There are two other kinds of research that have thrown some light on the origins of the Native American population; they involve the study of teeth and of languages.

还有另外两种研究对印第安人的起源提供了一些线索；它们包括对牙齿和语言的研究。

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In some case, non-native species of oysters are introduced after a population decline, and they bring with them diseases that further kill off the native oysters.

在一些例子中，非本土种类的牡蛎会在本土数量下降后引入，它们随身带来的疾病会进一步杀死光本土牡蛎。

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He denounced the "semi-gangs, some of them ethnic" that controlled Russia's markets, and called for regulation to protect "the native Russian population".

他对那些控制俄罗斯市场，“黑帮性质的(其中有些是由少数族裔组成)”的组织予以了谴责，并呼吁采取管制措施保护“土生土长的俄罗斯人”，新法规遂得以出台。

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Not only does this increase the political popularity of the program and provide a way to transfer some of the gains of immigration to the native born population, but it also serves as an enforcement mechanism.

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