GUNS, GERMS AND STEEL - Cloverport Independent Schools

1 3 6 • GUNS, GERMS, AND STEEL
successive layers of the archaeological record; and the approximate place
and time of domestication are known. I don't deny that other areas, notably
China, also had advantages as early sites of domestication, but those
advantages and the resulting development of crops can be specified in
much more detail for the Fertile Crescent.
One advantage of the Fertile Crescent is that it lies within a zone of socalled
Mediterranean climate, a climate characterized by mild, wet winters
and long, hot, dry summers. That climate selects for plant species able to
survive the long dry season and to resume growth rapidly upon the return
of the rains. Many Fertile Crescent plants, especially species of cereals and
pulses, have adapted in a way that renders them useful to humans: they are
annuals, meaning that the plant itself dries up and dies in the dry season.
Within their mere one year of life, annual plants inevitably remain small
herbs. Many of them instead put much of their energy into producing big
seeds, which remain dormant during the dry season and are then ready to
sprout when the rains come. Annual plants therefore waste little energy on
making inedible wood or fibrous stems, like the body of trees and bushes.
But many of the big seeds, notably those of the annual cereals and pulses,
are edible by humans. They constitute 6 of the modern world's 12 major
crops. In contrast, if you live near a forest and look out your window, the
plant species that you see will tend to be trees and shrubs, most of whose
body you cannot eat and which put much less of their energy into edible
seeds. Of course, some forest trees in areas of wet climate do produce big
edible seeds, but these seeds are not adapted to surviving a long dry season
and hence to long storage by humans.
A second advantage of the Fertile Crescent flora is that the wild ancestors
of many Fertile Crescent crops were already abundant and highly productive,
occurring in large stands whose value must have been obvious to
hunter-gatherers. Experimental studies in which botanists have collected
seeds from such natural stands of wild cereals, much as hunter-gatherers
must have been doing over 10,000 years ago, show that annual harvests
of up to nearly a ton of seeds per hectare can be obtained, yielding 50
kilocalories of food energy for only one kilocalorie of work expended. By
collecting huge quantities of wild cereals in a short time when the seeds
were ripe, and storing them for use as food through the rest of the year,
some hunting-gathering peoples of the Fertile Crescent had already settled
down in permanent villages even before they began to cultivate plants.
Since Fertile Crescent cereals were so productive in the wild, few addi-