"They found that the structure of the fist provides support that increases the ability of the knuckles to transmit "punching" force."
"force per area is higher in a fist strike and that is what causes localised tissue damage [in the opponent]"
I could have told them that. In this article it states that the force delivered by the open palm and the punch were equal (or at least not greatly different), but that the buttressing of the fist and the boney knuckle protrusions caused the damage.
Surely this is a side-effect of having a fist which can manipulate tools. A serendipitous (well, not for the punched receiver) effect.
Can we deduce that elbows evolved for striking because they're hard and boney?