Researchers Discover Why Humans Began Walking Upright【研究人员发现人类开始直立行走的原因】
The second study, by Kimberley Hockings of Oxford Brookes University10, was a 14-month study of Bossou chimpanzees crop-raiding, a situation in which they have to compete for rare and unpredictable resources. Here, 35 percent of the chimpanzees activity involved some sort of bipedal movement, and once again, this behavior appeared to be linked to a clear attempt to carry as much as possible at one time.词汇：
chimpanzee n.黑猩猩
ape n.无尾猿;类人猿
注释：
2.ecological settings：生态环境
4.anatomical change：解剖学上的变化
6.Bossou：博苏，几内亚的一个地名。博苏森林生活着黑猩猩群落。
8.increased by a factor of four:增加了四倍
10. Oxford Brookes University：牛津布鲁克斯大学，创立于1865年，是英国最具特色的综合性大学之一。牛津布鲁克斯大学位于世界学术名城牛津。这里学风浓郁、精英荟萃，历来为求学圣地。