Humans would be unlikely to adopt agriculture unless there were no other ways to get food. It’s dull, back-breaking work and not near as fun as hunting, trapping, fishing, or even pulling fruit and digging roots.
However, in the early stages of development, agriculture was never a choice. Tossing seeds on the ground was just one of many ways some folks found they could get some more food, so of course they did it. As the local population grew there wasn’t so much game around and the wild plant were getting over-plucked, so of course they spent more time tossing seeds, or even covering them over and watering them. It was a vicious cycle: more growing makes more food, makes more people, who eat up the wild food supply, which means you need to grow more food. Trapped, dammit.
I used to think that this was the mechanism. Now, I’m not so sure.
Looking at various prestate societies, and the recent archaeological evidence from Turkey (that monumental architecture predated agriculture), I’m starting to think that agriculture sprung from the desire to have a lot of people hanging around in one place for a long time - very difficult for hunter-gatherers to achieve (unless they live in the equivalent of Canada’s West Coast).
Why have a lot of people in one place for a long time? Perhaps ostensibly to conduct religious rituals and build up monuments (as in Turkey); perhaps this sprung, ultimately, from competitive feasting (as in New Guinea); perhaps for safety in a fight against another clan or tribe.
Lurking behind all of these is the desire on the part of some for leadership and power. A religion needs a priest. Monument-building requires direction. A feast needs a “big man” to organize. War needs leaders.
Perhaps this will to power came first, and the need to feed a lot of worshipers, feasters, or warriors all gathered in one place accellerated reliance on agriculture.
I’d be very surprised if the switch from h/g to agriculture was a conscious decision. More likely, it came about organically without anyone even knowing it was happening. Agriculturalists probably still hunted a lot and even gathered wild foods that were not domesticated in addition to growing crops.
I tend to agree with this line of thinking. Perhaps it went like this: HG group brings a few bags of fruit/grains/seed back to their camp, discard a few damaged/rotted pieces in their garbage heap, or in their latrine, and move on to the next day’s camp. They come back to the same camp next season, or next year, and see a bunch of the fruit/grain/seed plants growing nearby. They notice how much easier it is to collect the food when it is nearby their camp, stay a bit longer to enjoy the bounty. Next thing you know they stay the season, or a full year to tend and guard the “crop” from pests or other humans. Maybe throw in a few more staples, build a few more bark shanties, develop pots or other materials to now “store” some of the extra food for the later off-season. All the while supplementing their diet with wild foods from the local area, as stated upthread.
Lots of time sitting around - what to do? Hey, look at what I did with this clay! And if I twist these vine fibers together, it makes a handy stonger vine that lasts a while. What? You rub those stones together over the left-over chaff and there is a spark and fire? Maybe some great being in the sky makes the rain, the fire, the food? Hey, your sister looks mighty fine!
A few more steps in the process and we get to Facebook.
I too do not think it was a concious decision, but a more gradual process.
Agriculture no doubt emerged from “improving” the local patches of naturally occurring plants suitable for gathering. H-Gs do this all the time.
For example, wild blueberries grow in places where there has been a wildfire. A H-G may well burn off a good place for blueberries to grow, deliberately.
However, once a decision has been taken to gather a lot of people in one place deliberately for other reasons, making use of such environment-maximising tricks becomes more important, and gathering from “improved” patches becomes more significant - as everyone knows, having a lot of people in one place tends to spoil the hunting.
Naturally, people still hunted and gathered, but over time the significance of the “improved” patches became greater, and greater care was taken - instead of (say) just burning off a good place, taking care to weed it, or even to protect it from animals.
Pretty soon, instead of H-G’s “improving” naturally occuring good patches, you have agriculturalists. It’s really a matter of emphasis.
I assume it was still a major leap to go from “camp here for a few weeks while we collect what we can” to actually collecting enough to tide them over several months of fixed residence… Plus, there’s the question - what was the typical storage method? A year’s supply of food is a lot of food and an invitation for vermin (cue the domestic cat discussion).
I assume the impetus was something along the lines of “we collected way too much to carry with us, we’ll just camp here and chow down until it’s gone”. Do that too much, and you’ll find your off-season hunting ground taken by someone else.
Then there’s also the whole discussion about corralling and eventually domesticating the less difficult wild game. (Goats? Start with something small like that?)
And of course it has to be taken for granted that the ‘first known’ is likely some ways away, quite possibly thousands or tens of thousands of years away from the ‘first ever’, considering how rare it is that artifacts from prehistory come down to us.
I think the fact that agriculture, civilization, and all it’s trappings of gods, kings, god kings, even writing, appeared independently in both the Old World and the New World says a lot about humanity. I’m not sure what though.
