...that caused the apparently contemporaneous development of agriculture on opposite sides of the world?

...fresh evidence, in the form of Peruvian squash seeds, indicates that farming in the New and Old Worlds was nearly concurrent. In a paper the journal Science published last June, Tom Dillehay, an anthropological archaeologist at Vanderbilt University, revealed that the squash seeds he found in the ruins of what may have been ancient storage bins on the lower western slopes of the Andes in northern Peru are almost 10,000 years old. “I don’t want to play the early button game,” he said, “but the temporal gap between the Old and New World, in terms of a first pulse toward civilization, is beginning to close.”

Let's see if they find a monolith.

I would be tending to bet on the beginning of the current interglacial period, which ended the last ice age at about the same time. I would guess that human beings had been ready, genetically-speaking, to take the leap into agricultural civilization for some time preceding the end of the ice age, but had to wait for the climate to cooperate before they could begin to explore the advantages of farming.

No mentions of farming idea diffusion yet?

Take a look at Jared Diamond's 'Guns, Germs, and Steel'. He explains why agriculture started in some places and not others, the geographical creeping of different crops, etc... It's a pretty good read.

I pretty much agree with Peter and would speculate that climatic changes (which were global) allowed agriculture to emerge in many places as soon as it was feasible.

Modern humans are a very recent species and show surprisingly little DNA diversity between the races (when compared with older species) and therefore the idea that humans in different locations invented agriculture at the same time as climatic changes made agriculture feasible is not at all surprising.

= = =

Going forward, IF global climate change is not anthropomorphic THEN we are in a big heap of trouble because ALL human civilizations arose over the last 10,000 years during a period of abnormal climatic stability as compared with geologic time.

If global climatic change is NOT human caused then the solutions could well be far more difficult than it it were.

What climate changes would make farming suddenly possible? Wouldn't there still be temperate zone between the ice and the equator, even during the last ice age? What about on the equator?

The impetus to agriculture would, I think, be a perceived need to take more control over the food supply, which would mean people in places that didn't suffer much from global cooling wouldn't have had the drive to develop it.

Another issue that has recently been spotlighted by the media is agricultural pharming. Is this the next step in the evolution of agriculture, or is it the contaminen that will force us into a new ag direction.

Umm, they got hungry and plants are easier to run down? ;)

One of the more striking points made by Nicholas Wade in Before the Dawn was that agriculture was developed to support settlement, not the other way around; there were cities in the Middle East thousands of years before farming. I would expect, then, substantial fixed communities to predate agriculture in the Andes as well. Has anyone found any?

Shameless plug: my overwrought review of Before the Dawn, among others.

Ah, I see there's information about particularly old cities, especially Jericho (now in the Palestinian Authority). A group of people called the Natufian culture lived in the area and built the first permanent towns. One thing that is worth mentioning is that they almost had agriculture. They apparently harvested wild cereals and had plentiful plants and grains present to feed their population. I gather this practice is called "horticulture". Anyway, the theory goes that the "Younger Drayas" which was a long period of cooler, drier weather may have triggered agriculture, the idea being that the wild cereals would have lost out to shrubs. So if you wanted cereal grain to eat rather than shrubs, you would have to clear that land and plant the cereals yourself. That would be true agriculture.

I don't see that cities would have been necessary to this though (assuming generously that they existed at this time). A lot of people would have had the same decisions in front of them. Even if you don't want to live in one place all the time, you still might have a patch of territory that you cycle through over a year or two. And if you wanted cereals (or other food plants) to be there when you pass through, then you'd have to plant them or otherwise insure that the cereals survived. At some point, someone would have figured that it was easier to stay in one place than to keep moving around.

But Wade says that permanent settlements existed for five thousand years before agriculture. This makes sense if we think of the most important attribute of cities as being not their static location, but the greater information available to their inhabitants, which may be deemed to scale roughly with the square of the population -- the number of possible conversations in a group of people is C = (N * (N - 1)) / 2.

Wade does not make this point; I'm swiping the idea of the information value of cities from a Cato Journal article of ~25 years ago and the number-of-conversations equation from project management training (where it's used to emphasize that teams should be kept small).

I'm aware that this is not especially intuitive, and the idea that, say, a thousand people could live in one spot (probably no more than a few acres) that's not surrounded by farmland seems, in the absence of far better transportation technology than they in fact possessed, implausible indeed. Nonetheless, that is the conclusion of the archaeological evidence, and such settlement was accompanied by known genetic changes that influenced behavior in such a way as to allow people to coexist in such large numbers in close contact. I strongly recommend Wade's book.

Jay: The book "1491" explains that in southern Peru, there was no arable land as of 4000 BC or so. On the coast there were fishing villages and up in the mountains there were plants which could be harvested for rope. So by the miracle of trade, the coast got rope to make nets and the mountains got fish - despite there being no agriculture (or possibility of it).

Nets of course may be reused more often and longer than may last week's breadloaf, which makes "horticulture" more practical.

I wonder if the same might apply in the early Near East. They had nets, rope, and fishermen too...

Isn't there supposed to be a 10,000 BC movie coming out? Mabey that will answer this question once and for all ^_^

What about possible migration of peoples from the Mediterranean region to South America?