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IN FEBRUARY 1910, British botanist Lilian Gibbs walked across North Borneo and climbed Mount Kinabalu, a lone white woman among 400 locals. She later wrote: “The ‘untrodden jungle’ of fiction seems to be non-existent in this country. Everywhere the forest is well worked and has been so for generations.”

What Gibbs saw was a seemingly curated tropical forest, regularly set alight by local tribes and with space carefully cleared around selected wild fruit trees, to give them room to flourish. The forest appeared to be partitioned and managed to get the most rattan canes, fibre for basketry, medicinal plants and other products. Generation after generation of people had cared for the trees, gradually shaping the forest they lived in. This wasn’t agriculture in the way we know it today but a more ancient form of cultivation, stretching back more than 10,000 years. Half a world away from the Fertile Crescent, Gibbs was witnessing a living relic of the earliest days of human farming.

In recent years, archaeologists have found signs of this “proto-farming” on nearly every continent, transforming our picture of the dawn of agriculture. Gone is the simple story of a sudden revolution in what is now the Middle East with benefits so great that it rapidly spread around the world. It turns out farming was invented many times, in many places and was rarely an instant success. In short, there was no agricultural revolution. “We’re going to have to start thinking about things in a different way,” says Tim Denham, an archaeologist at the Australian National University in Canberra.

Farming is seen as a pivotal invention in the history of humanity. Before, our ancestors roamed the landscape gathering edible fruits, seeds and plants and hunting whatever game they could find. They lived in small mobile groups that usually set up temporary homes according to the movement of the prey they hunted. Then one fine day in the Fertile Crescent, around 8000 to 10,000 years ago – or so the story goes – someone noticed sprouts growing out of seeds they had accidentally left on the ground. Over time, people learned how to grow and care for plants in order to get the most out of them. Doing this for generations gradually transformed the wild plants into rich domestic varieties, most of which we still eat today.

This accidental revolution is credited with irreversibly shaping the course of humanity. As fields began to appear on the landscape, more people could be fed. Human populations – already on the rise and stretching the resources available to hunter-gatherers – exploded. At the same time, our ancestors traded their migratory habits for sedentary settlements: these were the first villages, with adjoining fields and pastures. A steadier food supply freed up time for new tasks. Craftspeople were born: the first specialised toolmakers, farmers, carers. Complex societies began to develop, as did trade networks between villages. The rest, as they say, is history.

“They lived in small groups in shallow caves, and tended small plots along the banks of seasonal streams”

The enormous impact of farming is widely accepted, but in recent decades the story of how it all began has been completely turned on its head. For starters, while the inhabitants of the Fertile Crescent were undoubtedly some of the earliest farmers, they weren’t the only ones. Archaeologists now agree farming was independently “invented” in at least 11 regions, from Central America all the way to China (see map). Decades of digging have kicked up numerous instances of ancient proto-farming, similar to what Gibbs saw in Borneo.

Another point archaeologists are rethinking is the notion that our ancestors were forced into farming when their populations outgrew what the land could provide naturally. If humans had turned to crops out of hunger and desperation, you would expect their efforts to have intensified when the climate took a turn for the worse. In fact, archaeological sites in Asia and the Americas show that most early cultivation happened during periods of relatively stable, warm climates when wild foods would have been plentiful, says Dorian Fuller of University College London.

Nor is there much evidence that early farming coincided with overpopulation. When crops first appeared in eastern North America, for example, people were living in small, scattered settlements. “The sites are less than 10 houses and they’re not very numerous,” says Bruce Smith, an archaeologist at the Smithsonian Institution in Washington DC. “There’s no real evidence that population increase was the prime mover causing them to shift over to domesticated crops.” The earliest South American farmers also lived in the very best habitats, where resource shortages would have been least likely. Similarly, in China and the Middle East, domesticated crops appear well before dense human populations would have made foraging impractical.

Instead, Smith suggests, the first farmers appear to have been pulled into experimenting with cultivation, presumably out of curiosity rather than necessity. “These are additional food supply sources, but otherwise the subsistence system based on wild species pretty much remains unchanged,” he says. That lack of pressure would explain why so many societies kept crops as a low-intensity sideline – a hobby, almost – for so many generations. Only much later in the process would densely populated settlements have forced people to abandon wild foods in favour of near-exclusive reliance on farming.

Those first experiments most likely happened when bands of hunter-gatherers started tweaking the landscape to encourage the most productive habitats. On the islands of South-East Asia, people were burning patches of tropical forest way back during the last ice age. This created clearings where plants with edible tubers could flourish. In Borneo, ; in New Guinea, 20,000 years. We know the burns were deliberate because the charcoal they left behind peaks during wet periods, when natural fires would be less common and people would be fighting forest encroachment, says Christopher Hunt of Liverpool John Moores University, UK, who has worked in Borneo for many years.

Burnt riches

Burning forest would have paid off for hunters too, as game is easier to spot at forest edges. At Niah Cave on the northern coast of Borneo, Hunt’s colleagues have found hundreds of orang-utan bones among the remains of early hunters, suggesting forest regrowth after a burn brought the apes low enough to catch, even before the invention of blowpipes. Burning probably intensified as the last ice age gave way to the warmer, wetter Holocene beginning about 13,000 years ago. Rainfall in Borneo doubled, producing a denser forest that would have been much harder to forage without fire.

