GUNS, GERMS AND STEEL - Cloverport Independent Schools

I 6 6 • GUNS, GERMS, AND STEEL
of the last Ice Age. As summarized in Table 9.3, the era of big mammal
domestication began with the sheep, goat, and pig and ended with camels.
Since 2500 B.C. there have been no significant additions.
It's true, of course, that some small mammals were first domesticated
long after 2500 B.C. For example, rabbits were not domesticated for food
until the Middle Ages, mice and rats for laboratory research not until the
20th century, and hamsters for pets not until the 1930s. The continuing
development of domesticated small mammals isn't surprising, because
there are literally thousands of wild species as candidates, and because
they were of too little value to traditional societies to warrant the effort of
raising them. But big mammal domestication virtually ended 4,500 years
ago. By then, all of the world's 148 candidate big species must have been
tested innumerable times, with the result that only a few passed the test
and no other suitable ones remained.
STILL A FOURTH line of evidence that some mammal species are much
more suitable than others is provided by the repeated independent domestications
of the same species. Genetic evidence based on the portions of
our genetic material known as mitochondrial DNA recently confirmed, as
had long been suspected, that humped cattle of India and humpless European
cattle were derived from two separate populations of wild ancestral
cattle that had diverged hundreds of thousands of years ago. That is,
Indian peoples domesticated the local Indian subspecies of wild aurochs,
Southwest Asians independently domesticated their own Southwest Asian
subspecies of aurochs, and North Africans may have independently
domesticated the North African aurochs.
Similarly, wolves were independently domesticated to become dogs in
the Americas and probably in several different parts of Eurasia, including
China and Southwest Asia. Modern pigs are derived from independent
sequences of domestication in China, western Eurasia, and possibly other
areas as well. These examples reemphasize that the same few suitable wild
species attracted the attention of many different human societies.
THE FAILURES OF modern efforts provide a final type of evidence that
past failures to domesticate the large residue of wild candidate species
arose from shortcomings of those species, rather than from shortcomings