Read Shadows of Forgotten Ancestors Online
Authors: Carl Sagan,Ann Druyan
Perhaps no order of mammals presents us with
so extraordinary a series of gradations as this
[step by step, from humans to apes to monkeys
to lemurs]—leading us insensibly from the
crown and summit of the animal creation down
to creatures, from which there is but a step, as
it seems, to the lowest, smallest, and least
intelligent of the placental Mammalia. It is as if
nature herself had foreseen the arrogance
of man, and with Roman severity had provided
that his intellect, by its very triumphs, should
call into prominence the slaves, admonishing
the conqueror that he is but dust.
T. H. HUXLEY
Evidence as to Mans Place in Nature
1
T
he Archbishop of York is Primate of England. The Archbishop of Armagh is Primate of Ireland. The Archbishop of Warsaw is Primate of Poland. The Pope is Primate of Italy. The Archbishop of Canterbury is Primate of the planet, at least as far as his Anglican communicants are concerned. These ancient titles come from the medieval Latin word
primus
, which in turn derives from older Latin words meaning “principal” and “first.” The ecclesiastic use was straightforward: A primate of a region was the chief (“first”) of all its bishops. In recent centuries the title has devolved often to little more than an honorific. Other titles have taken precedence. But “Prime Minister” and “President” and “Premier” come from similar linguistic roots, all meaning “first.”
When Linnaeus was drawing up the family tree of life on Earth he was, as we’ve noted, afraid to include humans among the apes. But despite widespread opposition, it was impossible to deny some deep connections of monkeys, apes, and humans.
*
So all were classified into the order (for him, one taxon higher than genus) that he called primates. Scientists who study non-human primates—of course, they’re all primates themselves—are called primatologists.
This other meaning of “primate” also derives from the Latin for “first.” It’s hard to see by what standard a squirrel monkey, say, could be considered “first” among the lifeforms of Earth. But if a case is made that humans are “first,” then the tarsiers, bushbabies, mandrills, marmosets, sifakas, aye-ayes, mouse lemurs, pottos, lorises, spider monkeys, titis, and all the rest are dragged in along with us. We’re “first.” They’re our close relatives. So they, in some sense, must be “first” also—an undemonstrated and suspect conclusion in a biological
world that runs from virus to great whale. Perhaps, instead, the argument goes the other way, and the humble status of most members of the primate tribe casts doubts on the lofty title we have appropriated to ourselves. It would make things so much easier for our self-esteem if those other primates weren’t—anatomically, physiologically, genetically, and in their individual and social behavior—so much like us.
Surely there is at least a hint in the word “primate,” not just of self-congratulation, but of the idea, fully realized in the practices of our own time, that we humans arrogate command and control of all life on Earth into our own hands. Not
primus inter pares
, first among equals, but just plain
primus
. We’ve found it convenient, even reassuring, to believe that life on Earth is a vast dominance hierarchy—sometimes called “The Great Chain of Being”—with us as the alphas. Sometimes we claim that it wasn’t our idea, that we were commanded by a Higher Power, the most Alpha of Alphas, to take over. Naturally, we had no choice but to obey.
About two hundred species of primates are known. Conceivably, in the quickly dwindling tropical rainforest another species or two—nocturnal or elegantly camouflaged—may have so far escaped our notice. There are about as many species of primates as there are nations on Earth. And like the nations, they have their different customs and traditions, which we sample in this chapter.
——
Take the baboons—“the people who sit on their heels,” as the !Kung San people of the Kalahari Desert respectfully call them. Hamadryas baboons are different from savanna baboons (from whom they diverged perhaps 300,000 years ago), and free baboons behave very differently from baboons crowded together in zoos (the latter “insolently lascivious,” as an eighteenth-century naturalist described them). One telltale trait they all have in common: Sharing meat is virtually unknown among baboon males of either species, although it’s fairly widespread among the chimps.
At sunrise the baboons rouse themselves from their sleeping cliffs and break up into a number of smaller groups. Each group wends its separate way over the savanna, foraging, scampering, playing, intimidating, mating—all in a day’s work. But at the end of the day, all the groups converge on the same distant waterhole, and it may be a different
waterhole on different days. How do the groups, out of sight of one another for most of the day, know to wind up at the same waterhole? Have the leaders negotiated the matter as the sun was rising over the sleeping cliffs?
Adult male hamadryas baboons are almost twice as large as the females. They display a leonine mane, enormous, almost fanglike canine teeth, and a ruthless character. These males were deified by the ancient Egyptians. They utter deep and prolonged grunts as they copulate. Their faces are “the color of raw beef steak—as different from the mousey grey-brown females as if they belonged to two different species.”
2
As females approach sexual maturity, they are chosen by particular males and herded into harems. Squabbling among competing males over ownership of the females may have to be worked out. A high priority of the males is maintaining and improving their status in the dominance hierarchy.
Hamadryas harems characteristically comprise from one to ten females; the males are concerned to keep peace among the females and to make sure that they do not so much as glance at another male. This is a bondage with little hope of escape. A female must follow her male about for the rest of her days. She must be sexually submissive: the least reluctance and she is bitten in the neck. It is not unknown for a hamadryas female to have her skull punctured and crushed in the massive jaws of the male for a minor infraction of the behavioral code he ruthlessly enforces.
3
Conflict and tension around her are high when she’s ovulating, and somewhat muted when she’s pregnant or nursing the young. Unlike the chimps, you can see sexual coercion in the very posture of the baboon copulatory style: The male typically grasps the female’s ankles with his prehensile feet while mating, guaranteeing that she cannot run away. Compared to hamadryas behavioral norms, chimps live in an almost feminist society.
