Gaylord Simpson, Biology and Man. To many people the answer must seem obvious. To ask the question at all is naive. By reason of these man becomes a unique creator of culture. Yet for all this, the feeling persists that such specialized features single man out as unique not so much because he is the only animal which has them, but because he has them in forms so much more highly developed than other creatures do.
Some animals seem to be self-conscious at times.
A few animals can stand erect, and some apes can even run erect for short distances. And a few species are able to oppose their thumbs in gsasping things. So it could be said that man is, after all, only quantitatively different, different in degree but not essentially different in any classificatory sense. Perhaps the most satisfactory way of describing man's status is to say that he is unique in having a unique combination of abilities, rather than in the possession of any single attribute. In this way, quantitative differences, when they grow very large, become qualitative differences.