Why Am I Left-Handed?
from Aarva Hosted by Natalie Wolchover
If most animals don't favor one side, why are nine out of ten people right-handed? A fetus no larger than a kidney bean begins flailing one arm more than the other weeks before the brain even connects to the limbs. Published on 13 July 2026, the text follows how that tiny, reflexive twitch in the womb eventually shapes everything from ancient combat strategies to the way societies manage hygiene. The search for answers moves through new genetic clues and the "fighting hypothesis" to ask why a ten-percent minority of left-handers persists at all, suggesting that this lopsided trait is a physical record of the human story. Ninety percent of humans are right-handed, a ratio not found in other primate species. Recent genetic research suggests this bias begins in the spinal cord during early development rather than in the brain. These biological origins are linked to the history of hand-to-hand combat, the shift to walking upright, and ancient social taboos. Read at source: Quanta Magazine For more features and details, visit aarva.app
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