The most important aspect of human evolution was facilitated
not by Darwinian-style natural selection but by a crucial technological device
invented by early Stone Age women, shows research by a leading British
prehistorian.
Timothy Taylor of Bradford University claims that increased
brain size was made possible by the invention of the baby sling, a development
which enabled slower growing, physically and mentally immature offspring to
survive and flourish.
"In effect, kangaroo-style, early female human
ancestors became marsupial, carrying their immature youngsters outside their
wombs," said Dr Taylor, who has published his research in a book called
The Artificial Ape.
"The invention of the baby sling, which allowed more
babies to successfully mature outside the female body, instantly removed the
barrier to increased head and brain size."
Before the invention of the baby sling, dated by Dr Taylor
to at least 2.2 million years ago, when human ancestor head size suddenly began
to increase, physically mature infants were more likely to survive, because
caring for slower-developing immature ones was difficult, uneconomic and often
dangerous.
Mothers holding their infants were more vulnerable to attack from
predators or other humans than those using baby slings. They were also less
able to perform other more economically productive tasks.
Most importantly, the invention of the baby sling
artificially lengthened human gestation, said Dr Taylor. Formerly, gestation
ended at birth with the most physically mature babies surviving as they needed
to be carried by their mothers for less time. But their head and brain size was
strictly limited by the width of their mother's pelvis.
"Courtesy of the baby sling, our ancestors got
smarter," he added.
Article by David Keys, Archeological Correspondant of “The
Indipendent”
Monday 06 September 2010
Source:http://www.independent.co.uk
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