TWO ancient clues may finally solve the mystery of what makes us left or right-handed. Over 90 per cent of people are right-handed - but we have... TWO ancient clues may finally solve the mystery of what makes us left or right-handed. Over 90 per cent of people are right-handed – but we have never understood why. Scientists may finally have cracked the strange phenomenon by studying 2,000 humans... [1949 chars]