White tigers are neither a species nor a subspecies, but appear as a result of a recessive trait that rarely occurs in the wild. In the 1950s many zoos deliberately and indiscriminately bred white tigers, but more recently, concerns about the desirability of preserving a trait that presumably hinders tigers' to survive in the wild, and recognition that inbreeding could lead to genetic defects, have caused most zoos to such practices. However, some zoo managers argue that the popularity of white tigers provides income important to the survival of zoo sponsored scientific and conservation programs. They also point out that most of the white tigers captured in the wild were adults, proving that their coloration does not hinder their survival ability.
Opponents of white-tiger breeding programs argue that white tigers are merely Indian tigers—a subspecies well represented in both zoos and the wild—and that zoos should focus their tiger management efforts on preserving subspecies whose existence is threatened, thus preventing the Chinese and Indochinese tiger subspecies from joining the Javan, Balinese, and Caspian subspecies in extinction. Alternatively, zoos could mingle the subspecies and manage all tigers in captivity as one species. Although subspecies differences would be lost, this strategy would be advantageous because fewer animals would be necessary to maintain the genetic diversity of tigers in captivity, making scarce zoo resources available for housing other endangered felines.
The passage suggests that, compared with other tiger subspecies, the Indian tiger is
less threatened by extinction
less readily bred in captivity less
likely to survive in the wild
more likely to be bred indiscriminately
more popular with zoo visitors
此讲解的内容由AI生成,还未经人工审阅,仅供参考。
正确答案是 A。文章暗示了比其他老虎亚种而言,印度老虎不太受到灭绝威胁。文章称,一些动物园管理人员认为,白色老虎的普及为动物园提供了重要的收入,以支持动物园赞助的科学和保护计划,但是,反对繁育白色老虎的计划的人认为,白色老虎只是印度老虎-一个在野外和动物园中都很常见的亚种,因此,动物园应该把老虎管理工作重点放在保护受威胁亚种上,以防止中国和印度支那老虎亚种加入爪哇、巴厘岛和里海亚种的濒危行列。由此可见,与其他老虎亚种相比,印度老虎不太受到灭绝威胁,因此,本题的正确答案是 A。
破折号内容常考+后面取非
登录 或 注册 后可以参加讨论