书城外语课外英语-动物亮丽风景线(双语版)
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第24章 河马

河马原来遍布非洲所有深水的河流与溪流中,现在范围已缩小,主要居住在非洲热带的河流间。它们喜欢栖息在河流附近沼泽地和有芦苇的地方。生活中的觅食、交配、产仔、哺乳也均在水中进行。

河马的特点是吻宽嘴大,四肢短粗、躯体像个粗圆桶。鼻孔在吻端上面,与上方的眼睛和耳朵呈一条直线。这样它全体潜伏水中只须将头顶露出水面就能嗅、视、听兼呼吸了。

河马皮肤排出的液体含红色色素,经皮肤反射显得像是红色的,引起了河马出“血汗”的说法。

河马极善游泳,在受惊时,一般避入水中。每天大部分时间在水中,潜伏水下时一般每3至5分钟把头露出水面呼吸一次,但可潜伏约半小时不出水面来换气。它们的皮肤长时间离水会干裂。

河马成对或结成小群活动,老年雄性常单独活动。夜行性:它们几乎整个白天都在河水中或是河流附近睡觉或休息,晚上出来吃食,有时会顺水游出30多公里觅食。主要以水生植物为食;偶食陆地作物,以草为主,有时到田地去吃庄稼,造成很大损害。河马无定居:不在一个地方长期停留,每隔数日便迁到新地方去。

河马繁殖期不固定,全年均繁殖,每产一仔,孕期227-240天,仔兽出生时体重27-45公斤。在人为饲养下约3岁性成熟,在野外五六岁成熟。寿命40-50年。

河马的皮下脂肪约5厘米厚。人们常猎杀它取其脂肪、肉和厚皮。脂肪可得90公斤。当地人非常珍视它的肉。牙齿质量也很好。

If a pig weighed as much as a pickup truck it might look something like a river hippopotamus.A hippopotamus,or hippo,is an animal that lives in Africa.Like a pig,it has a tubby body,big head,and short,thick neck.In fact,the hippopotamus is a distant relative of the pig.

The hippopotamus lives in Africa.There are two kinds of hippopotamuses—the river hippopotamus and the pygmy hippopotamus.The river hippo,shown here,is the larger of the two.It can grow to be 16feet (5meters)long.

The hippopotamus spends most of the hot African days in the water.It can stay underwater for as long as half an hour!Male hippos sometimes fight for territory,using their large front teeth to tear at each other.

This hippopotamus is yawning,but not because he’s tired.A hippo yawns to let other males know that he’s ready to fight if he needs to.

The pygmy hippopotamus is smaller than the river hippopotamus.Still,it can weigh about 600pounds (about 270kilograms).

Little Hippos and Big Hippos