It’s a good thing that sloths (树懒) don’t have to go to school. They’d never make it on time. These sleepy tree-inhabitants sleep up to 20 hours a day! And even when they are awake, they barely move at all. In fact, they re very slow, and algae (海藻) actually grows on their fur.
Sloths live in the tropical forests of Central and South America, With their long arms and hairy fur. they look like monkeys, but they are actually related to anteaters (食蚁兽). They can be 2 to 2.5 feet long and weigh from 8 to 17 pounds, depending on species.
There are two main species of sloth, identified by whether they have two or three claws. (爪子) on their front feet. The two species are quite similar in appearance, with roundish heads, sad-looking eyes, tiny ears, and short tails. Two toed sloths are slightly bigger and tend to spend more time hanging upside down than their three toed cousins, who will often sit upright in the fork of a tree branch. Three toed sloths have facial coloring that makes them look like they’ re always smiling. They also have two extra neck vertebrae that allow them to turn their heads almost all the way around!
Some scientists think sloths developed their slow-motion lifestyle so they would be less noticeable to hunters such as hawks and cats, which rely heavily on their eyesight when hunting. The algae that grows on sloths’ fur also helps them avoid hunters by letting them mix in with green leaves. They rarely come down from the trees. About once every week, they go down to go to the bathroom, slowly moving about by digging their front claws into the dirt and dragging their bodies. If they are caught by a hunter, sloths will become aggressive, biting fiercely, striking with their claws, and screaming.
【小题1】Who belongs to the same race as the sloth?| A．The monkey. |
| B．The anteater. |
| C．The hawk. |
| D．The cat. |
| A．their arms |
| B．their heads |
| C．their claws on their front feet |
| D．their fur on their bodies |
| A．clean their bodies. |
| B．hunt food |
| C．avoid being hunted |
| D．search for habitats |
| A．Sloths always like smiling. |
| B．Cats dislike hunting sloths. |
| C．Sloths can sleep for a long time. |
| D．Sloths keep calm when facing danger. |
