Most archeological and genetic evidence indicates the history of agriculture extends back 13,000-15,000 years.   In his Pulitzer Prize-winning book, Guns, Germs and Steel, Jared Diamond declares that the earliest deliberate cultivation of crops occurred on the plains that intersect the Zagros Mountains of modern-day Iran, Turkey and Iraq.  Though dryer today, this was the Fertile Crescent of southwest Asia.

What factors led humans to practice agriculture?   The answer is not as simple as “Food is needed to survive.”  This and next week’s column indicate how and why people began to raise crops and livestock.

Accumulated knowledge from several disciplines, chiefly anthropology, archeology and paleontology, suggests our earliest ancestors were highly territorial hunter-gatherers in Africa who scavenged plants and their seeds or fruits, tubers, insects, birds, eggs, fish, and the meat, bones and skins of small animals and the carcasses of larger animals, usually slain by more powerful predators.

As the clans outgrew the carrying capacity of their African territories, successive waves of early humans, such as Neanderthals, migrated into Europe and Asia in search of favorable sources of essentials for their survival—chiefly foods, garments and shelter.  Life remained uncertain for these aboriginals, as the plants and animals on which they subsisted varied in their availability.

The most recent wave of our progenitors also migrated out of Africa, about 50,000 years ago.  What is considered modern man brought greater capacities with them than preceding humans.  Their brains were larger; their language and observation skills were more refined.  They probably knew something about refining metals, which greatly improved tool-making.

These modern humans found ample plants and animals in the fertile regions of southwest Asia where the terrain was warming after the most recent glacial period.  Receding ice across Europe and Asia, and in North America as well, followed by numerous cycles of healthy grasses and manure from grazing animals, resulted in rich loam soils available for tilling and growing selected crops.

The keen observation skills of modern humans enabled them to select seeds from available grasses in the Fertile Crescent, such as wheat and barley, and from indigenous legumes, such as lentils and other pulses.  They began to collect and store the tastiest seeds with the most nutritional value.

Some seeds inadvertently fell into the soil around the living quarters of human groups and sprang into the plants they desired.   Learning to tuck seeds into moist ground, to scrape away competing plants and to select the most usable and nutritious seeds from among those they grew, benefited the community.  

This was the beginning of agriculture.  As described in next week’s column, raising livestock followed crop production.  Most importantly, domesticating animals and cultivating land to produce food, clothing and shelter allowed modern man to survive lean times, such as winter and droughts, and to proliferate faster than hunter-gatherers.  

Researchers of our origins suggest the emergence of agriculture enabled people within their agrarian communities to specialize in various tasks.  Some became tool-makers, perhaps capitalizing on information passed along by central African ancestors about how to smelt metals.

Others specialized in acquiring knowledge about medicinal plants and healing rituals, thus becoming the first medical and behavioral healthcare providers.  Some specialized in building, to become the first construction engineers.  Others became the village artists and musicians.  Still others became the leaders of religious practices, government and so forth.

Development of modern culture was facilitated by people not having to spend most of their time securing adequate food, clothing and shelter.  The systematic observation methods of early agriculturists were the basis of the scientific method.  
The need to count and calculate sufficient food, as well as to construct buildings, inspired the development of a numeral system and mathematics.  The need to record information contributed to the invention of written language.  

In order to keep clans from killing each other off, governments and judicial proceedings were devised to settle territorial disputes.  

What couldn’t be explained by logic was attributed to deities, leading to the development of religions.  Some faith communities believed God created or inspired all this.

As agricultural communities proliferated in southwest Asia, some members had to secure additional territories to raise crops and livestock.   Over successive generations they migrated into Europe, Asia, Australia and some crossed the still-ice-covered Bering Strait to settle into the western hemisphere.   

There is some evidence which suggests agriculture and human societies developed independently in eastern Asia and the Americas, but perhaps these migrants brought remnant knowledge of agricultural methods with them.  

As David Montgomery argues in his 2007 book, Dirt: The Erosion of Civilization, how we behave today is greatly due to agriculture.  He also warns if we aren’t good stewards of our lives and environments, we could contribute to our demise.

In addition to the aforementioned books by Jared Diamond and David Montgomery, I am indebted to other popular and scholarly books and articles – too numerous to list here – for the information in this article.  I have posted a bibliography on my website.

Readers can contact Dr. Rosmann at the website

By Mike Rosmann, Ph.D.

Share your thoughts. Email Dr. Rosmann at [email protected], or visit his website at  You can call him at his office in Harlan, Iowa at 712-235-6100.



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