Development of city-states etc. Accumulation and strorage of all sorts of things. Then comes the need for military to protect said things.
I’ve heard beer theorized as a precipitating factor.
“Here’s to alcohol: the cause of, and solution to, all of life’s problems.”
The History Of Beer And Why Civilization As We Know It May Have Started Because Of It
Probably just likely that someone had the idea. Sure, the idea of domesticating plants and animals seems obvious to us, but whoever was the first didn’t have the benefit of 10,000 years of history telling him or her how much better farming would provide than hunting and gathering.
It’s not like there was a single thing that happened to convert hunter-gatherers to farmers. It was probably a series of steps that gradually changed them from one to the other.
I’m not sure that there is a single cause. Each lifestyle has its benefits and drawbacks. The hunting/gathering lifestyle is a very leisurely lifestyle. Hunter/gatherers spent many fewer hours “working” (that is, hunting and/or gathering) than we do. That left more time for recreation and creativity.
Settling in agricultural communities requires a lot more work, food production (agriculture or herding) can support larger populations than hunting/gathering. Larger populations have more military strength than hunting/gathering bands.
A combination of commercial, environmental, and political factors would have created the tipping point favoring agriculture/herding at different times for different bands of people. Even now, there are some hunter/gatherer bands that haven’t yet met that tipping point.
The interesting thing is that it happened in several places without prompting about the same time. We normal modern humans (allegedly) left Africa from a very small starter population about 70,000 years ago. The people who left for Americas were from a separate sub-population from about 24,000 years ago, and from Siberia, during an ice age, so not exactly conversant in plant husbandry. yet, only a few thousand years after the concept evolved in Mesopotamia /Egypt and China - and supposedly, New Guinea - the same was being done without any cross-cultural hints in southern North America and central South America. It’s possible the concept spread from Mesopotamia to China or vice versa - although it seems a stretch.
One alleged culprit is climate change - about 10,000 years ago the ice age was ending and climates in agriculture-friendly parts of the world settled to s steady sate where crops could be reliably grown, the right combination of heat, precipitation, and convenient exploitable plant life.
It should be recognized that agriculture didn’t begin in a single place and then spread to the rest of the world. There were at least 9 separate independent origins of agriculture, and perhaps more, in very widely separated parts of the world that were not in contact with one another. Certainly the New World centers of agriculture and that in Papua New Guinea were independent of any contact with those in Asia and Africa.
It has been hypothesized that agriculture became possible only starting about 10,000 years ago, near the end of the Pleistocene, because Pleistocene climates were too variable. The earliest agriculture appears to have developed about this time both in the Fertile Crescent and South America.
Yep, what md2000 and Colibri said - climate change. More specifically, the end of the Younger Dryas and a millennia-long period of climate stability that hadn’t existed before that. Here’s a paperon it.
Here we have a couple of hundred thousand years of human existence, and then 10 minutes ago, humankind decides to make a very broad change. And at roughly the same time in wildly disparate areas of the globe.
Yes, it’s amazing just how damn *global *climate change can be…
Unless you have some … alternative mechanism in mind?
Most inventions take place over a long time, even things like steam power.
Domesticating wheat appeared to require two mutations - fragile stems and seed timing. For the first, wild wheat stems break easily, which would cause the steams (plus grains) to fall to the ground, which makes farming inconvenient. For the second, wild wheat seeds do not immediately germinate or germinate at a consistent time, instead “randomly” sprouting after they fall to the ground. This is handy if there’s a drought, but inconvenient for farming. Both of these mutations needed to occur for anything like modern farming to develop.
We have evidence that humans roasted wheat grains (which are large and protein-rich, compared to “competitors”) before they really developed farming. Of course, even with the mutation, you would need plows and manuring (requires domesticating animals) and eventually irrigation before you saw anything like medieval farms. You would need mills to grind grain and make beer, or ovens to make that into bread. And metal to slice that bread 
There are numerous “champion” foods we could grow. Some fruit require grafting to get anything particularly useful out of them, which would have required years of observation, experimentation (or luck) and duplication/spreading. Different animals were domesticated at different times as well, and only some animals are useful for domestication.
I believe farming spread so quickly because anyone who started farming saw huge population increases, and any other humans who saw this wanted to copy this. Furthermore the farmers either conquered nearby people, or simply “encroached” on their lands and turned that into farmland.
There are some theories that humans simply got too good at hunting and needed to find other sources of food.
I would suggest that the tribes in North America seemed to have never run out of hunting the massive buffalo herds well into the 19th century of the Christian era.
Seems very unlikely, since agriculture developed at different times after the local extinction of megafauna, and even in areas that didn’t have megafauna, like New Guinea.
The theory that I heard popularized in the 1980s – and I am sorry to not be in any position to give you cites either as the correctness of my memories or the correctness of what the 1980s-vintage anthros wre saying – was that roughly 10,000 years ago there were several areas marked by the following descips:
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Lots of fertile land in a handful of narrowly defined belts. Yangtze River, Mesopotamian Fertile Crescent, a few others.
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Lots of barren fucking desert surrounding fertile belt.
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Population increase to the point of exceeding the hunter-gatherer sufficient yield of the fertile areas.
They’d known about the potential for agriculture. It meant a shitload of hard work. Easier to just move on and pick what’s already growing – no brainer there, right? Until you no longer can.
Agriculture doesn’t just mean setting down and behaving like farmers. You’ve gotta defend what your’e growing from the other folks who are still living as hunter-gatherers, who don’t necessarily grok the whole “this is my land” concept.
It changes everything.
This only follows in the Old World; in the New World crop domestication started before they became sedentary.
They did hunt mammoths and mastodons to extinction.
I don’t think that hunting was the single cause for their extinction. Again, climate change played a big role.
I proposed a interesting theory (tongue in cheek) in my story Putting Down Roots. (Analog October 2013)