This wasn’t only happening in South-East Asia. Changing climates also pushed hunter-gatherers into landscape management in Central and South America. At the end of the last ice age, the perfect open hunting grounds of the savannahs began to give way to closed forest. By 13,000 years ago, people were burning forests during the dry season when fires would carry, says Dolores Piperno, also at the Smithsonian Institution. Researchers are now turning up evidence of similar management activities in Africa, Brazil and North America.

From burning, it is just a short step to actively nurturing favoured wild species, something that also happened soon after the end of the ice age in some places. Weeds that thrive in cultivated fields appear in the Fertile Crescent at least 13,000 years ago, for example, and New Guinea highlanders were building mounds on swampy ground to grow bananas, yams and taro about 7000 years ago. In parts of South America, traces of cultivated crops such as gourds, squash, arrowroot and avocado appear as early as 11,000 years ago, says Piperno.

Evidence suggests that these people lived in small groups, often sheltering under rock overhangs or in shallow caves, and they tended small plots along the banks of seasonal streams in addition to foraging for wild plants.

(Above) Our picture of the dawn of farming is being redrawn. Gone is the simple story of a sudden agricultural revolution in the Fertile Crescent at the end of the last ice age that spread around the world. Archaeologists now agree that farming was “invented” at least 11 times in 11 different places.

(Below) The ingredients you cook with were once separated by oceans. We now know that most went through long periods of “proto-farming” before being grown in recognisable fields and turned into the crops we still eat today. Proto-farmers would tend to wild plants, perhaps planting some in small gardens

Their early efforts wouldn’t have looked much like farming is today. “It’s better to see it as small gardens,” says Fuller. “Small, intensively managed plots on riverbanks and alluvial fans – possibly not all that important in terms of the overall calories.” Instead, Fuller thinks these gardens may have provided high-value foods, such as rice, for special occasions. “It’s like growing something for Christmas dinner instead of year-round meals,” he says.

As Gibbs discovered in Borneo, and others have seen elsewhere since, this kind of proto-farming is still practised by some hunter-gatherer tribes today. They often move every few years as local game populations are depleted, leaving behind fruit trees that their descendants may return to decades later. Hunt recalls meeting a man gathering fruit in the forest near Niah who told him he was harvesting the trees “that my grandfather planted for me”. (Sadly, as younger people abandon their traditional lifestyles, this multi-generational knowledge is rapidly being lost, says Hunt.)

Archaeologists have long assumed that this proto-farming was a short-lived predecessor to fully domesticated crops. They believed that the first farmers quickly transformed the plants’ genetic make-up by selecting traits like larger seeds and easier harvesting to produce modern domestic varieties. After all, similar selection has produced great changes in dogs within just the past few hundred years.

We’ll farm… maybe

But new archaeological sites and better techniques for recognising ancient plant remains have made it clear that crop domestication was often very slow. Through much of the Middle East, Asia and New Guinea, .

In China, for example, people began cultivating wild forms of rice on a small scale about 10,000 years ago. But physical traits associated with domesticated rice, such as larger grains that stay in the seed head instead of falling off to seed the next generation, didn’t appear until about two-and-a-half millennia later. Fully domesticated rice didn’t appear until 6000 years ago, says Fuller.

Even after crops were domesticated, there was often a lag, sometimes of thousands of years, before people began to rely on them for most of their calories. During this prolonged transition period, people often act as though they haven’t made up their mind how much to trust the newfangled agricultural technology.

The inhabitants of China’s Yangtze delta about 6900 years ago, for example, lived primarily on wild foods like acorns and water chestnuts. They also grew a small amount of partially domesticated rice, often in small depressions just a metre or two across. But Fuller has found that rice makes up only 8 per cent of plant remains in archaeological sites in the region. Three hundred years later, the use of rice had tripled, and yet . “They’re keeping their options open,” says Fuller.

The record also shows a long period of overlap in other regions, with cultures using both wild foods and domesticated crops. We know from the type of starch grains found on their teeth that , yet large-scale slash-and-burn agriculture did not begin until nearly a millennium later. In several cases – Scandinavia, for example – societies began to rely on domesticated crops, then switched back to wild foods when they couldn’t make a go of farming. And in eastern North America, Native Americans had domesticated squash, sunflowers and several other plants by about 3800 years ago, but only truly committed to agriculture about AD 900, says Smith.

“Red-faced factoid: tomatoes were first farmed in Peru or Mexico – but we still have no idea when”

Indeed, some cultures didn’t commit to domesticated crops until modern times. The highlanders of Borneo, for example, only began growing domestic rice after the second world war. Many of the indigenous crops grown by traditional New Guineans, like sago palm and some tubers, are even now only semi-domesticated at best, says Denham. One reason may be that traditional gardening hunter-gatherers use so many plants – often a different mix for each month of the year – that their crops experience very little evolutionary pressure toward domestication.

The story of agriculture, in short, is not the sudden agricultural revolution of textbooks, but rather an agricultural evolution. “The evidence is showing a much more patchwork-quilt mosaic, with different sorts of practices and different plants being used in different ways,” says Denham. “In those conditions, when agriculture emerges over time, it’s a long, drawn-out process. It’s a much more diffuse event, both in time and in space.”

That means people’s motivations for making the switch were equally complex, as crops become gradually more dominant in their lives. “If people are cultivating plots, their life is going to be oriented to those areas,” says Denham. “That would require a shift in their way of engaging with the landscape, and with each other as well. That’s really why we’re interested in it – because it’s a story about us.”

(Images top to bottom: Harry Gruyaert/Magnum Photos; Cornell Capa © International Center of Photography/Magnum Photos; Matthieu Paley/National Geographic Creative)

This article appeared in print under the headline “Quiet revolutions”