From the brains behind brains on, this is the moment of um.

Moment of um.

Moment of um comes to you from APM Studios.

I'm Ruby Guthrie.

Have you ever stopped to think about just how amazing our hands are? They have 27 bones in there. Every person has a unique set of

fingerprints that no one else in the entire world has. We have a poseable

thumbs, which allows us to grasp, pick objects up, and feed ourselves one-handed.

But when you think about it, isn't it kind of interesting that we have these hard little discs

at the end of each finger? And we have to trim them and clean them and some people

choose to paint them. Or even wear fake ones. What's the history behind nails? Have we always had them? I know I can't be the only one

wondering this. Hi, my name is Tanishka and I'm from the Netherlands and I'm

eight years old and my question, why do we have nails?

Hi, my name is Alex Klaxden and I am a paleontologist that means I study animals and people that have been dead for a very long time.

So why do we have nails? Well it turns out we're not the only animals with nails instead of claws.

Also, all primates have nails instead of claws.

And so what is a primate? A primate is us, humans, and apes, and monkeys, and leemers and all sorts of other really cool things.

The question isn't, why do humans have nails, but maybe more like why do primates have nails?

And we don't really know the answer to this, but people have some guesses.

And one of those guesses is that maybe it's an adaptation to feeding on things like fruits and nuts that are all the way

at the ends of branches.

It's called Terminal Branch Feeding.

In order to get to those things, you have to be able to grip those small

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