Today, a Paleolithic story of the tortoise and the
hare. The University of Houston's College of
Engineering presents this series about the machines
that make our civilization run, and the people
whose ingenuity created them.
A group of anthropologists
from Arizona and Israel has been digging in Italy
and Israel. They've been studying a surprising
Paleolithic population explosion, and they've
linked it to a key discovery: Some 40,000 years
ago, humans began eating differently.
For hundreds of thousands of years, much of the
human diet was made up of mollusks and tortoises.
And what do such creatures have in common? They're
slow-moving and easy to catch. When you get hungry,
you go out and pick up a turtle.
The problem is, those species are easy to kill off.
Killing even seven percent of a tortoise population
will upset its balance and threaten its survival.
That ancient diet could work only while the
population of human predators was very small.
So diet becomes an index to population. Human
populations were, it seems, all small before the
recent stone ages. Other evidence has shown that
the population of Africa was once as small as 7000
people. It probably consisted of wide-ranging bands
of 250 to 500 people -- the minimum needed to
satisfy universal taboos against incest. The group
that finally moved out of Africa to populate the
rest of the world was probably about that size.
When the human population began increasing, its
diet had to change. Vulnerable, slow-moving species
could no longer support humans. Humans had to start
eating the fast-moving animals -- birds and hares.
It was time to invent or die off. Anthropologists
start finding barbed spear tips, snares, nets, and
throwing devices.
All this brings us back to the definition of the
word technology. That word combines
the Greek word tecnh
with ology. Tecnh
means art and skill in making things. Ology means
the knowledge of, or the science of, or maybe the
lore of. Technology is the knowledge of making
things. It is sharing that knowledge. Sharing the
knowledge of technique was the essential step that
made us into a species defined by our constant
remaking of the material world.
So anthropologists look at the cooled ashes of old
fires and find, mixed in among them, bones of
creatures that could once outrun us, out-fly us,
and (perhaps) even out-think us. But no more. The
old term hunter-gatherer divides in two.
Gatherers no more, we became hunters who joined
about the fire to tell one another what we had
thought up today. And to do that, we needed another
skill, the skill of speech. We're pretty sure that
humans learned speech about the same time the bones
of fast-moving prey appeared in the ashes of their
campfires.
Embedded in all this is a reminder that creativity
is communal; invention is sharing and serving the
common good. To be anything but thinly scattered
gatherers, we first define ourselves as sharers of
technique. Then we go all the way with that
definition. The odd corollary is that nothing
halfway is possible.
I'm John Lienhard, at the University of Houston,
where we're interested in the way inventive minds
work.
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