Yes. Humans have chins, which make jaws weaker. Chins are useless extra bone and essentially a structural defect, but not bad enough for evolution to do anything about.
Doubt, tbh. For one thing, sexual selection is always a viable reason, and for another human jaws are already a fairly vulnerable spot. I don’t think extra bone is a flaw in a species that likes to punch each other in the face in between tripping over rocks and faceplanting because bipedalism is also a skeletal compromise.
Yes. Humans have chins, which make jaws weaker. Chins are useless extra bone and essentially a structural defect, but not bad enough for evolution to do anything about.
Doubt, tbh. For one thing, sexual selection is always a viable reason, and for another human jaws are already a fairly vulnerable spot. I don’t think extra bone is a flaw in a species that likes to punch each other in the face in between tripping over rocks and faceplanting because bipedalism is also a skeletal compromise.
Except sexual selection usually affects one sex, not both. And the extra bone doesn’t make the jaw stronger, it makes it weaker.
Source that extra bone makes a structure weaker?
Source is I heard it somewhere and of course now I can’t find it. :/