国家地理:Giraffe: Tall Tale 长颈鹿（在线收听） |
| What do you know about giraffes? Well, you almost certainly know they are the tallest quadrupeds on earth, capable of growing up to 19 feet tall. You may know that this height allows these vegetarians to eat the very nutritious leaves of the acacia thorn tree, here in the woodlands of the Serengeti Plain. They have a large jaw that moves sideways as well as up and down, a well-patterned mouth, and lobed teeth. The teeth comb leaves away from these dangerous thorns. A giraffe can eat up to 75 pounds of food a day and has to eat 12 hours a day to get all the nutrition it needs. The adult giraffe weighs anywhere from 1800 to 2500 pounds. Its huge neck alone weighs 600 pounds. But it has only seven vertebrae, just like yours. Did you know that giraffes only sleep a half an hour a day? They can only put their heads down briefly to drink water. Otherwise their heads have to stay higher than their stomachs, or they risk choky. Now here is an especially rare breed of giraffe, the Rothschild Giraffe. It has white stockings, nope, actually just legs without spots. Giraffes are mostly gentle. If they are hunted, they can either run away from trouble, or they can use those legs to kick. One kick from those six-foot legs can crush the skull of a lion. One final thing I bet you didn't know, about the only thing that needs to defend itself from giraffe attack is the acacia thorn tree. Since their thorns don't deter the giraffes, they've adapted by growing beyond the giraffes' 19-foot reach. |
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