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首页> 外文期刊>Current Science: A Fortnightly Journal of Research >African elephants: surviving by the skin of their teeth
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African elephants: surviving by the skin of their teeth

机译：非洲大象：靠牙齿的皮肤生存

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摘要

The African elephant’s misfortune has been its teeth, in particular the welldeveloped pair of upper incisors known as tusks for which it is being killed in large numbers. The visible ivory part of the tusks is made up of dentine with an outer layer of enamel, and when viewed in cross-section it reveals criss-cross lines that form a series of diamond shapes. This is what gives the elephant ivory its distinctive lustre, and makes it so valuable economically. Ivory has been an item of international trade since ancient times, exploited commercially by the Romans, Arab traders and Europeans. Man’s avarice and greed for ivory have been responsible for the senseless slaughter of hundreds of thousands of elephants in Africa where both sexes carry tusks. Indiscriminate poaching for ivory coupled with the expansion of human populations and desertification have been identified as the principal causes for the decline in range and number of the African elephant.
机译：这头非洲象的不幸之处在于它的牙齿，尤其是一对发达的上齿门牙（称为象牙），因此被大量杀害。牙的可见象牙部分是由牙本质和搪瓷外层组成，从横截面看，它揭示出纵横交错的线条，形成了一系列菱形。这就是赋予大象象牙独特的光泽，并使其在经济上如此有价值的原因。自古以来，象牙一直是国际贸易的一个项目，被罗马人，阿拉伯商人和欧洲人进行商业开发。人类的贪婪和对象牙的贪婪是造成非洲成千上万的大象被无意识地屠杀的原因，非洲的两性都带有象牙。象牙的滥砍滥伐，加上人口的增加和荒漠化，已被确定为造成非洲象的范围和数量下降的主要原因。

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