每年 5 月初，黄石国家公园的开放总能让自然爱好者翘首以盼。作为北美最著名的野生动物栖息地，此时的黄石正从冬眠中苏醒，迎来动物迁徙和繁衍的黄金时期。

Modern life makes us tired, right? But research from societies in Africa and South America suggests people in the ancient ...