Schwartz J H
Nature. 1984;308(5959):501-5. doi: 10.1038/308501a0.
Man shares uniquely few morphological features with either the chimpanzee or the gorilla, whereas there are many features that suggest affinities between man and the orang-utan, to whom the fossil Sivapithecus appears to be closely related. If these are unique features, inclusion of Sivapithecus, man and the orang-utan in a single clade, distinct from that containing the African apes, is justified but contrary to current opinion.
人类与黑猩猩或大猩猩共有的独特形态特征极少，而有许多特征表明人类与猩猩之间存在亲缘关系，化石西瓦古猿似乎与猩猩密切相关。如果这些是独特特征，那么将西瓦古猿、人类和猩猩归入一个与包含非洲猿类的分支不同的单一分支是合理的，但这与当前观点相悖。