I assume hunter gatherers would return to some location seasonally where some minor cultivation was bringing them plenty of vegetables to eat. Eventually some of them began to stay year round. Eventually the vegetables weren’t plentiful enough and when the HGs returned one season the agris threw rocks at them and told them to find their food somewhere else. Some of the HGs were smart enough to find their own farmland, or some of the agris ventured out to start new farms. Any way it happened agriculture formed the concept of property ownership, something that doesn’t work well if you’re not around all year to protect it.
As I said earlier - what’s surprising is that it appeared so quickly in the new world - which goes back to the OP’s post.
Here we have a collection of people spreading into the New World, isolating themselves from any outside influences. Best estimates are they got there 13,000 years ago or so. They came via Siberia, suggesting they did not have a lot of contact with any developing agricultural areas, probably remote and not familiar with the developing agricultural civilization; plus, by going up into a subarctic zone and then back down into a temperate and then a tropical zone, it’s unlikely any plant lore survived dozens of generations travelling through unfamiliar ecosystems.
Perhaps the only thing of value they brough were domesticated dogs? We also presume taht to get that far, they were using realtively decent watercraft - hence the suggestion they reached Chile by travelling down the coast within a thousand years or much less?
So they started cold, so to speak, and within 10,000 years or less had agriculture and permanent settlements, civilizations, etc. Which makes us wonder, per the OP question, why the original homos took 40,000 to 60,000 years to do so once they left Africa?
I hope it’s not just nitpicking to mention the Cucuteni culture near present-day Romania beginning 7500 years ago. (Cucuteni villages may have been the largest settlements in the world prior to Uruk.) By 6000 years ago there were farming communities scattered across most of Europe, including even northerly parts like Britain and Denmark.
Just to add to the WAGs on why we didn’t develop agriculture sooner:
For much of our history it appears that humans just about survived: world population was pretty small, and there is some evidence we may have barely avoided extinction.
So, we would have been spending all of our time H-Ging. We simply didn’t have time to stop and observe things; having time to pause and think began to happen after agriculture.
And also our lifestyle was likely nomadic. It’s quite a leap when the one thing you can be sure of is: stay in one place and the food runs out, to realize: Hey, let’s stay in one place so we’ll have more food!
Except most studies show that HGs are both healthier, and spend less time on the basics (food/water/shelter) than their A brothers. There was plenty of time to think, and as noted before symbolism and even megalithic structures predate agriculture.
As TriPolar mentioned though, it’s scalable. Twice the work reaps twice the reward, whereas the same isn’t true for HG.
Indeed, it really only gives us a couple of viable explanations:
Extraterrestrials happened by and spread the word to humans on the various continents that, “The secret is to bang the rocks together, guys!” or
An extraordinarily bright, nomadic, fecund and determined strain of homos rampaged out of Africa and screwed everything it could get its hands on, hung around for a generation to make sure the linguistic and invention-hungry adaptations took hold and then moved on to the next encampment, lathered them up, rinsed & repeated. And they did it quickly enough to get themselves all the way to N. America before the bridge melted.
I recall (and learned on the SDMB) that bones show some pretty healthy ancestors before the Agricultural Age. I’m not so sure about the time part though.
Occam’s Razor tells us it must be aliens. But another explanation is that agricultural arises when people stay in one place. Early Americans may have found a nice place to stay with plenty of stuff to hunt and gather year round and developed agriculture over the span of generations.
Agriculture was the first human activity for which rewards were directly proportional to effort. If you worked eighty hours a week plowing fields, your yield was twice as much as if you worked forty. Hunting and gathering isn’t like that: if you work full-time, you’ll kill off all the prey in your territory, strip the bushes bare; it’s actually counterproductive to work too hard as a hunter.
It’s also not true the agriculture led to settling down, at least not universally. Most hunter gathers have a relatively well defined territory. The few that do roam do so because the animals they’re dependent on roam. Hunter-gatherers tend stay put, because to live off the land requires knowing it intimately: which plants grow where, where the big animals come to drink, where the birds lay their eggs. It takes a lifetime to really know a territory. To move somewhere else is to throw out all that hard-won knowledge.
So farmers have more kids, because while each extra kid is a burden to a HG tribe (leading to significant rates of infanticide), each extra kid is more hands in the field to a farmer. As the farmers’ offspring grow up, they have to move on and start their own farms. This is something farmers can do which HGs can’t, because unlike HGs the techniques and knowledge a farmer uses to live off of aren’t limited to any particular area. Pretty much anywhere around the same latitude will do. Ask a farmer where his great-great-grandfather lived, and he’ll name some place far away; ask a hunter-gatherer, and he’ll say ‘right here’.