While left-handed people may have had an advantage in fighting, they were also more likely to be mortally wounded due to the position of the heart.
Researchers from a University in Sweden and Chester University in the UK propose that the heart’s location in the left hemithorax makes the left side of the chest vulnerable to a fatal blow during combat.Whichever hand holds the weapon changes the way the chest is exposed in battle. A left-handed grip rotates the left side of the chest towards the opponent, leaving the heart exposed.On the other hand, a right-handed grip rotates the heart away from the opponent, reducing the risk of a fatal blow.Although lefties may be better fighters, their disadvantage in combat could have resulted in a smaller left-handed population.The study suggests that early ancestors who preferred using their right forelimb in combat had a lower risk of a mortal wound, giving them a fighting advantage and leading to a greater frequency of right-handedness.While this is still a hypothesis based on speculation, it sheds new light on the longstanding mystery of why most people are right-handed.The study provides an intriguing insight into the role of combat in shaping human evolution and raises further questions about the nature of human asymmetry.