Among the Jula (Dioula) people of Burkina Faso, the most peaceful tribe studied, where the murder rate is 1 in 100,000 annually, left-handers make up 3.4% of the population. But in the Yanomami tribe of Venezuela, where more than 5 in 1,000 meet a violent end each year, southpaws account for 22.6%. Faurie and Raymond report their findings in the Proceedings of the Royal Society.The Romans were right. They truly are evil.