29 JUN 2011 by ideonexus
Effect of Human Brain Size on Labor and Bipedalism
The real obstetrical dilemma came long after Lucy and her colleagues became extinct, when there was a sudden upsurge in brain expansion. About 1.5 million years ago, die adult hominid brain went from the Australopithecine size of 400 cubic centimeters to 750 cubic centimeters in a species called Homo habilis, the first member of our genus. In other words, the brain just about doubled in size. A mere million years later. the hominid brain doubled once again until it reached its present average...
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Painful labor is a compromise between our large brain size and the ability of a woman to give birth mechanically.
30 MAR 2011 by ideonexus
Breast Feeding Fuels Big Brains
The study looked at the average pregnancy term, breast-feeding length and brain size of 128 species of mammals. They saw that between different species brain size at birth was determined by the length of pregnancy, while the brain growth after birth was determined by breast-feeding duration.
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The extreme length of pregnancy and breast-feeding in humans (nine months and three years, respectively) is required for the growth and development of our large brains, which can reach 79 cubic in...Women should breast-feed for at least six months and up to two years to encourage the growth of the infant's brain as much as possible.
