One can say, tongue in cheek, that the fundamental disagreement between physical anthropology and biological anthropology is that the former holds on to the idea that there exist allopatric subspecies or geographic races in our species, while the latter would only admit clines (continuous as opposed to discrete variation). But the theory of isolation-by-distance is not under serious dispute. Neither side has challenged the theory, which is indeed one of the main signals in the data. In both population genetics theory and in empirical reality, regional populations differ more from each other if they are further away in migratory distance.
A clear implication of isolation-by-distance is that, if populations from far away are thrust together — for instance, through forced transfer to a faraway colony, say, Europe and Africa to the New World — it will make it look as if there were geographic races in man. That is, even if biological variation were smoothly-varying across the range of our whole species, recent population history could bring together, to live cheek-by-jowl, populations distinct enough such that any specimen in the wild can be classified by simple inspection. This is structurally what happens in ring species — the classical case being circumpolar herring gulls (Larus argentatus). The insistence on clinial variation does not buy nearly as much as some think.
This is just one of the paradoxes of the whole subject of race. In the American imaginary, race is largely binary (retained in theory as nonwhite, poc, bipoc, etc). Specifically, white is coded as the dominant race and black as the repressed race. This is an artifact of very recent, post-1492 colonial population history. For biological anthropology, this is far too parochial. Whether there are geographic races in our species cannot be adjudicated by the American public. (Well, antiracism can impose discipline over the language used by biological scientists, but it cannot alter the conceptual apparatus.)
What is at issue in the investigations of the scientific discourse is, above all, our phylogeny (the tree of descent) — now in the process of being established at fine-scale by molecular anthropology. One simply forgets about the question of racial taxonomy, and works directly with more compact units of breeding populations situated in space and time called paleo-demes (what traditional raciologists would’ve called microraces). The question of phylogenetic systematics sensu Hennig (1966) — getting at the tree of the descent of man — is thereby defeated in the detail. This may look like, “let’s call them this other thing”; that paleo-deme is just another label for races. But realize that this is not optional. Population genetics can no more work without populations than particle physics can without particles.
If we fully update our priors on human population history, the following conclusions are inescapable.
Hominid catastrophism is real—“pots are often people.” Demic diffusion, range expansions, population replacement and local extinctions, were far from exceptional in our deep history. In particular, global population history since 1492 is not exceptional at all, but typical of the Holocene pattern.
The theory of the Bantu expansion is now well-supported and more or less securely dated. The ancestral population of contemporary Bantu speakers in Africa today radiated out of western Africa between three and two thousand years ago; in the process admixing with and largely replacing most other paleo-demes in sub-Saharan Africa.
The general pattern of the Holocene, and perhaps earlier, is characterized by the demic diffusion of paleo-demes that underwent population explosions following economic revolutions like the domestication of cereals, yeast, cattle, horse, man and so on.
One general implication of this pattern of deep history is that the world, at the dawn of the Holocene ten thousand years ago, must’ve been crowded with many thousands of paleo-demes, perhaps with their own distinct languages, mythology and culture. Most of these historical peoples were driven into extinction; with some surviving as population isolates; most often, far away from the centers of economic innovation where they were shielded from the onslaught.
The big winners of ‘the Holocene filter’ were populations ancestral to native speakers of languages from the big language families: Indo-European, Sino-Tibetan, Niger-Congo, Afro-Asiatic, Austronesian, Dravidian, etc. These correspond to the paleo-demes that underwent adaptive radiations.
Conversely, the losers of global population history were populations ancestral to speakers of languages from families with few speakers today; speakers of language isolates; a fortiori, those that went extinct. In the following map, the lack of observations in the Africa and Eurasia is not due to a paucity of data but rather evidence of absence of the paleo-demes that were almost surely replaced by the big winners of deep history. The isolate in Europe is Basque; the one in the Bay of Bengal is the Andaman Islanders.
As a general rule, such migrations and admixtures were sex-biased. More female lineages survive from subjugated paleo-demes than male lineages, while more male lineages survive from invading demes than female lineages. Males were always much more likely to migrate to the frontier or colony, even though the source populations were almost surely patrilocal (local exogamy whereby males stay put and the females disperse to mate).
Points 1-7 should be largely familiar to readers following results from molecular anthropology in the past decade or two. Perhaps less well-recognized is the “internal” or “domestic” pattern that mimics the “external” pattern. For the Neolithic passage also corresponds to a social revolution that dramatically altered a key, often overlooked, parameter of population genetics: male reproductive variance.
Males have higher reproductive variance than females in hunter-gatherer, agrarian, and industrial demes. Indeed, this is a general pattern across animal species known as Bateman's principle. The unconditional probability of reproductive success is lower for males than females, and the intensity of sexual competition higher.
What seems to be underappreciated is that male reproductive variance exploded during the Holocene. This is evident from what is called the “post-Neolithic Y Chromosome Bottleneck.” The diversity of male lineages collapsed as social stratification destroyed the economic underpinnings of monogamy. As Chapais explained in his extraordinary monograph, Primeval Kinship, monogamy is simply “maximally constrained polygyny” that obtained under the egalitarian conditions of the Pleistocene.
