When was the most important event in the history of mankind?
The answer is fuzzy, but for simplicity's sake, we can place it about 10,000 years ago. That was when humanity gave up its 2 million long history of roaming from place to place, hunting and gathering, and settled down to daily toil and daily bread. Naturally, I'm speaking about the agricultural revolution, and the amazing discovery of the seed.
People must have chewed nuts and grains for a while before they realised that if they put these into the earth, a new plant would spring from it. The discovery of that miracle must have been pretty startling in itself, but an even greater event was the impact it made on humanity. Pretty much everything in our society can be traced back (with some imagination) to the discovery of agriculture. Beer, bread, bazookas; you name it.
About 12,000 years ago, when the last Ice Age ended, humanity had spread to all corners of Earth. The pre-agricultural tribes went from camp to camp, depending on season. Many of them had begun to control the seeds, by deciding where they should grow, and later harvest them. However, since they didn't stay put in one place, there was a limit to how much work they could do. Slowly, things changed. Some people stopped shifting dwellings, instead they stayed in one place all year. We don't know why they did this - maybe the Earth had become overpopulated, and there just wasn't enough room for everyone to keep shifting home. Maybe climatic changes led to less food for them to hunt and gather. Or perhaps they just fancied a change.
A few societies remained in the Eden-like state of non-agriculture. These peoples live in fringe areas, areas with a climate too hot, too cold or too dry for growing things. The Inuit people of Greenland and Northern America are one example, the pygmies in Africa another, the Aboriginals in Australia a third.
In other places, they ended up with a lifestyle somewhere in between wandering indefinitely and settling permanently. In arid zones like the Sahara or Mongolia, people would start bringing animals with them on their wanderings - great herds of cattle, sheep, or whatever. This pastoralistic lifestyle creates a buffer for leaner times when the herders can live off their animals instead of starving, themselves.
In rain forest areas in, say, India and the Amazon, tribal communities have practiced slash and burn agriculture up to our days. This is a good way of living in places with little top-soil and heavy rains, but cannot support a large number of people.
However, the living solution that eventually came to dominate the globe involved settling down in one place and staying there, tilling the earth. Being sedentary has many advantages. For instance, you can store things. Surplus food can be stored for when it's needed, you don't need to lug it around. You can also make and keep more utensils and tools, not just the bare necessities. You can build nice, protective houses and walls.
You can also work complicated constructions to improve the farmland. These implements are our best proof of when and where human cultivation began getting serious. Another helpful tool is studying pollen levels in left in the soil from that period - this will show which plants flowered in an area at that time.
These are the current core areas scientists agree agriculture started before it spread outwards - all dates approximates, of course.
Middle East, especially the Fertile Crescent, 10,000 years ago: Barley, wheat, animals
Mesoamerica, 10,000 years ago: Maize, squash
Neotropics in South America, 10,000 years ago: Manioc, squash, yams
Yangtze and Yellow River in China, 8,000 years ago: Rice, millet
Papua New Guinea, 7,000 years ago: Banana, sugar cane
Eastern Woodlands in North America, 5,000 years ago: Squash
Sahel in Africa, 4,000 years ago: Sorghum, millet
Growth leads to growth
A sedentary farming community grows much faster than a group of nomads. There are several reasons for this. First, women who breastfeed produce Prolactin, which works as a contraceptive, but only for a few hours after each feeding. Among nomads it seriously reduces the number of children born, because the mother carries and her baby at all times and feeds it regularly until it is a few years old. In a safe, fenced farming community children can be left alone at a younger age. They can also start eating adult food much earlier, because things like soup and porridge are easy to consume.
For travellers, survival of the fittest tends to mean that only people who are healthy are able to walk. Old and sick people are left behind. In a farming community, they can be cared for and given enough food without being too much of a burden. Having stores of food also prevents starvation, which helps keeping people resistant to disease.
The earth-workers had other problems in store, of course: Crops may fail, and then you have a huge problem. One or two types of food is not likely to give you all the substances you need in your diet, which the hunter-gatherers got from eating just about everything. People who live together permanently in large groups have a problem with sanitation, and are likely to fall victim of epidemics now and then. But despite these drawbacks, the world's human population began growing exponentially, a growth which still hasn't stopped.
At first, there were no great inventions to make life simpler for men and women who tended the fields. All they needed was the hoe, a simple tool that had been with them for a long time. Eventually, however, the ground was laid for new, revolutionary inventions: The plow, the wheel, writing, mathematics.
From small bands of people, humanity now found itself walled up in growing cities. Living at close quarters inevitably leads to tension, which leads to a need for rules of conduct. This is the seed to our modern laws as well as etiquette.
Being able to own more than you could carry changed a lot in the social order as well. Now wealth became the key to climb the social ladder, not strength or skill at hunting. Wealth, unlike physical abilities, can be hoarded and inherited. Social stratification, specialisation, and status symbols began developing.
As populations grew bigger, enough food had to be grown to feed them. And as more food was grown, populations grew even bigger. Agricultural methods became more sophisticated. Fields were drained and irrigated, soil turned and aerated. Meanwhile, society grew more complicated.
Private ownership inevitably leads to greed and envy. A new type of crime emerged - theft. It was strongly condemned, in fact universally scorned and punished, unlike murder, which could be allowed under certain circumstances. People who were not thieves had to establish guards and build strong walls to protect their food and goods - Jericho is the famous, first walled city that we know of.
More powerful thieves resorted to armed robbery, while the self-styled rightful owners of the lands started demanding taxes from the people who worked them. When yield from the fields grew, it was possible for a number of people to do other things. While farmers produced food for everyone, others became soldiers, administrators, artisans, artists, and priests.
The seed that changed humanity in turn became changed by humanity. Through artificial selection, humanity nurtured the plants that produced the most food for them, while making their best effort to destroy unproductive weeds. Their plants, in turn, became high yielders, but were less hardy than their wild relatives. This is even more obvious in domesticated animals, where all breeding can be controlled. In today's extreme cases, we have cows that can't walk and sheep that can't look after themselves. But their yield is fantastic.
The move that made humanity
The agricultural revolution was neither swift nor bloody. However, it was the most dramatic change in human history. We moved from small, carefree nomadic groups to civilizations that created pyramids, mass warfare, literature, and destroyed the environment in a big way.
Pretty much everything can be traced back to this revolution - at least with a little goodwill.
Bread. Enough corn, mills to grind it in, and ovens to bake the bread were necessary to make it on a regular basis. These became available only when a group of people went together to perform all the tasks required.
Beer. Although bread can be made without yeast, there can be no beer without fermentation. Fermentation needs peace and quiet to happen, which is only possible when a stationary people with surplus food set some of it aside and watch the intoxicating consequences.
Bazookas. There's really no point in making bigger and better weapons than a stick when the only reason for a war is that you don't like the neighbouring tribe. When the stakes get higher - land, gold and glory - the weapons get better, as well. I chose bazookas as an example because it sounds cool, but obviously bombs, subs and nukes are also part of this development.
Did we win, or did we lose? The agricultural revolution enabled man to do great things and horrible things. We could not have led the life we do today if it hadn't been for the agricultural revolution. On the other hand, the pre-agrarian society was simpler than ours, usually much more peaceful, and with an easier workload. We live in a stressful world - but at the same time, we are able to know about and influence the world around us to a much higher degree than anyone living in harmony with nature.