In a quarrel among females, one will sometimes threaten her rival with her teeth and forearms and, at the same time, alluringly present her rump to the male; with this postural offer of a deal, she sometimes induces him to attack her adversary. Subordinate male savanna baboons, as well as barbary apes, may use an infant—an unrelated infant, a bystander infant, or maybe an infant he is baby-sitting—as a hostage or shield or placatory object when approaching a high-ranking male. This tends to calm the alpha down if he’s in a grumpy mood.
The hamadryas male’s larger size and ferocious temperament doubtless are useful when the troop is imperilled by predators, or in conflict with other groups. But, as in the rest of the animal kingdom, when there are conspicuous differences in stature between the sexes (usually, it’s the males who are bigger), there’s exploitation and abuse of the smaller and weaker (usually the females).
*
Another distinction of the hamadryas baboons is that, alone among nonhuman primates so far as we know, two groups have been observed to ally themselves in combat against a third.
4
Among savanna baboons, where the size difference between the sexes is not so striking, there are no harems. They are great walkers; it’s not unknown for a troop to cover twenty miles a day. Unlike chimps and hamadryas baboons, here it’s the male who leaves the natal troop around puberty—again, probably as an evolutionary device to avoid incest, and genetically to connect semi-isolated populations. When he attempts to enter a new troop, objections are likely to be raised by the resident males. Acceptance by the group often requires the time-honored method of submission, bluff, coercion, and alliance-making in the male hierarchy. But in many cases another strategy works well: make friends with a particular female in the troop and her children. He grooms her. He baby-sits and cares for her young. No killing off the young here in order to bring her into ovulation, as with rats and lions. If all goes well, she sponsors his entry into the troop. We can imagine a certain exhilaration as, gingerly, he attempts to enter the new community, his gaffes and old enemies left behind, a clean slate before him, and success dependent almost entirely on his social skills.
The males are more flighty and tempestuous than the females. Social stability is mainly provided on the female side. Indeed, since savanna baboon males are transients, the only hope for coherent group structure lies with the females. In all things, female baboons are comparatively conservative; it is the testosterone-pumped males who take the risks.
The female dominance hierarchy is largely hereditary. Daughters
of alpha females are given unusual deference, even as juveniles, and have a good chance of achieving alpha status when they grow up. Every close relative of the dominant female may outrank every other member of the troop—a royal family. Submission and dominance in the female hierarchy of savanna baboons and many other monkey species is conveyed in the time-honored idiom of presenting and mounting, the heterosexual metaphor again adapted to another purpose.
——
For reasons not fully understood but worth speculating on, much more attention—at least in public discussion and until recently—has been given to hamadryas baboons than to their savanna cousins. Sometimes the impression has been left that hamadryas behavior is representative of all nonhuman primates, or even all primates. For example, the hamadryas males, in a species in which nothing else is owned, have a clear sense of females as private property. But this is by no means true of all primates. The hamadryas baboons, it turns out, provide perhaps the most extreme example of hierarchy and brutality in the entire order of the primates. This behavior was especially marked under a set of cruel circumstances devised by humans who meant them no harm:
Living with apes or monkeys in the wild did not much appeal to primatologists until recently. More typical was an expedition back to his native South Africa by Solly Zuckerman, anatomist to the Zoological Society of London:
On the 4th of May, 1930, I succeeded in collecting on a farm near Grahamstown in the Eastern Province twelve adult females from one troop of baboons. Four of these were non-pregnant. Five were pregnant; one had an embryo 2.5 mm. in length; another one of 16.5 mm.; the third one of 19 mm.; the fourth one of 65 mm.; and the fifth an apparently full term male foetus with a crown-rump length of 230 mm. Three were lactating, and their babies were caught alive. One infant was estimated to be four months old, and the other two were each about two months.
5
He dutifully noted how much fresh semen there was at various depths within the reproductive tracts of his female victims; “collected,” it
turns out, is a euphemism for “killed.” Baboons had been officially declared “vermin” in South Africa, because they’re smart enough to defeat the efforts of farmers to safeguard their crops. A bounty was paid for each dead baboon. So a few baboons “collected” for science hardly mattered, compared with the wholesale slaughter being organized by the farmers. Through such studies Zuckerman “had the luck to discover from post-mortem study that ovulation in mature females occurs in the middle of the monthly sexual cycle.”
6
The corresponding discovery about the human menstrual cycle was made around the same time.
He had long been interested in the standing of humans among the primates, and was dissecting baboons in South Africa while still a teenager.
7
But he was not wholly unmoved by the plight of the hunted baboons, and later quoted this early-twentieth-century account:
Hugging her baby tight to her breast, she regarded us with a world of sadness in her eyes, and with a gasp and shudder she died. We forgot for the moment that she was but a monkey, for her actions and expression were so human, that we felt we had committed a crime. Muttering an oath, my friend turned and walked rapidly off, vowing that this was the last time he would shoot a monkey. “It isn’t sport, it’s downright murder,” he declared, and I fervently agreed with him.
8
If you wanted to meet a baboon—and you lived in a country where they didn’t roam about in the wild—you could always go to the local zoo and see the bedraggled and deracinated inmates, lifers pent up in tiny cubicles. After World War I, some European zoos thought it would be better, as well as more “humane,” if a large number of baboons could be gathered together in a partly open enclosure admitting observation by city-bound primatologists. The London Zoo was among them, and Dr. Zuckerman was playing a central role in the organization of one of these multiyear experiments: