8.5: Free Hands
- Page ID
- 62184
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Unlike other primates, hominins no longer use their hands in locomotion or bearing weight or swinging through the trees. The chimpanzee's hand and foot are similar in size and length, reflecting the hand's use for bearing weight in knuckle walking. The human hand is shorter than the foot, with straighter phalanges. Fossil hand bones two million to three million years old reveal this shift in specialization of the hand from locomotion to manipulation.
Chimpanzee hands are a compromise. They must be relatively immobile in bearing weight during knuckle walking, but dexterous for using tools. Human hands are capable of power and precision grips but more importantly are uniquely suited for fine manipulation and coordination.