Part 2 of A Crisis in the Neolithic, by Robin Dunbar [Monotheism and the Axial Age]
The extract below is a continuation of Robin Dunbar’s Chapter 8, A Crisis in the Neolithic, displayed at Social Science Files earlier today at this link:
Monotheism and the Axial Age
It seems that the major doctrinal religions emerged in areas where population growth was high and large states were emerging, but why did these demographic conditions occur where and when they did? It is conspicuous that all the great world religions emerged within the very narrow latitudinal band of the northern subtropical zone that lies immediately above the tropics. Each of the subtropical zones occupies just 12 degrees of latitude, so the northern zone accounts for about 10 per cent of the world’s occupiable land surface. Yet fourteen of the world’s sixteen monotheistic and major state religions were founded within or on the edge of this zone. Of course, there is very little landmass south of the Tropic of Capricorn, and all the tribes that historically occupied the southern zones in all three southern continents (that is, prior to the Bantu invasions of southern Africa after AD 1400) were low-density hunter-gatherers. So it is perhaps no surprise that most of these religions originated in the northern zone. However, this still begs the question as to why this very narrow band of subtropical climate should have been responsible for so many major religions.
To answer this question, we need to take note of a more general relationship between latitude and a number of social and biological phenomena. It has been known for a long time that the tropics is a hothouse for pathogen evolution, mainly due to its equable climate, warmth and lack of severe seasonality.
If you want graphic evidence of this, you need look no further than the European cemeteries scattered across the tropics. In the eighteenth and nineteenth centuries, Europeans, who lacked natural resistance to the many local diseases, experienced life expectancies measured in months rather than years in the tropics of West Africa and South Asia. As one goes north or south towards the poles, the increasingly long, cold winters put a break on most pathogens’ ability to replicate and speciate. In effect, there is a cline of pathogen and disease prevalence that starts high on the equator and declines rapidly outside the tropics.
Diseases place such heavy pressure on human populations within the tropics that there will be strong selection for anything that reduces pathogen load. Reducing the pool of people from whom one might contract a lethal disease is largely a matter of reducing the number of people with whom one trades or intermarries. And the easiest way of doing that is to have a different religion to your neighbours. This is reflected in the fact that the number of different tribal religions per area increases, and their average number of adherents gets smaller, as a function of disease load. This is reinforced by the extent to which social attitudes increasingly favour the local community (so it becomes more collectivist and less individualist) as disease load increases. In other words, people minimize social interactions with strangers and focus their social lives around a small tribe-based community.
The tropics offer a number of features that make this circling of the wagons possible. The most important is that the growing season is usually twelve months long. This means that it is possible to have several crops over the year, allowing groups to be self-sufficient rather than having to trade with each other. Trading depends on having a common language, so this is reflected in the number of people who speak a given language. …
… When the growing season is short, as is the case at high latitudes, there are only a few widely spoken languages (that is, the same language is spoken over a very wide area); the closer you get to the equator (where the growing season is as long as it can be) the more languages there are, each spoken only by a few people in a small local area.
Notice that, as in the case of the density of religions, the relationship is exponential, with the number of languages suddenly increasing steeply once the growing season exceeds about six months – roughly equating to the edges of the tropics. At high latitudes, food is unpredictable, and survival depends on having trading networks over a wide enough area to ensure that at least one community accessible to you will be far enough away to act as a refuge from whatever disaster has befallen you. Since having a common language is crucial for negotiating trading arrangements of this kind, both the size of the language community (the number of speakers of a language) and the geographical area occupied by this language community increase proportionately. Contrast the fact that the whole of Europe, covering an area of some 4 million square miles (10 million km2) boasts a mere three dozen or so distinct languages, each covering an enormous area, with the fact that Papua New Guinea, lying just off the equator, has 850 official languages in an area of just 180,000 square miles (460,000 km2). Having the same language and the same religion ticks two of the Seven Pillars of Friendship [earlier chapter].
In effect, those living within the tropics try to isolate themselves from their neighbours not because there is any constraint on food availability but because of the increased risk of contracting novel diseases for which they have no natural immunity.
They can only do this because the growing conditions are rich and food is superabundant most of the time. The pathogen load may be low at high latitudes, but the climatic seasonality, combined with much greater year-to-year variation in climate, increases the risk that people will experience crop failure, making a wide trading network more and more advantageous the further from the equator you live.
There is an obvious trade-off here between the impact of disease and the capacity for food production. Population growth will be optimized by the difference between these two processes. At very high (that is, polar) latitudes, the environment is so poor that, historically, only hunter-gathering economies have realistically been possible, and population densities will always be low. Within the tropics, and especially near the equator, populations are constrained by disease rather than food, with population density held down by a combination of the disease burden and the socio-political fragmentation that attempts to mitigate this. Somewhere in between these two extremes, the balance will be more favourable. …
… This suggests an explanation as to why the Axial Age religions all emerged in this narrow region: the length of the growing season was still reasonable, but the disease burden was low, making the conditions perfect for rapid population growth.
