Why Humans Walk On Two Legs A team of scientists that studied chimpanzees trained to use treadmills has gathered new evidence suggesting that our earliest apelike ancestors started walking on two legs because it required less energy than getting around on all fours. The five chimps also wore face masks used to help the researchers measure oxygen consumption. While the chimps worked out, the scientists collected metabolic and other data that allowed them to calculate which method of locomotion used less energy and why. The team gathered the same information for four adult humans walking on a treadmill. We were prepared to find that all of the chimps used more energy walking on two legs but that finding wouldnt have been as interesting, Sockol said. What we found was much more telling. For three chimps, bipedalism3 was more expensive, but for the other two chimps, this wasnt the case. One spent about the same energy walking on two legs as on four. The other used less energy walking upright. These two chimps had different gaits and anatomy than their knucklewalking peers. Fossil and molecular evidence suggests the earliest ancestors of the human family lived in forested areas in equatorial Africa in the late Miocene era some 8 to 10 million years ago, when changes in climate may have increased in distance between food patches. That would have forced our earliest ancestors to travel longer distances on the ground and favored those who could cover more ground using less energy. 词汇: chimp )calorie n. 卡,小卡 treadmill n. 踏轮;踏车;单调工作gait n. 步态,步法 knucklewalk v. 用膝关节走路Quadruped n. 四足动物 locomotion n. 运动 1. UC Davis :加州大学戴维斯分校。UC是University of California 的缩写,该校有多个分校,UC Davis是其中一个。Davis以前是UC Berkeley分校的农学院,后来独立出来。Davis是一个大学城,很小的城市,Davis校园基本就构成了这个城市。 3. bipedalism:系bipedal的对应名词,这里后缀-ism表示特征、特性。 1. What did Michael Sockol and his team find out in their study of chimpanzees? B) The evidence why our apelike ancestors came to walk on four legs. D) The evidence why chimpanzees can be trained to walk on two legs. A) While the chimps worked in the lab. C) While the chimps tried to figure out what they should do.-
10部诡异思维异境的影片
十部教你如何花钱的电影
剩女必看:荧幕败犬女王的求爱秘技
学地道英文必看10部的美剧!
北美即将上映的十部惊艳好片
2010英国BBC秋冬剧集宣传片
女王亲临纳尼亚首映 魔法姐妹雪天性感抢镜
10部电影的现实人物原型
重磅推荐:2011年最值得期待的十五部电影
"海扁王"亚伦独爱Cult片 推荐
2010影响世界的50人--詹姆斯.卡梅隆(第30位)
米基洛克《受难记》梅根福克斯演堕落天使
7部有关孤独自闭的电影
莱昂纳多未来几年的新片计划
《卫报》精心之选 电影史上25大喜剧片
英剧:《唐顿庄园》Downton Abbey第4集花絮
不可不看的10部魔幻现实主义佳片
即将上映法国电影最值期待TOP10
魔幻童心:九部奇幻电影
史上最费脑子的10部电影-《时代周刊》
斗心机:12部女人之间的战争
那些真正值得收藏的经典电影 第1辑
2010秋冬最值得期待的电影
15部探讨中年危机的电影
历数十大最佳全裸封面女星
胶片跳动三分钟:品味二十三段绝妙开场戏
盘点《哈利波特》系列十大倒霉人物
GossipGirl第四季第8集剧情预告 诡计妹露馅
影史上十场最让人流连忘返的热吻
靠社交网络推广而票房大卖的10部大片
| 不限 | 
| 英语教案 | 
| 英语课件 | 
| 英语试题 | 
| 不限 | 
| 不限 | 
| 上册 | 
| 下册 | 
| 不限 |