Nails, like human hair or the claws and hooves of animals, are made of keratin . New cells are formed in the root of the nail, hidden mostly under the skin. As new cells grow , the “old” ones are pushed out.
According to Wikipedia, the speed with which toenails grow depends largely on the terminal phalanx of the respective finger . That is , the people index fingernail grows faster than the ones of the little finger. Also, toenails seem to grow 4 times slower than finger nails.
The nail itself is colorless and transparent. We see it pink because of the vascularized tissue present underneath. Its color changes in certain circumstances. When you’re cold, nails bruise. Also, if you press on them they turn white as the blood flow on the veins underneath stops.
What are nails made of?
That half-moon you see on the toenail is called lunula. It is part of the root and consists of immature cells. As they grow , they will move to the top of the nail and become transparent. Lunula’s shape, size and color differs from one person to another and from one finger to the other. Lunulas are bigger on the index thumb, for seemingly unknown reasons.
Toenails also have cuticles representing other terminals. Although we get accustomed to cut the thin tissue that covers the nail, it is in fact meant to protect the root of impurities and micro-organisms that enter by it, but also to absorb any shock that might come through.
Have you ever wondered why toenails remain “glued” to the finger? It seems that their lower surface has small bumps and depressions that fit into one another like a puzzle sticking through.
Why do toenails exist?
Perhaps you’re used to them and do not consider them a major advantage. But if you had to live a few days without nails you would realize they do have a purpose. Scientists cannot tell exactly why we have toenails, but there are several theories present.
Some say that the nails are designed to protect the skin beneath them, which is highly sensitive. Indeed, if you’ve ever cut your nails short you realize certainly that which remains exposed skin is sensitive to any touch. However, over time, it gains more resistance. So it happens with those who lose a nail forever. Therefore, opponents of this theory claims that the delicate skin under the nail has emerged in response to the existence of the nail, and not vice-versa.
Another theory which is accepted by most specialists says that toenails exist simply because they are useful, although we do not use them so much as our ancestors used to.
The role of toenails
We use toenails to climb easier on different surfaces when we are barefoot. On the other hand, finger nails are used to clean fruits, seeds and nuts to peel to scratch us to open boxes, etc. . It is true that we would do without them, since we now own various tools such as knives, scissors and more. If we would run out of nails forever, perhaps we’d have a harder time to get used to using them.
Apart from humans, only monkeys have nails, the rest of mammals being “equipped” with claws. It seems that the man left without claws when the upper limbs began to be used for more delicate tasks, case in which the claws would have become puzzling.