User blog comment:Nkbeeching/Eurasian Supremacy based on Geographic Luck?/@comment-32656-20120902033049/@comment-4780584-20120907002346

they were cleaner for various reasons that were based on society but dont forget that the americas didnt have a single large domesticated animal save for the llama that was isolated to the andes. Their agriculture while extensive was also isolated and not widespread, mainly due to geographic barriers and the fact that the vertical axis was a considerable disadvantage due to different climates. also the eurasian agriculture proved supirior to american ones due to greater diversity and nutrition that it gave the eurasians. Also it lacked great need to change during the domestication of the plants, while Corn for instance must have taking several thousand years to develop to what we eat today.