英语听力文摘 English Digest 675 雄性的未来

搜索关注在线英语听力室公众号：tingroom，领取免费英语资料大礼包。

　　Have you ever heard predictions that one day women will be able to have babies without men? It turns out that some species of the Whiptail lizard¹ have figured out how to do this and completely eliminated the male sex.

　　Females Cloning Themselves

　　The females have the ability to lay eggs that hatch and grow into healthy lizards² without needing to be fertilized³ by a male. The offspring are exact and complete genetic⁴ duplicates of the mothers.

　　Essentially⁵ the females are clonnig themselves.

　　Role Playing

　　If that weren’t enough, the female lizards take turns role-playing. They perform a mating ritual in which one lizard acts like the male, and the second lizard acts like the female. The ritual causes the lizard acting⁶ as the female to ovulate and lay her eggs. Then, a few weeks later, the two lizards switch roles and repeat this process so that the second female will be able to ovulate and lay her eggs.

　　Genetic Variation

　　It raises a lot of interesting questions. For example, it’s not clear how well an all female species can evolve and adapt to environmental changes. A species’ survival depends in part on variation among its members. If all the members of a species are identical, chances are greater that something like a change in the climate or a disease will wipe them all out.

分享到：