人類新生兒體重高有助於社會穩定

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。

最新研究顯示，人類嬰兒出生時比其他任何靈長類物種的新生兒都要重，人類的原始祖先很有可能亦是如此。一位美國研究人員稱，這種(出生狀況的差異)有可能影響現代人類社會的發展，甚至對決定現代人類社會模式起到了推動作用。

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."

一個人類新生兒平均是其母親體重的6%， 而一個新生猿則縮減至(其母親體重的)3%。波士頓大學的人類學家傑里米 波塞瓦對這種差異並不滿意：“從各種角度來看，人類都很奇怪。我們用兩條腿直立行走，我們的新生寶寶非常無助，也大得不尋常。他們通常有個大大的腦袋，同其他靈長類動物比起來，他們的身體也大得不一般。”

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。

爲了驗證人類百萬年前的祖先，比如南方古猿，(其新生兒)是否也(比其他靈長類動物)更重，波塞瓦對南方古猿顱骨進行了分析。“得知這些頭顱的數據後，(我們發現這些顱骨也符合)研究人員所謂的‘12%定律，’”他說道。“12%定律”是指，(人類)大腦重量佔全身總重的12%。他補充說這些古猿的腦重與總重比更趨近於10%，和人類這一比例接近。

DeSilva believes that rearing large babies has had a significant influence on human culture, even helping to stabilize communities。

波塞瓦認爲(人類)罕見的大號嬰兒(現象)對人類文化產生了重要影響，甚至有助於社會穩定。