A recent research by a leading British prehistorian maintains that the most important aspect of human evolution was facilitated by a crucial technological device invented by early Stone Age women. Archaeologist and anthropologist 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. "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.
     "The implications of this development were enormous. It meant that babies could continue to develop outside the womb after birth and that their brains could continue to grow. They were not constrained by the size of their mothers' pelvises and could grow bigger and bigger for years. It gave us scope for intellectual expansion. Most importantly, the invention of the baby sling artificially lengthened human gestation," said Dr Taylor.  
     We did not invent technology, Dr Taylor argues. Technology invented us. "Courtesy of the baby sling, our ancestors got smarter," he concluded.

Edited from The Guardian (5 September 2010), The Independent (6 September 2010)