部分原因事因为哺乳动物的牙齿保存的十分完好。

That's partly because mammals' teeth preserve really well.

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通过对阿迪牙齿的分析表明阿迪平常所吃的食物是无花果以及其它水果、树叶和小型哺乳动物。

Analysis of Ardi's teeth points to a diet of figs and other fruit, leaves and small mammals.

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裂齿，食肉齿适合于撕裂肉的牙齿，尤指食肉哺乳动物最后上前臼齿之一或第一个下臼齿。

A tooth adapted for tearing apart flesh especially one of the last upper premolar or first lower molar teeth in carnivorous mammals.

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