Was agriculture the greatest blunder in human history?

Was agriculture the greatest blunder in human history?
Rice famers near Siem Reap, Cambodia. Credit: Darren Curnoe, Author provided

Twelve thousand years ago everybody lived as hunters and gatherers. But by 5,000 years ago most people lived as farmers.

This brief period marked the biggest shift ever in with unparalleled changes in diet, culture and technology, as well as social, economic and political organisation, and even the patterns of disease suffered.

While there were upsides and downsides to the invention of agriculture, was it the greatest blunder in human history? Three decades ago Jarred Diamond thought so, but was he right?

Agriculture developed worldwide within a single and narrow window of time: between about 12,000 and 5,000 years ago. But as it happens it wasn't invented just once but actually originated at least seven times, and perhaps 11 times, and quite independently, as far as we know.

Farming was invented in places like the Fertile Crescent of the Middle East, the Yangzi and Yellow River Basins of China, the New Guinea highlands, in the Eastern USA, Central Mexico and South America, and in sub-Saharan Africa.

And while its impacts were tremendous for people living in places like the Middle East or China, its impacts would have been very different for the of New Guinea.

The reasons why people took up farming in the first place remain elusive, but dramatic changes in the planet's climate during the last Ice Age—from around 20,000 years ago until 11,600 years ago—seem to have played a major role in its beginnings.

The invention of agriculture thousands of years ago led to the domestication of today's major food crops like wheat, rice, barley, millet and maize, legumes like lentils and beans, sweet potato and taro, and animals like sheep, cattle, goats, pigs, alpacas and chickens.

It also dramatically increased the human carrying capacity of the planet. But in the process the environment was dramatically transformed. What started as modest clearings gave way to fields, with forests felled and vast tracts of land turned over to growing crops and raising animals.

In most places the health of early farmers was much poorer than their hunter-gatherer ancestors because of the narrower range of foods they consumed alongside of widespread dietary deficiencies.

At archaeological sites like Abu Hereyra in Syria, for example, the changes in diet accompanying the move away from hunting and gathering are clearly recorded. The diet of Abu Hereyra's occupants dropped from more than 150 wild plants consumed as hunter-gatherers to just a handful of crops as farmers.

In the Americas, where maize was domesticated and heavily relied upon as a staple crop, iron absorption was consequently low and dramatically increased the incidence of anaemia. While a rice based diet, the main staple of early farmers in southern China, was deficient in protein and inhibited vitamin A absorption.

There was a sudden increase in the number of signalling a marked shift in population. While maternal and infant mortality increased, female fertility rose with farming, the fuel in the engine of population growth.

The planet had supported roughly 8 million people when we were only hunter-gatherers. But the population exploded with the invention of agriculture climbing to 100 million people by 5,000 years ago, and reaching 7 billion people today.

People began to build settlements covering more than ten hectares - the size of ten rugby fields - which were permanently occupied. Early towns housed up to ten thousand people within rectangular stone houses with doors on their roofs at like Çatalhöyük in Turkey.

By way of comparison, traditional hunting and gathering communities were small, perhaps up to 50 or 60 people.

Crowded conditions in these new settlements, human waste, animal handling and pest species attracted to them led to increased illness and the rapid spread of infectious disease.

Today, around 75% of infectious diseases suffered by humans are zoonoses, ones obtained from or more often shared with domestic animals. Some common examples include influenza, the common cold, various parasites like tapeworms and highly infectious diseases that decimated millions of people in the past such as bubonic plague, tuberculosis, typhoid and measles.

In response, dramatically sculpted the genome of these early farmers. The genes for immunity are over-represented in terms of the evidence for natural selection and most of the changes can be timed to the adoption of farming. And geneticists suggest that 85% of the disease-causing gene variants among contemporary populations arose alongside the rise and spread of agriculture.

In the past, humans could only tolerate lactose during childhood, but with the domestication of dairy cows natural selection provided northern European farmers and pastoralist populations in Africa and West Asia the lactase gene. It's almost completely absent elsewhere in the world and it allowed adults to tolerate lactose for the first time.

