The Danish economist Ester Boserup (1910–1999) advanced a clever theory for the origins of farming. The theory was that farming began in fertile river valleys (and wetlands) because the available resources led to an increase in population, and the consequent pressure on food resources drove people to adopt farming to sustain the increased population. This was part of her larger analysis of the long-term effects of rising land/labour ratios on the intensification of land use.
It is a nice clear theory, that allows for the repeated adoption of farming in about a dozen separate places around the world. It is a lovely theory, slain by the proverbial ugly fact: there is no evidence of pressure on food resources. People did not take up farming because they had eaten out alternative resources. On the contrary, the pattern suggests a long period of a mixture of foraging with a little farming on the side, until a tipping point is reached, and we then get settlements committed to agriculture, with foraging on the side.
People move from foraging (taking food from the environment) to some low-level supplementary cultivation, but still mainly foraging, to high-level cultivation, supplemented by foraging. With domestication (selective breeding crop and animal species for human convenience) being a recurring element in the transition to full-scale farming. But the evidence that there was a lack of food resources in the wider environment sufficient to sustain the population, that the transition was driven by pressure on food resources, is just not there.
I want to suggest the Boserup was right about crowding, but wrong about the issue in the transition to farming being crowding putting pressure on food resources. The issue was crowding itself: crowding as a social phenomena. The pressure that drove the transition was the presence of other humans because the food resources were so plentiful. Indeed, sufficiently plentiful that it did not encourage measures to reduce population growth because parents kept judging there was enough to feed that extra child.
The foraging-to-farming sequence in the Fertile Crescent (extending up to Southern Anatolia) is relatively clear. First, we get foragers settling down (sedentism) but still being foragers (with a diet of mainly meat and animal fat, plus some nuts and fruits). This overlaps with foragers constructing ritual centres. Then we get evidence of some small-scale cultivation (grains and legumes) as a supplementary food source. Then we get settlements committed to agriculture as their primary food source, though there is still foraging (especially for meat: they seemed to have eaten anything that flew, walked or swam). Then we get domestication of herd animals (sheep, goats, pigs and cattle). Each stage in the process takes centuries, even millennia, with some overlap. What we don’t have is evidence for serious pressure on food resources.
Foragers generally dislike crowding
The evidence is fairly clear that foragers do not like being crowded by other humans. For instance, when Homo sapiens entered the Americas, they spread southwards at a rate of about 10km a year. That is quite a fast rate of spread.
The evidence also suggests that foragers are capable, if they have a run of good seasons, of quite high rates of population growth. So, we have humans arriving in the Americas and invading a space full of untapped-by-other-humans food resources. They breed like crazy and eat (and kill off) the megafauna. Spreading to chase those disappearing megafauna and because, by foraging standards, it’s getting a bit crowded. Hence that 10km a year rate of spread.
Why would foragers not like being crowded? Women and children: specifically, their women and children.
The general human foraging pattern is relatively straightforward. Women, who are regularly going to be pregnant or having nursing infants, look after the kids and engage in the low-risk gathering (nuts, fruits, other edible plants) and hunting (e.g. lizards, small animals, etc) that you can do while minding the kids. Adult men do the high-risk hunting (large animals) and gathering (raiding beehives for honey) that you can’t do while minding the kids.
So, the result of standard foraging patterns would be that the women and children would often be separate from the men, when the men are out hunting. Having other foraging groups nearby would be enough to make everyone nervous. Hence the tendency, if they can, to move on when the local foraging space starts “filling up”. That would produce a 10km rate of spread through a new landscape quite easily.
(As an aside, the foraging pattern of men building teams based on trust-under-pressure and women building intimate connections, a pattern that continues in many agropastoralist societies, has resulted in socio-cognitive patterns you can see in any school yard: boys form teams and girls form cliques. Both are ways of connecting, but one is centred around physical risk, and use of things, and the other on emotional risk and personal interactions. The more agreeable and neurotic boys join the cliques, including those interested in learning how to attract boys. The less agreeable and neurotic girls join the teams, including those interested in learning how to attract girls. In over 20 years of presenting to schools, I have seen a lot of schoolyards.)
But suppose you are in a relatively enclosed geographical area with lots of food resources. The population starts filling up (by foraging standards) and you get somewhat “hemmed in”.
If moving stops being an option, there is another alternative. Sedentism: having a home base the women and children stick to, and that the men can spiral around when hunting. This can only work in an environment rich enough in food resources to sustain that, typically with overlapping ecosystems that provide year-round food sources, and ideally with the capacity to smoke, dry or ferment food. But if the environment is that rich in food resources, then the physical space will start producing crowding and responses to deal with the crowding.
