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Rosemary van Essen Palmerston North, New Zealand

I am not convinced that toenails would be abraded by contact with the ground, as outlined in previous replies. As someone who goes half the year barefoot, walking on a variety of surfaces, I am still required to trim my nails.

Unlike dogs, for example, human toenails remain high off the ground, and I have noticed that people used to walking on rough surfaces also lift their feet higher than town dwellers do. I am not doing as much rough walking as a prehistoric person, of course. But in my experience, to keep toenails short without intervention, you would have to be doing an extreme amount of rock climbing – or stub your toes a lot!

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