From a new paper:
Left-handedness is associated with greater fighting success in humans
Thomas Richardson, R. Tucker Gilman
Left-handedness is a costly, sexually dimorphic trait found at low frequencies in all human populations. How the handedness polymorphism is maintained is unclear. The fighting hypothesis argues that left-handed men have a negative frequency-dependent advantage in violent intrasexual competition giving them a selective advantage. In support of this, many studies have found that left-handed men are overrepresented among modern professional fighters, but studies typically find no difference in fighting success between left and right-handed fighters. We studied over 13,800 professional boxers and mixed martial artists of varying abilities in three of the largest samples to test this hypothesis to date, finding robust evidence that left-handed fighters have greater fighting success. This held for both male and female fighters, and for both percentage of fights won and an objective measure of fighting ability. We replicated previous results showing that left-handed fighters are strongly overrepresented in professional combat sports, but left-handed fighters did not show greater variance in fighting ability, a hypothesis suggested in previous studies. Overall we find strong evidence consistent with the fighting hypothesis.
It’s not clear if left-handers tend to be overall better fighters or if they just enjoy an advantage from being in the minority and thus their opponents are less familiar with their style of fighting.
[Apollo is looking thru a book of Philadelphia fighters]
Jergens: What exactly are you looking for Apollo?
Apollo Creed: This is who I’m looking for. The Italian Stallion.
Jergens: Rocky Balboa? Never heard of him.
Apollo Creed: Look it’s the name, man. The I-talian Stallion. The media will eat it up. Now who discovered America? An Italian right? What better way to get it on than with one of its descendants?
Apollo’s Trainer: He’s a southpaw [lefthander]. I don’t want you messing with southpaws. They do everything backwards
Apollo Creed: Southpaw nothing. I’ll drop him in three. Apollo Creed meets the Italian Stallion. Now that sounds like a damn monster movie.