If there are lots of food resources, but not the range to sustain foraging sedentism, then either some other mechanism would need to evolve to police boundaries, or a rather grim pattern of pre-emptive and retaliatory violence is likely to emerge. Or a mixture of both. As, of course, later became a pattern in various horticultural societies. An elevated protection problem generating warrior elites could explain the very hierarchical nature of Mesopotamian urbanisation.
So, the first response to crowding is to adopt a home base. This is a strategy that is going to work for a while. Perhaps quite a long while. Especially as sedentism probably ups the disease vulnerability, so possibly takes some of the population growth pressure off. Starting to grow some supplementary crops becomes a practical option. Doing so also lessens the need for women and children to wander.
By adopting sedentism, you are also likely to begin to evolve social mechanisms to deal with crowding within the group. But the food resources are still good, so the crowding effect of population pressure continues, though it may take a long time to trigger the next level response.
The power and use of ritual
Ritual centres, probably organised by shamanic networks, can also play a role. (Prostitutes are not the oldest profession, shaman are: the development of shamanic networks could have been a step towards the development of priesthoods.) While ritual centres constructed by foragers are not unknown (they also occur, for instance, in Mesoamerica) Göbekli Tepe is impressive in its age, scale and elevation of human imagery.
To understand the power of ritual, consider the four modes of knowledge: propositional, procedural, perspectival, participatory — knowledge that, knowledge how, knowledge of and knowledge in. (For those of a Classical Greek bent: episteme, techne, noesis, and gnosis.) Ritual engages all our modes of knowing: you ritually affirm doctrine, you perform ritual, you perceive ritual, you experience ritual. The more it engages all modes of knowing, especially from the reinforcing feedback effect of group participation, the more cognitively powerful the ritual is.
Now consider the uses of ritual. It is a shared experience of common action and participation. Ritual both signals a shared social alignment and expresses it. Moreover, regular attendance at ritual centres provides an opportunity for building connections and developing exchange networks. This would be true if one were still mobile foragers, but even more so if one has started to adopt sedentism.
Participating in common rituals is also a way to manage crowding. Indeed, constructing a ritual centre is itself a somewhat ritual-like experience, signalling and expressing common social alignment.
Fast forward a few thousand years, and we have riverine labour-service autocracies marshalling off-season farm labour to express, manifest and acknowledge the power of the ruler and control the use of “idle” labour through monumental construction. (Modern totalitarian societies are also fond of rituals of mass participation and submission, including ritual elections.) Ziggurats, pyramids, Angkor , Borobudur and similar monumental constructions are annual rituals of power expressed in stone. They are also, in a sense, ways to manage crowding: or, at least, the problems of social scale.
Sedentism to full farming
So, getting back to our crowded foragers, we have sedentism with supplementary farming. At some point, a tipping point is reached, and people shift from a few supplementary crops to a commitment to farming as their dominant plant food source, even dominant food source. Some mixture of the development of mechanisms to deal with crowding within the group, domestication increasing the productivity of crops, and the calorie-production advantage of farming, is reached, and you have become a farming culture.
People have moved, in millennia-long stages, from responding to crowding to finding ways to manage crowding. With the high level of food resources in the local area driving the crowding, and that crowding itself driving the transition to sedentism and agriculture, rather than pressure on food resources being the constraint that drives the transitions. (It is vaguely analogous to Homo becoming the apex predator via tool-using cooperation leading to an evolutionary surge in Homo cognitive development, or at least a shift in the evolutionary pressures, to cope with dealing with a cooperative, tool-using apex predator.)
Once farming is adopted, then crowding on resources is likely to become a factor, as human populations steadily increased. Hence the spread of farming and farmers out from the cradles of farming as those children the existing farm could not support then sought their own farmland.
Anatolian farmers seem to have spread across arable Europe at a rate of about 1km a year, though farming may have spread by cultural diffusion in much of Northern Europe, the Alps and west of the Black Sea. Not being urbanised, Anatolian farmers did not have the “demographic sinks” of Mesopotamian cities to absorb extra population and so they spread across much of arable Europe.
Once the arable land is filled up, Boserup’s processes for intensification of land use become a very plausible social mechanism.
Anyway, that’s my suggested mechanism for why farming developed again and again in fertile areas with lots of available food resources.
(A 15 October 2020 Monash University Archaeology Zoom seminar by Andy Fairbairn of the University of Queensland on Cultivating and foraging on Turkey’s Konya Plain from 9500–7,000 BC: insights from Pinarbasi, Boncuklu and Canhasan III was enormously helpful in providing a coherent picture of the foraging-farming transition. Prof. Fairbairn is not in any way responsible for the above hypothesising.)