Today, let's watch an archaeologist do detective work. 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.
Abu Hureyra is an archaeological site in Northern Syria.
Theya Molleson has been studying skeletons of the people who
lived there between 8000 and 5000 BC. She asks an old question:
"How do we change technologically?" The skeletons answer her.
Let's begin with big toes on the women's right feet: They're
bent upward. How odd! Did these late stone age people play some
strange sport? Did women have to kick a stone football about?
Then someone pointed to Egyptian pictures of kneeling supplicants.
The big toe bends against the ground. Sure enough,
Molleson's women had enlarged tibias where the knee would meet
the ground. But why should women spend long periods kneeling?
And why only the right toe? Back to the skeletons: Women's lower
backs and elbows show signs of having been worked very hard.
Finally Molleson has the picture. Imagine you're a woman
grinding grain on a long flat quern or grinding stone. You kneel
with your left foot crossed over the right to give you a stable
three-point suspension. You roll a cylindrical pestle back and
forth over grain on the stone. Backbreaking work!
Of course, that means these people had agriculture 9500
years ago. It also means they differentiated tasks among men and
women. Men hunted and grew grain; women ground the grain.
That explains another skeletal defect. Early skulls of both
sexes show badly fractured teeth. The problem with "stone ground"
grain is that stone flakes into the grain. Stone fragments and
partly ground kernels do terrible damage to teeth over the years.
Later, Molleson finds less tooth damage. She finds, instead,
that just a few women have deep grooves in their front teeth --
the same grooves you find on the teeth of modern Paiutes who use
their mouth as a third hand to hold canes when they weave baskets.
Around 6500 BC, Abu Hureyra women invented weaving, but
weaving was a job that only a few craftswomen did.
And weaving led to the invention of sieve making. So the
problem of tooth damage was partly solved by sifting out stones
and hard kernels. Later, the Abu Hureyrans acquired another new
technology that finished solving the problem of tooth destruction.
By 5300 BC they'd learned to make clay pots in which to
soak grain and cook cereal. They'd begun eating porridge.
Those old bones say much about how technology went into high
gear in the late paleolithic period. Soon the kin of these
people would add the wheel, cloth, metal-working -- and writing.
Molleson's skeletons were first in the same line of technologists
who are now making space ships -- and genetically engineered food.
I'm John Lienhard, at the University of Houston, where we're
interested in the way inventive minds work.