Humanbabiesweighmoreatbirththanthenewbornsofanyotherprimatespecies,andsoitisprobablywiththeearliesthumanancestors.Thismayhaveinfluencedthedevelopmentandevenhelpeddefinetheshapeofmodernhumansocieties,a...Human babies weigh more at birth than the newborns of any other primate species, and so it is probably with the earliest human ancestors. This may have influenced the development and even helped define the shape of modern human societies, a US researcher said.
A human baby weighs an average of six percent of what its mother weighs while a baby ape shrinks to only three percent. Jeremy DeSilva, an anthropologist at Boston University, was not satisfied about this difference: "Humans are strange, in all sorts of ways. We walk upright on two legs and our newborns are helpless. Our babies are unusually large. They have unusually large heads; they have unusually large bodies compared to other primates."
一个人类新生儿平均是其母亲体重的6%， 而一个新生猿则缩减至(其母亲体重的)3%。波士顿大学的人类学家杰里米 波塞瓦对这种差异并不满意：“从各种角度来看，人类都很奇怪。我们用两条腿直立行走，我们的新生宝宝非常无助，也大得不寻常。他们通常有个大大的脑袋，同其他灵长类动物比起来，他们的身体也大得不一般。”
To find out if species that were around millions of years before humans, such as Australopithecus, also weighed more, DeSilva analyzed Australopithecus skulls. "So once you have the size of the head, there is what researchers have called 'the 12 percent rule,'" he said. The 12 percent rule says that the brain represents 12 percent of the total body weight. He added that the apes tend to be more like 10 percent, similar to the humans.
DeSilva believes that rearing large babies has had a significant influence on human culture, even helping to stabilize communities.