Today, we see how a genetic mutation gave birth to
our civilization. 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.
To fulfill our destiny as a
species of builders and makers, we first had to leave
hunting and gathering to take up farming. The
scientist and historian Jacob Bronowski tells a
remarkable tale of plant genetics that suggests this
change came down to a key flash of human ingenuity.
Archaeological evidence makes it clear that two
stages of genetic change set the stage. Before 8000
BC, the ancestor of wheat more closely resembled a
wild grass than the heavy grain-bearing plant we eat
today. Then a mutation occurred in which this plant
was crossed with another grass. The result was a
fertile hybrid called emmer with edible
seeds that blew in the wind and sowed themselves.
The hunting-gathering tribes took to harvesting and
eating these seeds. But they didn't have to worry
about planting emmer, because it sowed itself.
Then a remarkable thing happened. A second genetic
mutation occurred sometime between 8000 and 6000 B.C.
This mutation yielded something very close to our
modern wheat, with its much plumper grain. It may
have happened many times before that, but if it did
we'd have no way of knowing, because wheat doesn't
blow in the wind, and it can't sow itself. A mutation
-- even a fertile one -- couldn't survive on its own.
Modern wheat survives only in a symbiotic
relationship with humans. Without someone to harvest
it and plant it, it dies away. But somehow some very
clever person spotted one of these mutations of emmer
and recognized the potential of collecting and
manually replanting the seeds. A hunter-gatherer
conceived of farming.
This pivotal event in human history happened rather
close to the beginning of biblical chronology -- the
chronology of humankind once it took up farming. This
was the prototypical act of a kind of technological
creativity that's gone on ever since. Someone
happened across an oddity -- in this case, a stalk of
fat grain that couldn't ride the wind -- and saw
possibility within it. That person saw how to cast
what was evident into a new arrangement and to gain a
result that was not evident at all.
I'm John Lienhard, at the University of Houston,
where we're interested in the way inventive minds
work.
(Theme music)
Bronowski, J., The Harvest of the Seasons. The
Ascent of Man. Boston: Little, Brown and
Company, 1973, Chapter 2.
I deal with the invention of agriculture in
accordance with more up-to-date source material in
Episodes 540 and 571.
top: Modern white Gaines wheat.
middle: Emmer
bottom: A wild wheat-like grass, triticum
monococcum.
The Engines of Our Ingenuity is
Copyright © 1988-1997 by John H.
Lienhard.
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