical health with low socioeconomic status.

These earlier results are not consistent with the new research, which showed that alpha males had stress levels as high as did the lowest-ranking males. And the troop’s beta male, just below the alpha in rank and access to females for mating, had a dramatically lower stress level than males in the other two categories — an unanticipated result.

Inconsistency with the related research is not the only issue in play here. As always, there are differences in interpretation, concerning both what the results really say and how they may or may not be applied to our human troop equivalents.

Dr. Robert Sapolsky of Stanford, a neurobiologist and noted stress expert, was intrigued by the new results, but, as reported in the New York Times, he has doubts about the importance of the study for us:

“We’re not sort of a strict dominance hierarchy species,” Dr. Sapolsky said. Humans pick and choose among many hierarchies. A low-ranking employee, for instance, might run a youth baseball league, or be the top skydiver in his local club.

Others have pointed out that while baboon dominance in enforced by direct aggression, and while “acquired” females must be physically guarded against the advances of other males, human alphas typically enforce their dominance in less direct ways, so that their stressors are not directly comparable to those experienced by Kenyan baboons.

Still others see potential usefulness in the results, citing parallels to the higher incidence of disease and shorter life expectancy of humans who live in highly hierarchical societies, as well as the common observation of accelerated aging in U. S. presidents.

While the experts may be divided on how much we can read ourselves into the study, the wide media coverage of the results shows how tempting it is to do so. Every report pitches the story as a lesson for ourselves, whether or not that lesson is justified by the science. And this temptation to make dubious linkages often lurks behind the interpretations of comparative studies.

You may have noticed an intentional theme running through the last few articles, all of which deal, in one way or another, with the question of the reliability and applicability of behaviour studies.

The common theme of these articles is the assertion that behaviour studies which are tied to empirical tests are the most strongly grounded. This suggests that in fields like evolutionary psychology research that identifies “what” and “how” has more scientific traction than attempts to explain “why.”

We have a universal human nature, because we have a universal physiology. We share a number of hardwired capacities, such as our universal ability to learn a language and our universal tendency to learn by imitation. There can be little doubt that our external and internal senses, our perceptions and cognitions, are, in the large sense, the same for all  of us.

(It’s not my intention here to engage in the complex and contentious debate of how much innate, how much culture. That’s a subject for somebody else’s book.)

What’s much less certain is “why” our “whats” developed. Indeed, a pretty strong case can be made that our nature just happened, and just happens to work. In that view, it’s not that our abilities were intended to meet certain needs, but rather that we can do what we do because we have the tools we have with which to do it. In simple terms, maybe we don’t have a horse because we need to haul a cart; maybe we have a cart because we have a horse.

The second-ranking horse in the herd will do just fine. He may not be the strongest, or the handsomest, but he’s unlikely to drop dead of a stress-induced heart attack halfway to town.

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