Evolution has a single criterion of fitness; reproductive success. By this criterion, the evolutionary trajectory of our species was altered by the economic, social and “foreign policy” revolutions of the Holocene. Even as the Holocene revolutions “externally” stratified the many thousands of paleo-demes — sorting paleo-demes, language families, and ways of living and thinking, etc into definite winners and losers of deep history — it also sorted or stratified lineages “internally.”
It did so in two ways. Women were subjugated to men — what emerged was sexual dimorphism in power in our species — and men were subjugated by powerful men who controlled property. The structures of power that emerged in the Holocene were thus both horizontal and vertical in, as well as internal and external to, the societies undergoing adaptive radiations. At the very top of the pyramid of these systems of power were men who built empires and kept vast harems. The most successful man to ever live by this fundamental criterion is, appropriately, Genghis Khan; the likely source of some 0.5% of all male lineages estimated to exist today.
Balaresque et al. (2015) found that the Great Khan was only the tip of the iceberg. Other superelite male lineages show up in a broader survey of Y Chromosome haplogroups in Eurasia. These elite lineages contain a signal of the violent history of the late Holocene.
Although they do not note it, Balaresque et al. found confirmation of Mackinder’s ideas about a deep (pre-Columbian) pattern of Eurasian history whereby the rise of horse-based empires of the steppe repeatedly brought military pressure to bear on the settled civilizations of the Eurasian rim. Prehistorical (2100-300 BC) elite lineages are from agricultural populations of the central region; while most historical (700-1060 CE) elite lineages are from Altaic speaking, pastoral populations of the steppe. These are all known to be equestrian empires — consistent with Mackinder’s deep pattern.
These superlineages provide some context for Gregory Clark’s results on elite surnames in England and elsewhere during the past thousand years. It seems that what Clark’s signal in surnames (known to be associated with Y lineages) captures is the general pattern of male reproductive variance. Contra Clark, the pattern of differential reproductive success sorted on status cannot explain why the industrial revolution began in England (which, of course, it did not, but even if we concede that it did) or when it did (1760 or 1870), because male lineages are stratified on status in many societies other than in those that industrialized over the past century or so. The general pattern of male lineage diversity is inconsistent with lineage sorting as a predictor of modernization. For instance, even among the !Kung, big men are more likely to have families with more than one wife. One pattern that is clear is that male lineage sorting is especially pronounced among pastoralists.
If the Great Khan is merely tip of the iceberg for elite lineages, then elite lineages are the tip of the iceberg of male lineage sorting. In the US, men’s income is positively, and women’s income is negatively, associated with greater reproductive success. Moreover, this seems to be a general pattern across industrial societies.
Male reproductive variance contains a signal of the intensity of male sexual competition in the sense that greater male reproductive variance implies a higher intensity of male sexual competition.
What seems to have happened is that complex societies admitted the creation of vast systems of power run by powerful men; which resulted in a greater degree of polarization in reproductive outcomes by status because of wildly successful mate guarding by powerful men. The developments of the Holocene thereby reversed the deep family structure of our species whose arrow of history pointed towards monogamy during the vastly longer (by an order of magnitude or two) Pleistocene: polygyny suddenly became less constrained with social stratification.
A consideration of three signals of mating systems in the primate order is enough to establish that the ancestral condition for Homo sapiens is monogamy. Sexual dimorphism in our species (dotted red line) is more in line with monogamous primates; testes size in our species is far from the multimale pattern; and our group size (related to the Dunbar number and encephalization) is only approached distantly by some multimale primate societies. These three facts only make sense if humans are ancestrally monogamous; that is, polygyny became maximally constrained in the human clade.
The upshot is that H. sapiens are the only monogamous (polygyny ~ 0) primate species to live in large-scale societies. The arrow of time in deep history (polygyny → 0) was reversed by the economic, social and geopolitical revolutions of the Holocene. The hockey stick would then be the exponential articulation of this deep logic, with GDP serving as a barometer of male sexual competition, and our Beckian polycrisis perhaps better seen as the logical culmination of runaway male sexual competition in the terminal Holocene.
I get it. I wrote a book 2 years ago about how to achieve financial freedom. I constantly had to edit and rewrite it so that people who are familiar with economics, investing, and financial planning could grasp what I was saying. Are used a lot of real life examples to make the point all through the book.
I didn’t mean to offend you because I can read very complex information. I wrote a lot of work on demographics, and how that’s going to change the economies of the globe, for the next two generations or beyond. And the news is not good if the predictions are correct.
I appreciate you actually took the time to respond. Have a great week.
Lots of academic words, however, I think it makes sense in its conclusions about powerful men and the idea of monogamy versus polygamy. It’s too hard to defend and protect multiple wives, so it makes sense to just have one or two as long as you can protect them from other males. If I understood this correctly, it makes some sense. I think it would be very interesting if the author could rewrite this without all of the scientific language and put it into a much more readable and understandable format.