Hangnails open up skin and very much killed our non-ancestors. It is a great place for an infection to start. I think it is just a hard problem to solve. Lots of animals have problems with their nails and claws. It is hard stuff poking through / mounted to skin, just a difficult thing to do well.
Lots of animals have problems with their nails and claws
Are you thinking of pets, or also wild animals? I figured part of the problem was that wild animals (and our ancestors) wore down their fingernails and toenails at approximately the same rate that they grow, so they would stay in a good configuration and everything was fine, whereas pets & modern humans have more nail problems because we under-use our nails, grow them out for aesthetics, etc. (But I could be wrong!)
Hangnails open up skin and very much killed our non-ancestors. It is a great place for an infection to start. I think it is just a hard problem to solve. Lots of animals have problems with their nails and claws. It is hard stuff poking through / mounted to skin, just a difficult thing to do well.
Are you thinking of pets, or also wild animals? I figured part of the problem was that wild animals (and our ancestors) wore down their fingernails and toenails at approximately the same rate that they grow, so they would stay in a good configuration and everything was fine, whereas pets & modern humans have more nail problems because we under-use our nails, grow them out for aesthetics, etc. (But I could be wrong!)