题型：阅读理解 题类：常考题 难易度：普通
安徽省师范大学附属中学2019届高三上学期英语期中考试试卷
Since the sex of a sea turtle(海龟)is determined by the heat of sand hatching the eggs, scientists had suspected they might see slightly more females. Climate change, after all, has driven sea temperatures higher, which, in these creatures, favors female children. They found female sea turtles from Raine Island, the Pacific Ocean's largest and most important green sea turtle living area, now outnumber males by at least 116 to 1. "This is extreme," says turtle scientist Camryn Allen.
Biologist Michael Jensen wanted to know if climate change had already changed turtles' sexes. By using genetic(基因的) tests, he'd figured out that he could follow turtles of all ages. Still, his research data would lack an important detail: sex. Only after a turtle matures is it possible to tell its sex from the outside -- mature males have slightly longer tails. By then turtles can be decades old, so scientists often use Iaparoscopy(腹腔镜检查)，sending a thin tube into each animal, but that's not so practical if you're hoping to examine hundreds of creatures. Fortunately, at a turtle conference, he met Allen, and all she needed was a little blood.
They compared their results with temperature data for nesting beaches. What worries them is that Raine Island has been producing almost female turtles for at least 20 years. This is no small thing. More than 200,000 turtles come to nest there. During high season, 18,000 turtles may settle in at once. "But what happens in 20 years when there are no more males coming up as adults? Are there enough to maintain the population?" says Allen. They also found cooler beaches in the south are still producing males, but that in the north, it's almost entirely females hatching. These findings clearly point to the fact that climate change is changing many aspects of wildlife biology.
But how widespread is this phenomenon -- and what is the consequence?
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