[kdlynn (OP)]

i understand how finger nails can be helpful.... but why did humans originally have toenails?

[another_someone]

There is no technical difference between finger nails, or toe nails - in evolutionary terms, they are all just claws.

Living without toe nails can be extremely painful (ok, I suppose with time, the skin underneath will harden up - but then that is all that a a toenail really is - a hard surface over the toe - possibly sharpened, but primarily just a hard protective surface).

[kdlynn (OP)]

i see... i think

[paul.fr]

Toenails are made Keratin.
i know that certain medical conditions can be diagnosed by the state of your finger nails. is this also true of toenails?

[kdlynn (OP)]

good question!

[another_someone]

Toenails are made Keratin.
i know that certain medical conditions can be diagnosed by the state of your finger nails. is this also true of toenails?

If you have any systemic problem (and most significant problems in your body that effect at least one central organ will probably have a systemic component) will effect all parts of your body.

Parts of the body such as toenails, finger nails, and hair, are very good at telling you the history of any systemic problem because they are substantially dead, and so do not change, but are all growing at the roots, and so maintain a history of your bodies state at the time when they were growing - so they can give you a timeline of the history of your health over the period where it has grown (i.e. if you look at you toenail/hair/fingernail at the point where is was growing 4 weeks ago, it will tell you your state of health 4 weeks ago, or you can look further along at the time it was growing 6 weeks ago, and see what you general health was like at that time.  It is like taking an ice core to see what the Earth's climate was like at some point in history.

[Seany]

There is no technical difference between finger nails, or toe nails - in evolutionary terms, they are all just claws.

Living without toe nails can be extremely painful (ok, I suppose with time, the skin underneath will harden up - but then that is all that a a toenail really is - a hard surface over the toe - possibly sharpened, but primarily just a hard protective surface).

Yes.. But if we did not have nails in the first place.. Then it would have just been all skin, rather than a weaker tissue under the nail..

[_Stefan_]

Yes, if the advantage was protection, the entire top of our toes would have a keratin covering, wouldn't they? I'd say they were primarily used as claws.

[Seany]

But when we walk.. We don't need these claws!! Even if we walk on all fours.. We don't need them, do we?

[Seany]

For instance, gorillas scrunch their hands into a fist and walk in fists!

[another_someone]

The pads of no animal are solid keratin, but most mammals have some keratin layer around the periphery, on the upper side of their 4 feet.  Since, aside from humans, and animals domesticated by humans, animals will not need their nails/hoofs clipped, so they must be subject to sufficient natural abrasion as to make this unnecessary, while allowing their continued growth.  Thus, one has to ask whether this level of abrasion, if applied to ordinary skin, would be acceptable; or are the nails required to absorb this abrasion?

It may be that animals mostly do not use the nails in ordinary walking, but to protect their feet when they stub their toes, or otherwise knock their feet against something as they walk.

Ofcourse, humans tend to wear shoes, so we do not wear down our nails naturally, so we have to go through the regular ritual of clipping our toenails (and the same is true of our fingernails - for those of us who do not bite our fingernails).

[paul.fr]

I agree with George, toenails are no longer needed.
I would say they started life as claws and through evolution the need has reduced to such an extent that i believe they will soon (evolutionary, soon) cease to be. This may upset some girlies, but also cut down on the expence of nail polish.