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. [...] 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...