This suggestion is made even more convincing when we remember that, due to climate warming, the climatic zones have moved dramatically since 2000 BC. Prior to this, the northern subtropical zone was much more luxuriant than it is now. The climate was wet and humid, and the central Sahara contained many substantial lakes and permanent rivers, with abundant fish, crocodiles and hippopotamuses, as well as a variety of land mammals (baboons, rhinos, warthogs and gazelles) that are no longer found there. To take just one example, the current northern limit of the woodland baboons’ distribution is 850 miles (1,400 km) to the south of where it was in 2000 BC. In Ancient Egypt, Thoth, the god of virility and the dead, and also the scribe to the gods who invented writing, was often represented as the hamadryas, or desert, baboon, reflecting the Egyptians’ familiarity with this spectacular species; today, the nearest populations of this unusual baboon live in northern Ethiopia, some 800 miles (1,250 km) to the south. From around 4000 BC, conditions in the Sahara began to undergo progressive drying, with the present desert conditions appear- ing around 2000 BC.
Climatically and vegetationally, the northern part of Africa and the Levant would have been able to support significant human populations during the period of the Neolithic Settlement from around 8000 BC. The conditions would have been perfect for populations to explode and start to prey on each other, free from the disease burden imposed by the tropics further south. The sudden deterioration in the climate after 4000 BC would have caused significant inter-community strife as communities competed for declining resources. They may well have found it easier to raid weaker communities so as to make up their own shortfall. There is evidence for significant population movements and a great deal of coastal raiding in the eastern Mediterranean region during this time period.
That religion may help to bolster communal cohesion and cooperation in the face of external threats of this kind is suggested by a study of more than 190 tribal or social groups drawn from ninety-seven countries. The degree of ‘religious infusion’ (the extent to which religion permeates private and public life, for example by justifying prejudice and discrimination) correlates significantly with both the extent to which the society’s worldview clashes with those of its neighbours and the extent to which they were in competition with their neighbours. Analysis of the causal relationships between these variables suggested that religion exaggerated the causal link between incompatible values and willingness to discriminate against neighbours.
It may be no accident that Hervey Peoples found that Moralizing High Gods were unusually common among pastoralists. The subtropical zones were precisely where cattle, sheep and goats (in the north), and llamas and alpacas (in the south) were first domesticated. It may, equally, be no accident that the Abrahamic religions had their origin in peoples who tended flocks and herds. Indeed, the East African Cushitic and Nilo-Hamitic tribes, most of whom are cattle herders, are also monotheistic. They originated in the Upper Nile Valley on the edge of the subtropical zone and spread southwards into Ethiopia and East Africa over the last millennium, arriving in central East Africa as recently as the mid-eighteenth century.
The evolution of all primate and human societies can best be understood as a series of glass ceilings imposed by constraints on fertility and reproduction generated by the stresses of being forced to live in close proximity. During the course of their evolution, some monkey and ape species evolved novel cognitive and behavioural strategies that enabled them to breach these glass ceilings so as to live in larger groups (mainly to allow them to occupy habitats that were more predator-risky). For primates, these solutions involved the formation of grooming-based coalitions, multilevel social systems and, in a few cases, social roles like policing.
As our human ancestors sought to evolve even larger social groups, this process necessitated finding novel means of community bonding (singing, dancing, feasting) and, once language had evolved, religion. Even so, these gave rise only to informally organized communities of 100–200 people. To allow communities to evolve significantly beyond this size required social structuring and the introduction of more organized forms of religion. Doctrinal religions effectively mark the last stage that made it possible for humans to move beyond small-scale face-to-face societies and develop the kinds of mega-polities in which we still live today.
Even though each of these stages is associated with increasingly complex secular and judicial mechanisms for maintaining law and order, in itself the religious element represents a unique strand that is distinctively human. A Moralizing High God, of the kind found in many of the world religions, seems to represent a final stage of development that appears only when the civic units are very large.
[You have now reached the end of this Social Science Files exhibit.]
[MGH: So there you have it. This chapter has explained the reasons for the emergence of organised religion. The continuing roles and further-evolving functions of religion in the remainder of history is so much embroidery and path-dependence subsequent to the initial structural forces synthesised here by R. Dunbar. On the other hand, I see nothing in this chapter that would lead one to question the original great sociological insights of the late nineteenth and early twentieth centuries. Rituals, political power dynamics, the economic incentives, and the emotional, ideological or coding utilities associated with religion each had, and maintained, their own self-perpetuating force. However, the larger underlying structural-environmental and biological drivers were those that raised pressures for joining and separating peoples — polarising them by language and belief into distinct territories and occupational zones which required a societal bonding mechanism that only differentiated religions could then supply. Some other ‘sociological’ parts of the book I find somewhat less important. But in this chapter and parts of the preceding chapters, the cognitive irrationality of religion is plainly revealed to have been ‘purposefully’ rational for the evolution of societies.]
Social Science Files will return next Weekend.
The Source of today’s exhibit has been:
Robin Dunbar, How Religion Evolved, And Why it Endures, Oxford University Press 2022
Social Science Files displays multidisciplinary writings on a great variety of topics relating to evolutions of social order from the earliest humans to the present day and future machine age.
Paul Gaugin’s The Wave (1888)