Humanlike grips go back 2 million years: Thumb dexterity gave some hominids an edge in toolmaking

摘要

Thumb dexterity similar to that of people today already existed around 2 million years ago, possibly in some of the earliest members of our own genus Homo, a new study indicates. That finding is the earliest evidence to date of an evolutionary transition to hands with powerful grips comparable to those of human toolmakers, who didn't appear for roughly another 1.7 million years.