I recently saw a lot of media hype about the idea the men have more robust jaws than women because pugilism is a natural way of sorting out disputes between our ancestors. I was wondering whether it was worth following this up when I found the blog post The human face evolved to take a punch? Spoiler: no on Evolanth and the associated discussion which highlights some of the weakness of the case.
However one must realize that even if fighting was very rare a human face should not be fatally vulnerable to an occasional punch and I posted the following comment:
The key thing to realize is that humans are not well-endowed with natural protective features - such as horns or a mule-kick. The hand has clearly evolved to be able to punch any attacker with the minimum danger of self-injury. The shape of a clenched fist helps to minimize the possibility of damaging the fingers, with special arrangements to protect the thumb.
The evidence is looking very much as if early humans split into a number of distinct groups which could still interbreed (for example us, the Neanderthals and the Denisovans) and different lines could well have different ways of socially interacting, some possibly involving aggressive male interaction. In the circumstances one would not expect human facial bones to be particularly vulnerable to damage from a clenched fist.
While I feel the paper has overstated its case it makes sense that a human head has evolved so the owner is not incapacitated by a single blow!