Scientists think humans developed right-handedness thanks to these 2 factors
Yahoo • • general
Key Points:
- A new study from the University of Oxford links the predominance of right-handedness in humans to two major evolutionary shifts: bipedal walking and increased brain size.
- Analysis of data from 2,025 primates across 41 species showed that humans stand out due to their larger brains and longer legs relative to arms, traits associated with upright walking and right-hand dominance.
- The timeline suggests early human ancestors began walking upright with no hand preference, but as brain complexity increased for tasks like tool use and communication, right-handedness reached the current 90% prevalence about 2.6 million years ago.
- The left hemisphere of the brain, which controls right-side motor functions and sequential behaviors, likely played a key role in developing hand preference, supported by the role of learning through imitation.
- Evidence from the smaller-brained "hobbit" species, which showed less right-hand dominance, supports the theory that brain size and bipedalism are crucial factors in the evolution of human handedness.