Starch consumption is also feature of agricultural societies and some hunter-gatherers living in arid environments. The amylase genes, which increase people's ability to digest starch in their diet, were also subject to strong natural selection and increased dramatically in number with the advent of farming.

Another surprising change seen in the skeletons of early farmers is a smaller skull especially the bones of the face. Palaeolithic hunter-gatherers had larger skulls due to their more mobile and active lifestyle including a diet which required much more chewing.

Smaller faces affected oral health because human teeth didn't reduce proportionately to the smaller jaw, so dental crowding ensued. This led to increased dental disease along with extra cavities from a starchy diet.

Living in densely populated villages and towns created for the first time in human history private living spaces where people no longer shared their food or possessions with their community.

These changes dramatically shaped people's attitudes to material goods and wealth. Prestige items became highly sought after as hallmarks of power. And with larger populations came growing social and economic complexity and inequality and, naturally, increasing warfare.

Inequalities of wealth and status cemented the rise of hierarchical societies—first chiefdoms then hereditary lineages which ruled over the rapidly growing human settlements.

Eventually they expanded to form large cities, and then empires, with vast areas of land taken by force with armies under the control of emperors or kings and queens.

This inherited power was the foundation of the 'great' civilisations that developed across the ancient world and into the modern era with its colonial legacies that are still very much with us today.

No doubt the bad well and truly outweighs all the good that came from the invention of farming all those millennia ago. Jarred Diamond was right, the invention of agriculture was without doubt the biggest blunder in human history. But we're stuck with it, and with so many mouths to feed today we have to make it work better than ever. For the future of humankind and the planet.


Explore further

Why did hunter-gatherers first begin farming?

Provided by The Conversation

This article was originally published on The Conversation. Read the original article.The Conversation

Citation: Was agriculture the greatest blunder in human history? (2017, October 18) retrieved 14 October 2019 from https://phys.org/news/2017-10-agriculture-greatest-blunder-human-history.html
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.
74 shares

Feedback to editors

User comments

Oct 18, 2017
We could never have had the time to figure out advances like iron, ceramics or writing without first having large groups of people freed from having to gather their own food each day. The change from fighting the environment to survive to fighting other humans has also driven the advancement of technology. Now we have to figure out how to minimize our impact on the environment while maintaining or improving our nutritional intake. Ideally we will solve the problems of space travel, colonization of asteroids and moons while allowing earth to restore its balance through advances in genetic manipulation to give us plants that grow all of the nutritional needs while recycling our waste in as small a space as possible.

Oct 18, 2017
This assumption is based on the Smithsonian/Mainstream timeline of ape to human 4M years ago in Tanganyika/Ethiopia.. that then went on 10s of 1000s of miles walkabout to magically become Chinese, Scandinavian, Syrian, Inidan, etc with different body proportions etc. The original ape/ape mix needed to evolve an extra vertebra to walk upright, stop panting and start sweating, lose 50% of muscle strength and change hair location, but still we see chimps and gorillas.. strange.

For answers one needs to be open-minded, go outside the box, and open The Pleiadian Mission by US psychologist R Winters based on www.theyfly.com. One learns that Humankind in this Dern Universe is app. 100 billion years old, that the races on this Planet come from the 4 corners of our Universe. That in Milky Way Galaxy alone, billions of Planets are inhabited by intelligent humans and other life forms. That in recent times we came to colonize here 22million years ago.

Oct 23, 2017
Ethnographic studies show that among surviving hunter-gatherers (mostly foraging pattern economies) individuals have (had) significantly more free time than any later social form. What agriculture presented was the surplus that permitted non-agriculturalists a chance to specialize in very narrow focus. Also other humans are a definite part of the environment. Thinking otherwise is to assume a privilege that is illusory. The same error is made repeatedly by creationists who think human selection is not natural selection.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more