现代人的脑重约为其整个体重的五十分之一。可以说是每克脑负责 50克身体。与之相比较,黑猩猩脑重约为体重的一百五十分之一,大猩猩则约为其体重的五百分之一。诚然,有些较小的灵长类脑重与体重的比率比人类还高些(蜂鸟也这样)。猴子的脑可为它体重的十八分之一。然而, Modern human brains weigh about one-fifth of their entire body weight. It can be said that it is responsible for 50 grams of body per gram of brain. In contrast, chimpanzees weigh approximately one-hundred and fifty-oneths of their body weight, while gorillas weigh approximately five-hundredths of their body weight. It is true that some of the smaller primates have higher brain-to-weight ratios than humans (as do hummingbirds). The monkey’s brain can be one-eighteenth of its weight. however,