[sojuz151]

My biggest problem is that this hypothesis does not explain why farming started so much later in the Americas than in Eurasia. From Wikipedia "approximate centres of origin of agriculture and its spread in prehistory: the Fertile Crescent (11,000 BP), the Yangtze and Yellow River basins (9,000 BP) and the Papua New Guinea Highlands (9,000–6,000 BP), Central Mexico (5,000–4,000 BP), Northern South America (5,000–4,000 BP), sub-Saharan Africa (5,000–4,000 BP, exact location unknown), eastern North America (4,000–3,000 BP). " and American civilisation were about 4 thousand years behind Eurasia when it come to technology.

[perrygeo]

The Cucurbita pepo squash was domesticated 10k years ago in the Americas. So there was absolutely small-scale "agriculture" throughout the Americas, roughly on the same timeline as Asia. In fact, they were experts at it (see the Three Sisters - one of the most brilliant sustainable agricultural technologies ever invented with no rival in Eurasia).

So Americans knew of advanced planting techniques but didn't deploy them at scale for another 6k years. Why? The population had not yet risen to the density that necessitated full-scale, crop-dependent communities. Far from being behind the technology curve, I'd interpret this as wise governance and population management to avoid resorting to a lifestyle that some viewed as a low-class labor. Why break your back toiling in the field when you can eat buffalo and fish?

[FrustratedMonky]

They be getting fat on that Buffalo. No need to farm. Just, hunting, smoking, party times.

Edit: or seriously some, maybe there wasn't a drive to need it.

[nerdponx]

Do we even have a clear sense of how densely-populated North America was 7000 years ago? Were there just not enough people? Was the climate suitable? Was it harder to domesticate American plants for agriculture than Eurasian plants? Etc. I feel like there are a lot of possible factors that could cause farming to develop late, which are unrelated to the validity or non-validity of the hypothesis.