GUNS, GERMS AND STEEL - Cloverport Independent Schools

HEMISPHERES COLLIDING • 3 6 7
deserve mention. Food production never diffused from the U.S. Southwest
and Mississippi Valley to the modern American breadbaskets of California
and Oregon, where Native American societies remained hunter-gatherers
merely because they lacked appropriate domesticates. The llama, guinea
pig, and potato of the Andean highlands never reached the Mexican highlands,
so Mesoamerica and North America remained without domestic
mammals except for dogs. Conversely, the domestic sunflower of the eastern
United States never reached Mesoamerica, and the domestic turkey of
Mesoamerica never made it to South America or the eastern United States.
Mesoamerican corn and beans took 3,000 and 4,000 years, respectively,
to cover the 700 miles from Mexico's farmlands to the eastern U.S. farmlands.
After corn's arrival in the eastern United States, seven centuries
more passed before the development of a corn variety productive in North
American climates triggered the Mississippian emergence. Corn, beans,
and squash may have taken several thousand years to spread from Mesoamerica
to the U.S. Southwest. While Fertile Crescent crops spread west
and east sufficiently fast to preempt independent domestication of the
same species or else domestication of closely related species elsewhere, the
barriers within the Americas gave rise to many such parallel domestications
of crops.
As striking as these effects of barriers on crop and livestock diffusion
are the effects on other features of human societies. Alphabets of ultimately
eastern Mediterranean origin spread throughout all complex societies
of Eurasia, from England to Indonesia, except for areas of East Asia
where derivatives of the Chinese writing system took hold. In contrast, the
New World's sole writing systems, those of Mesoamerica, never spread to
the complex Andean and eastern U.S. societies that might have adopted
them. The wheels invented in Mesoamerica as parts of toys never met the
llamas domesticated in the Andes, to generate wheeled transport for the
New World. From east to west in the Old World, the Macedonian Empire
and the Roman Empire both spanned 3,000 miles, the Mongol Empire
6,000 miles. But the empires and states of Mesoamerica had no political
relations with, and apparently never even heard of, the chiefdoms of the
eastern United States 700 miles to the north or the empires and states of
the Andes 1,200 miles to the south.
The greater geographic fragmentation of the Americas compared with
Eurasia is also reflected in distributions of languages. Linguists agree in
grouping all but a few Eurasian languages into about a dozen language