托福听力练习对照文本第五十篇

　　Human populations near the equator have evolved dark skin over many generations because of exposure to the fierce rays of the Sun.

　　赤道附近的人类种群由于曝露在强烈的太阳光线中，在经过很多代之后已经进化出了深色的皮肤。

　　A similar phenomenon has also occurred in other parts of the animal kingdom.

　　一个类似的现象也发生在动物王国的其他其他部分。

　　The African grass mouse is a good example.

　　非洲草鼠是个很好的例子。

　　Most mice are nocturnal, but the African grass mouse is active during daylight hours.

　　大多数老鼠是夜间活动的，但是非洲草鼠在白天的时候活跃。

　　This means that it spends its days searching for food in the semidry bush and scrub habitats of eastern and southern Africa.

　　这意味着它花费它的白天(时间)寻找食物，在东部和南部非洲的半干的灌木丛栖息地中。

　　Its fur is striped, like a chipmunk's, which helps it blend in with its environment.

　　它的皮毛是有条纹的，像金花鼠的(皮毛)，这帮助它融入了它(周围)的环境。

　　Because it spends a lot of time in the intense tropical sun, the grass mouse has also evolved two separate safeguards against the Sun's ultraviolet radiation.

　　由于它在强烈的热带阳光中度过了很多时间，草鼠还逐步形成了两项单独的保护措施抵御太阳的紫外线辐射。

　　First, like the populations of humans in this region of the world, the skin of the grass mouse contains lots of melanin, or dark pigment.

　　第一项，像在世界的这个区域的人类种群一样，草鼠的皮肤包含了很多黑色素，或者说黑的色素。

　　Second, and quite unusual, this mouse has a layer of melanin-pigmented tissue between its skull and skin.

　　第二项，而且相当不同寻常(的是)，这种老鼠在它的头盖骨和皮肤之间有一层黑色素着色的组织。

　　This unique "cap" provides an extra measure of protection for the grass mouse and three other types of African mouse-like rodents that are active during the day.

　　这个独特的“帽子”为草鼠和其他三种非洲的类鼠的啮齿类动物提供了一项额外的保护措施。

　　The only other species scientists have identified with the same sort of skull adaptation is the white tent-making bat of the Central American tropics.

　　科学家已经鉴定的有同样的头骨的适应(形式的)唯一的另外的物种是中美洲热带地区的白尾皮蝠

　　Although these bats sleep during the day, they do so curled up with their heads exposed to the sun.

　　虽然这些蝙蝠在白天的时候睡觉，它们这样做(晒太阳)把头部暴露在阳光下地蜷缩着