Question

【题目】 The Bialowieza Forest, which grows along the border of Poland and Belarus(白罗斯), is all that remains of the primeval(原始的) forest which once covered Europe. A World Heritage site since 1979, the forest covers an area of 550 square miles. Wolves prowl(潜行) beneath the ancient trees. Running closer to the ground are least weasels(伶鼬). They come in two types. One wears a brown coat all year. The other sheds its brown coat each autumn and turns bright white. It is believed to be an adaptation to help it blend in with snow.

However, there was no snow cover when biologist Karol Zub, at the Polish Academy of Sciences, observed an entirely white weasel hunting rodents(啮齿动物). 【1】 “At this very moment, I thought to myself. Wowl if this animal is so well visible, it must be a perfect target for predators,” Zub said.

His instincts were right 【2】 Zub and his colleagues analyzed weather data in the Bialowieza Forest going back to 1967. The average period with permanent snow cover decreased from about 80 days per year to 40 days. Historically, the snow cover disappears around Mar. 15. But in recent years, it disappeared by Feb. 21, more than three weeks earlier in the season. And there are fewer white weasels are about four to five times lower than then years ago.

As the number of days without permanent snow cover increased, the proportion of white weasels dropped dramatically. This crop is a case of what wildlife biologists call “camouflage(伪装) mismatch.” 【3】 Camouflage mismatch may cause the local extinction of white weasels, or at least a severe reduction in population.

【4】 Those who blend in live longer. Individuals who clash with their environment get eaten. There are 21 species known to change the color of their coats in winter. Zub predicts the other coat-changers are faring(遭遇) as badly as the humble weasel.

Life on Earth is reacting to climate change. Bears appear to be hibernating for fewer days. Tropical fish are swimming away from the equator in search of cooler waters. Some animals have moved up into the mountains to escape increased temperatures. But camouflage mismatch might be one of the worst effects. After all, it’s hard not to notice a flash of white fur in a dark forest.

Answer 1

【答案】

【1】C

【2】A

【3】E

【4】D

【解析】

这是一篇说明文。文章主要说明了随着气候的变化，以白鼬为例的动物们的伪装与自然环境形成了“伪装错配”而导致了他们白色的毛皮在没有雪的时候就变成了一种容易被捕食动物发现的致命弱点。伪装的不匹配可能会导致白鼬的局部灭绝，或者至少是数量的严重减少。故说明了自然选择的机制对于人和动物来说是完全相同的。

【1】结合下文“At this very moment, I thought to myself. Wowl if this animal is so well visible, it must be a perfect target for predators,” Zub said.（就在这时，我想。如果这种动物如此显眼，它一定是食肉动物的完美目标。”祖布说。）可推知波兰科学院的生物学家Karol Zub观察到一只完全白色的鼬鼠在捕食啮齿动物时，那里并没有积雪覆盖。它的皮毛与青苔形成鲜明的对比。因此很显眼。故C选项承上启下符合语境。故选C。

【2】结合下文The average period with permanent snow cover decreased from about 80 days per year to 40 days.（永久积雪的平均周期从每年约80天减少到40天。）可知雪不再像以前那样长时间覆盖森林了，他的直觉是正确的。故A选项符合语境。故选A。

【3】根据下文Camouflage mismatch may cause the local extinction of white weasels, or at least a severe reduction in population.（伪装的不匹配可能会导致白鼬的局部灭绝，或者至少是数量的严重减少。）可知积雪天数的减少，使得白鼬白色的毛皮在没有雪的时候变成了一种容易被捕食者发现的弱点，这造成了伪装的不匹配。故E选项符合上下文语境。故选E。

【4】根据下文Those who blend in live longer. Individuals who clash with their environment get eaten.（融入群体的人寿命更长。与环境冲突的个体会被吃掉。）可推知自然选择的机制对于动物和人类一样是完全相同的。故选D。