Primates, Politics and Evolution

In the March 2013 issue of National Geographic is an article by David Quammen, “The Left Bank Ape”, that discusses the differences between bonobos and chimpanzees, both are some of Homo sapiens closest cousins. The social structures and behaviors of both species ironically bear some semblance to that of their more advanced cousins (human beings).

The bonobos, in case you haven’t heard, carries a reputation as the “make love, not war” member of the ape heritage, far lustier and less bellicose than its close cousin, the chimpanzee. Modern studies of zoo populations by the Dutch-American biologist Frans de Waal and others have documented its easy, pervasive sexuality and its propensity for amicable bonding (especially among females), in contrast with chimpanzee dominance battles (especially among males) and intergroup warfare.

Bonobos are a distinct form of the chimpanzee unique to the Left Bank of the Congo River that have slightly smaller proportions than chimps.

The major distinctions between bonobos and chimps are behavioral, and the most conspicuous do involve sex. Both in captivity and in the wild, bonobos practice a remarkable diversity of sexual interactions. According to de Waal: “Whereas the chimpanzee shows little variation in the sexual act, bonobos behave as if they have read the Kama Sutra, performing every position and variation one can imagine.” For instance, they mate in the missionary position, something virtually unknown among chimpanzees. But their sexiness isn’t just about mating. Most of those variations are sociosexual, meaning that they don’t entail copulation between an adult male and an adult female during her fertile period. The range of partners include adults of the same sex, an adult with a juvenile of either sex, and two juveniles together. The range of activities include mouth-to-mouth kissing, oral sex, genital caressing by hand, penis-fencing by two males, male-on-male mounting, and genito-genital rubbing by two estrous females.

“Their social purpose seems to be communication of various sorts: expression of good will, calming of excitement, greeting, tension relief, bonding, solicitation of food sharing and reconciliation. To that list of benefits we might also add sheer pleasure and (for the juveniles) instructional play. Varied and frequent and often nonchalant, sex is a widely applied social lubricant that helps keep bonobo politics amiable. De Waal again: ‘The chimpanzee resolves sexual issues with power, the bonobo resolves power with sex’.”

“Sexiness isn’t the only big difference between bonobos and chimps, though it’s probably linked to other differences, either as cause or as effect. Females, not males, hold the highest social rankings, which they seem to achieve by affable social networking…rather than by forming temporary alliances and fighting as male chimpanzees do. Bonobo communities don’t wage violent wars against other bonobo communities adjacent to their territory.”

Bonobos do share one distinction with chimpanzees. Together they are the two closest living relatives of Homo sapiens. Back almost seven million years ago, somewhere in the forest of equatorial Africa, lived a kind of proto-ape that was both their direct ancestor and ours. Then our lineage diverged from theirs, and be about 900,000 years ago, these two apes had diverged from each other. No one knows whether their last shared ancestor resembled a chimp, in anatomy and behavior, or a bonobo—but solving that uncertainty might say something about human origins too. Do we come from a long line of peace-loving, sex happy, and female-dominant apes, or from a natural heritage of warfare, infanticide, and male dominance?

On the right bank of the Congo River where gorillas and chimps shared the forest the gorillas ate mainly herby vegetation and chimps ate a diet of mainly fruit, tree leaves and meat occasionally. On the left bank bonobos which did not share territory with gorillas lived on the richer chimpanzee diet when available and sustained itself with a diet similar to gorillas when it was not. The relative stability of foraging groups within a larger bonobo community means that vulnerable individuals usually have allies present at any given moment. This tends to dampen dominance battles and fighting. According to anthropologist Richard Wrangham of Harvard, “specifically, females have other females as well as males available to protect them from those that might want to bully them.”

In conclusion, I found the National Geographic article to have similar parallels to what Americans know as the left and as the right in America. Traits common among the left include females share power, conflicts are resolved with sex and strong female bonding occurs. Traits that the right exhibits include that males share power, conflicts are settled violently and there are strong male coalitions.

Have we reached an evolutionary stage in development among Homo sapiens as the political ideology between the Left and the Right widens? Will these differences in political ideology result in the evolution of a new improved sub-species? Will there be a parallel between how gorillas, chimpanzees and bonobos evolved and how humans evolved from Neanderthals to Cro-Magnons and whatever we will become?

I am merely a lay person with no background in anthropology or sociology, but after reading the National Geographic article I’m interested in what others might think.