Because this effect has been observed in three primate species, most recently in a study of chimpanzees, it suggests this effect has evolutionary roots.

因为人们已在三个灵长类生物间发现了这种效应。最近的是在一个关于黑猩猩的研究中，它提出这种效应有进化论的根基。

youdao

It has three roots.

这种情绪有三个根源。

youdao

They then ate only bark and roots for another three years and began drinking a poisonous tea made from the SAP of the Urushi tree, normally used to lacquer bowls.

接下来的三年他们将只食用树皮和树根，并且饮用漆碗所盛，漆树树液所制的毒茶。

youdao

Roots of Peace says a landmine costs anywhere from three to thirty dollars to produce and place in the ground.

VOA: special.2010.05.03

Many growers like to start with two to three year old roots instead.

VOA: special.2009.04.07

And I set down roots three blocks from where I grew up.

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If the roots extend past three feet, chances are good that they can support the tree.

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The Hindu Rights Action Force (HINDRAF), a political group that Malaysia has banned, circulated a fiery report on the plight of Malaysia's Indians, many of whom trace their roots to indentured labourers shipped to the peninsula three or four generations ago.

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