# do toenails have any use or are just evolutionary leftovers? **URL:** \ **Category:** Factual Questions\ **Created:** [March 23, 2005, 11:08am UTC](https://boards.straightdope.com/t/do-toenails-have-any-use-or-are-just-evolutionary-leftovers/295869 "2005-03-23T11:08:56Z")\ **Posts on this page:** 5\ **Page:** 2
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [March 24, 2005, 8:43pm UTC](https://boards.straightdope.com/t/do-toenails-have-any-use-or-are-just-evolutionary-leftovers/295869/21 "2005-03-24T20:43:35Z")
> [@](#): > > Splitting the development instructions for hands and toes into different genotypes would require a major and deliberate restructuring of the genotype controlling appendage development. But aren’t there many mammals who have different number of digits on the front and rear limbs? Cats come to mind here, I think. I don’t think that having the same number on each is really a biological necessity. ---
**Author:** ![SpectBrain](https://avatars.discourse-cdn.com/v4/letter/s/a87d85/32.png) [@SpectBrain](https://boards.straightdope.com/u/SpectBrain)\ **Post date:** [March 24, 2005, 9:26pm UTC](https://boards.straightdope.com/t/do-toenails-have-any-use-or-are-just-evolutionary-leftovers/295869/22 "2005-03-24T21:26:42Z")
I recently read, and I’m I sorry I can’t offer a cite, that finger and toenails also aid with tactile sensations, they offer the fingertips and toepads a backstop. ---
**Author:** ![Stranger\_On\_A\_Train](https://avatars.discourse-cdn.com/v4/letter/s/13edae/32.png) [@Stranger\_On\_A\_Train](https://boards.straightdope.com/u/Stranger_On_A_Train)\ **Post date:** [March 24, 2005, 9:47pm UTC](https://boards.straightdope.com/t/do-toenails-have-any-use-or-are-just-evolutionary-leftovers/295869/23 "2005-03-24T21:47:23Z")
> [@Chronos](#): > > But aren’t there many mammals who have different number of digits on the front and rear limbs? Cats come to mind here, I think. I don’t think that having the same number on each is really a biological necessity. Not a necessity, but it would require additional information in the genotype to modify the digits during foetal development, in this case, to retard the development of the tissues that grow the keratin for nails, or the modification to dewclaws in dogs. In other situations, you could simply add another, mostly independent phenotype. The panda’s thumb, for instance, is an extra digit that comes from an extension of an existing bone and is not a part of the specific genotype that forms the rest of the digits. This extra thumb is an advantage to pandas, in that it helps them grasp and tear bamboo, but there is no similar advantage for humans in reducing the number of toes. We don’t need them, or we could at least design something more efficient, but (metaphorically speaking) Nature doesn’t have any reason to spend the time to fix it, just as General Motors doesn’t want to spend the time to make radio dials that don’t fall off after two years.\* Stranger Sorry, couldn’t resist the jibe at my old automotive nemesis, the Chevy Corsica. GM products are much improved these days in terms of build quality. ---
**Author:** ![pravnik](https://avatars.discourse-cdn.com/v4/letter/p/8edcca/32.png) [@pravnik](https://boards.straightdope.com/u/pravnik)\ **Post date:** [March 24, 2005, 10:47pm UTC](https://boards.straightdope.com/t/do-toenails-have-any-use-or-are-just-evolutionary-leftovers/295869/24 "2005-03-24T22:47:33Z")
> [@SpectBrain](#): > > I recently read, and I’m I sorry I can’t offer a cite, that finger and toenails also aid with tactile sensations, they offer the fingertips and toepads a backstop. My physical anthropology teacher in undergrad told me the same thing. By evening out the pressure on the back of the nail, tactile sensation on the fingerpad is heightened. Probably vestigial on the toenail, though, or mostly so. ---
**Author:** ![Amazon\_Floozy\_Goddess](https://avatars.discourse-cdn.com/v4/letter/a/779978/32.png) [@Amazon\_Floozy\_Goddess](https://boards.straightdope.com/u/Amazon_Floozy_Goddess)\ **Post date:** [March 25, 2005, 3:21am UTC](https://boards.straightdope.com/t/do-toenails-have-any-use-or-are-just-evolutionary-leftovers/295869/25 "2005-03-25T03:21:48Z")
> [@badmana](#): > > Having no toes will affect your balance. You might be able to compensate but you’ll always have less balance without your toes. > > I’d imagine that without shoes, and having long enough toe nails, it might offer a little grip when climping dirt/grass hills at speed. I know when I’m running through sand with bare feet my toes “sweep” the sand. With longer toe nails (no longer possible with shoes) it might offer an advantage. \*imagining **Badmana** bootin’ it through the sand barefoot, with huge long creepy toenails… :eek: [Previous page](https://boards.straightdope.com/t/do-toenails-have-any-use-or-are-just-evolutionary-leftovers/295869.md?page=1)