The beginnings of trade
Stone tools have been found great distances from the sources of the stone
from which they are made. Amber, oyster shells, copper, turquoise,
malachite, and dyes used in cosmetics have also been found at pre-historic
sites substantially distant from their sources. Although the foraging
bands of this period were largely self-sufficient, individual groups may
have had easy access to some uncommon item that might have been desired by
others. The favored group could gather such an item, for example, chert
stone blanks, seashore shells, or bear claws, and trade them to other
groups for items that the first group desired, but to which it had no easy
access. The copper in ornaments found in the native settlements of
Florida, for example, originated in Michigan and Minnesota.
The scattered foraging groups within a large region may have come together
regularly, perhaps during the bountiful summer or fall seasons, to
celebrate, select mates, and trade. Such gatherings would also have been a
likely time for new technologies to be shared.
Trade and towns
Trade increased in importance after the first towns appeared. Within the
town the different task specialists had to trade the results of their work
for the things they needed. The increasing importance of task
specialization required a more sophisticated arrangement of bartering so
the residents could trade the results of their labor for the necessities
and luxuries they desired.
Trade also flourished between towns. When two different towns each had
access to something the other did not have but wanted, there was an
obvious basis for trading. Even when both could obtain or produce the same
items, there might have been a benefit from trading. Each might have
specialized in the production of a particular good or food item, traded
with each other, and ended up with more of both items than they would if
they had tried to meet their needs separately. This comparative advantage
from trading might arise because one town had better farmland and the
other better grazing land. Or one might have had easier access to metallic
ores while the other was surrounded by rich bottom land.
Within towns the specialization of tasks and the prospect of profit
increased the rate of technological improvement. The expert had an
incentive to find ways to be more productive. Greater productivity either
made him materially better off or allowed for greater leisure time.
Trade between towns also helped increase the rate of technological change
by expanding markets and bringing different cultures into contact. Distant
markets further encouraged specialists to find better ways to make things.
Trading between towns and regions helped spread new technologies more
quickly and more widely, reducing the chance that an important innovation
might be temporarily lost.
The demands of business and trade eventually led to the development of
money that served as a medium of exchange, a storehouse of value, and a
standard of value. Silver rings or bars are thought to have been used as
money in ancient Iraq before 2000 BC. The first coins were made of
electrum, a naturally occurring and easily malleable alloy of gold and