Editor’s note: This essay is adapted from a passage in Mark Moffett’s book, The Human Swarm: How Our Societies Arise, Thrive, and Fall (Basic Books, 2019).
A great songwriter once asked us to imagine a world without countries. Could our societies ever willingly eliminate their borders and come together as one?
All evidence indicates the dreamer John Lennon had been imagining the unattainable. Certainly, among other species, fusion of healthy societies is vanishingly rare. Chimpanzee societies, called communities, exemplify this: the only “mergers” strain that word’s meaning. Primatologist Frans de Waal tells me that captive chimps from different sources can be integrated into one community, but such a merger is a nightmare for zookeepers that requires months of careful introductions, with bloody skirmishes along the way. Meanwhile, the bonobo, an easygoing relative of the more xenophobic chimp, has an aptitude for befriending strangers. That allows individuals who have not met before to forge a new community from scratch with comparatively little fuss. Yet in both apes such arranged societies are artifacts of confinement where, with the original community lost to them, the occupants have no choice but to get along. In nature even bonobo communities that have formed tight social bonds keep their collective memberships unwaveringly separate. After a time spent socializing with their neighbors, bonobo communities go back to their own territories.
Similarly, the handful of permanent mergers recorded for wild monkeys occurred only after their troops were decimated to a few individuals, as two scientists found, for example, for vervets. The survivors, like chimps or bonobos in a wild animal park, were essentially refugees, forgoing their past societies to join another as a matter of survival. Nor, under ordinary conditions, do mergers occur among the social insects that I study: for example, combining mature colonies is rarely a part of the pin-brained ethos of ants or termites1.
The only permanent mergers I know of between intact animal societies take place in Africa’s savanna elephants, and then rarely, and just between two cores (as their groups are called) that had earlier belonged to a single core, which then parted ways. By voluntarily reconstituting their original membership, sometimes years after dividing in two, pachyderms affirm they never forget.
Otherwise, once a society has jelled so its members identify with each other as an exclusive group and so long as it stays above a sufficient head count to persevere, that society remains distinct.
Was the same true of humans, going back to our earliest days on Earth? Consider the societies of our hunter-gatherer ancestors (often called “ethnolinguistic groups”), which consisted of up to a couple thousand people scattered across a particular territory in small roving bands. The bands of an ethnolinguistic group were free to variously fission and fuse, and yet the neighboring societies stayed firmly apart, no matter how much their people had in common. At best the hunter-gatherers might rarely admit a few refugees from a decimated foreign group, or more commonly a single individual, usually through marriage.
In our species the hurdle of freely merging full societies is compounded by the unlikelihood that their members can adjust to the foreign identities of outsiders, who walk, talk, dress, and believe differently from our kind. The only examples of ready mergers in humans bring to mind the captive chimps or fugitive monkeys. Coalescent societies arise when too few members of different groups are left to subsist on their own. Coalescence was the fate of uprooted American Indians from the 1540s through the 18th century after their tribes were decimated by European warfare and disease—among the prominent examples are the Seminoles and the Creeks. The refugee populations that combined into a unit often adopted the name and much of the lifestyle of the predominant tribe in their mix, with a few allowances for the social traits of everyone else.
Taking on a foreign way of life doesn’t lead to a merger either. For example, the Fur people live on arid land in Sudan that supports little livestock. A lucky family with surplus cattle can keep their herd fed only by pulling up stakes to join what are known as the Baggara. Still, this is no change in identity. The Baggara aren’t a society by any measure; rather, the term is an Arabic word that applies to the herding lifestyle, which many different tribes in the region pursue. So though a Fur family can herd much like other Baggara, and sometimes even be respected enough by other herding tribes to be accepted as allies, they remain distinct. Even a Fur who marries into a different tribe would lack the upbringing to be mistaken for a native-born member of its people.
Despite a human capacity for cultivating foreign allies, a full melding of societies is likewise never an outcome of such partnerships. Psychologists have found that reliance between groups doesn’t reduce the value people put on their differences. The Iroquois confederacy, for example, was crucial in fighting their mutual enemies (originally other Indians, then Europeans) with each tribe tasked with defending a different border of their combined realm. Yet the independence of its six tribes was never in doubt. While such coalitions as the Iroquois (or presently the European Union) can be a source of pride, this doesn’t diminish the importance of their founding societies.
For all that, the evidence is clear that all our nations are composed of populations that originated from formerly independent societies. Indeed, any human society of more than even modest size, whether a horticultural tribe on the banks of the Amazon or a continent-sprawling empire, contains, on close inspection, not the descendants of a single human stock but mixtures of citizens that comprise today’s ethnicities and races. What’s striking is the contrast between this societal cornucopia and the relative uniformity of the societies in other species, as well as those of our ancestors living as hunter-gatherer nomads. How did diversity within human societies come to be the norm, if not through voluntary mergers?
The answer is war and domination: aggressive acquisitions of both people and their land brought different societies into one fold, something that no other species can pull off. A turning point in the growth of human societies came about in prehistory when formerly nomadic people settled down to form chiefdoms that could seize control of neighboring settlements. Greek philosopher Heraclitus was right to proclaim war to be the father of all things. In places from Rome to Japan, China to Peru, the only way a society created a civilization was to combine an explosion in its population with the expansion of its realm by force.
Of this, then, we can be reasonably sure: societies, from the conjoined bands of hunter-gatherers to great empires, never freely relinquish their sovereignty to build a still larger society2. They were instead brought together by conquests over the course of millennia. Over the generations the assorted people that came to make up those societies have learned to accommodate each other to varying degrees, if not largely forget their differences. The nations themselves may unite for their mutual benefit but nevertheless are here for good, products of a history of subjugations and power plays that remain a central part of our human legacy.
1 Exceptions include fusions of army ant colonies after one loses a queen and acacia ant colonies after fights. In termites, colony mergers have been demonstrated between colonies of some “primitive” (basal) species in which workers transform into reproductives following the death of the original queen and king. Claims of mergers for more “advanced” termites (Termitidae) are difficult to evaluate and as far as is known occur rarely if ever between mature colonies in nature.
2 Robert Carneiro originally took this point of view but later backed off it to allow for the fusion of some groups into chiefdoms. His “mergers” should be interpreted in terms of formerly sovereign groups (e.g., independent villages), often of the same society, uniting under a political umbrella to accomplish a task; however, to fully incorporate those villages into a single entity would have required power plays by a chief that amounted to a kind of subjugation.
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