The opposable thumb allows them to pick up small items and grip objects from Both sides. Dexterity in the hands and increased Brain size are Believed to have evolved together in humans.
英
美
- 利用拇指和手指可以捡拾小东西和抓握物体。据信,人在演化过程中,手灵巧度的发展与脑体积的增加相关。