By contrast, the north–south orientation of the Americas and Africa created countless difficulties adapting crops domesticated at one latitude for use at other latitudes (and, in North America, adapting crops from one side of the Rocky Mountains to the other). Similarly, Africa was fragmented by its extreme variations in climate from north to south: crops and animals that flourished in one area never reached other areas where they could have flourished, because they could not survive the intervening environment. Europe was the ultimate beneficiary of Eurasia's east–west orientation: in the first millennium BCE, the Mediterranean areas of Europe adopted Southwestern Asia's animals, plants, and agricultural techniques; in the first millennium CE, the rest of Europe followed suit.
By contrast the north–south orientation of the Americas and Africa created countless difficulties adapting crops domesticated at one latitude for use at other latitudes (and in North America adapting crops from one side of the Rocky Mountains to the other) Similarly Africa was fragmented by its extreme variations in climate from north to south crops and animals that flourished in one area never reached other areas where they could have flourished because they could not survive the intervening environment Europe was the ultimate beneficiary of Eurasia's east–west orientation in the first millennium BCE the Mediterranean areas of Europe adopted Southwestern Asia's animals plants and agricultural techniques; in the first millennium CE the rest of Europe followed suit