We often tell the history of agriculture as though someone, somewhere, had a brilliant idea: instead of collecting wild plants, why not plant them?
The archaeological record tells a much stranger and more interesting story.
Agriculture emerged through thousands of years of interaction among people, plants, landscapes, animals, weeds, pests, climate and technology. Humans did not simply domesticate plants. Plants, in a very real evolutionary sense, also adapted to living with humans.
This is the central idea of plant domestication as coevolution.
Humans created a new ecological niche
Before farming, plants already formed the foundations of terrestrial food webs. Human hunter-gatherers exploited those food webs by collecting fruits, seeds, roots, tubers and nuts.
Cultivation changed the rules.
People began clearing vegetation, disturbing soil, concentrating useful plants, moving seeds, digging tubers, burning landscapes, sowing particular patches and repeatedly harvesting from them.
These activities created entirely new ecological environments.
Agricultural fields were therefore not simply places where food was produced. They were evolutionary arenas.
Crop plants benefited from human protection and dispersal. Humans benefited from increased food production. But other organisms joined the system too.
Mice ate stored grain. Weevils colonised harvests. Sparrows followed settlements. Weeds adapted to disturbed agricultural soils.
The authors describe some of these hitchhikers as “parasitic domesticoids”, organisms that evolved around the crop-human system without necessarily being intentionally domesticated.
Agriculture therefore created something closer to a new food web than a simple human-crop partnership.
Agriculture redirected ecological energy
Photosynthesis captures solar energy and converts it into plant biomass.
Agriculture increasingly redirected that primary productivity toward a narrow group of organisms:
humans, domesticated crops, livestock and organisms associated with them.
As agriculture intensified, landscapes that had supported diverse wild ecosystems increasingly channelled energy into wheat fields, rice paddies, maize plots, orchards, pasture systems and human populations.
The result was extraordinary.
Agricultural societies could support larger and often more sedentary populations. Domesticated plants expanded far beyond their ancestral ranges. Entire ecosystems were reorganised.
By several thousand years ago, these processes were already influencing landscapes at continental scales.
Humans did not invent agriculture only once
Another important implication follows.
Agriculture was not a single discovery radiating outward from one centre.
Plant domestication occurred independently in numerous regions, involving completely different plants and cultivation systems.
The Fertile Crescent produced wheat, barley and pulses.
China contributed rice, millets and soybean.
Mesoamerica saw maize, beans, squash and chilli domestication.
South America produced potatoes, quinoa and manioc.
Africa contributed sorghum, pearl millet, African rice and many other crops.
New Guinea developed agricultural systems centred partly on vegetatively propagated crops.
Different communities therefore entered agricultural relationships through different ecological doors.
Agriculture is still evolving
This perspective matters today.
Agriculture is not the endpoint of domestication. It is an ongoing ecological experiment.
Modern agriculture represents only the latest configuration of relationships that began thousands of years ago.
Understanding those older systems may therefore help us rethink future agriculture, particularly questions of crop diversity, resilience and sustainability.
The remarkable lesson is that agriculture was never simply about humans controlling nature.
Agriculture emerged because humans became deeply entangled with it.
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Further reading: This post is inspired by and draws on Dorian Q. Fuller, Tim Denham, and Robin Allaby, “Plant domestication and agricultural ecologies,” Current Biology 33, no. 11 (2023): R636–R649, doi:10.1016/j.cub.2023.04.038. Read the original article in Current Biology
For a classic and highly readable perspective on why plant domestication arose in some regions but not others, see Jared Diamond, Chapter 8, “Apples or Indians: Why Did Peoples of Some Regions Fail to Domesticate Plants?”, in Guns, Germs, and Steel: The Fates of Human Societies (W. W. Norton, 1997), pp. 131–156. Read “Apples or Indians” View Guns, Germs, and Steel on Google Books
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