kadabba to be a "chronospecies" of Ar. ramidus, bearing the same relationship to it that Au.

大多数科学家认为地猿卡达巴只不过是地猿始祖种的一个“年代种（chronospecies）”，二者之间存在的某种亲缘关系，就如同南猿湖畔种与南猿阿法种之间的相互联系：同一基本方案的一个较早期版本。

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Foot bones from the species Ardipithecus ramidus and Ardipithecus kadabba have features diagnostic of bipedalism.

BBC: NEWS | Science/Nature | Scientists unearth early skeleton