Some of us like a good scratch.
And some of us like to pick our noses.
Fingernails are one of the reasons why
primates are different from
other mammals.
They're like the claws you might find on
other mammals.
Only flattened.
Your toenails only grow half as fast.
But what if one day your nails
stopped growing altogether?
How would this change your life?
Your nails are made of three layers
of keratin.
Keratin cells undergo a form of
programmed cell death
to create the hard form that
makes up your nails.
The three layers start soft
and get progressively harder.
And together, they create
a protective shield.
Human nails have led to
a booming industry of nail care products
and services.
In 2020, the global nail care market
estimated to be worth $2.7 billion.
But nail care isn't the reason we have nails.
Archeologists believe that around
2.5 million years ago,
our ancestors developed broader fingertips.
It was also around that time that they
started picking up stone tools.
But it's still not clear if these two important
evolutionary developments are linked.
Claws are good for scratching, climbing
and digging holes.
But fingernails are critical
for being able to do delicate movements.
Have you ever thought about how you can
separate pages in a book
or pick up small items like a coin?
It's because we have nails.
It might not seem like
nails have much sensation,
but underneath that hard shell
is an intricate network of nerves.
You can grip large things with your hands
and pick up small, thin objects too.
It's a perfect balance.
The evolution of grooming claws
has come from thoughts that
as our nails got smaller and smaller,
we could more easily groom ourselves and
each other.
And that led to more social bonding.
It's cool to think that even now,
getting your nails done
is still a form of social bonding,
which we can trace back millions of years
in our evolution.
But if you didn't have nails,
how would it affect your health?
Well, it would be good and bad.
One of the reasons you have fingernails
is to keep viruses and bacteria from
getting into your body.
So if you didn't have nails,
you would get sick more often.
But that would also mean that
less dirt or bacteria could get trapped
underneath your nails in the first place,
which can cause all sorts of infections.
You'd be surprised to learn that fingernails
have another health-related use.
They work as indicators
for certain health conditions.
Without them, it would be harder for you
to check for sickness immediately.
For instance, peeling nails might signal
an iron deficiency.
Or horizontal ridges on the nails might
indicate kidney disease.
I said might.
Don't listen to people on the internet.
Go to your doctor to seek medical advice.
If we didn't have nails, our everyday lives
would be very different.
Imagine not being able to pick up
small objects so easily.
Or having to be more careful
because you might pick up an infection.
And worst of all,
you might miss out on the joy of
getting your nails done.
And while you're in the beauty salon,
imagine that you didn't have hair
and that everyone was bald.
It's a little hair-raising to think about.
So let's save this story for another WHAT IF.