NOVA Wonders - First Season

What do you wonder about?

The unknown.

What our place in the universe is.

Artificial intelligence.

Hello.

Look at this, what's this?

Animals.

An egg.

Your brain.

Life on a faraway planet.

"NOVA Wonders"... investigating the biggest mysteries.

We have no idea what's going on there.

These planets in the middle, we think are in the habitable zone.

And making incredible discoveries.

Trying to understand

their behavior, their life, everything that goes on here.

Building an artificial intelligence

is going to be the crowning achievement of humanity.

We're three scientists

exploring the frontiers of human knowledge.

I'm a neuroscientist

and I study the biology of memory.

I'm a computer scientist and I build technology

that can read human emotions.

And I'm a mathematician,

using big data to understand our modern world.

And we're tacking the biggest questions...

- Dark energy? - Dark energy?

Of life... There's all of these microbes,

and we just don't know what they are.

On this episode... The creatures that live on...

We have arachnids living on our faces.

And inside of us... It took 45 minutes

for the larva to come out of my skin.

But could tiny germs actually be good for us?

I said, "Now, these are poop pills?"

Who thinks of that?

It's magic!

It proved that the microbes

were playing an active role

in the shaping our body.

"NOVA Wonders"... "What's Living in You?"

Right now.

Take a look around you... are you alone?

Are you alone?

I don't think so.

The room might look empty,

but I've actually got plenty of company.

She doesn't mean me.

Or me.

Besides them, I...

And all of us... have got trillions of companions.

We're talking about the tiny creatures

that live all over and inside of us.

Microbes... ...like bacteria... ...viruses...

...and fungi.

They're so tiny you can't see them,

but there are more of them in and on your body

than there are stars in the galaxy.

More than there are human cells in your body.

All together, each of us are carrying around

about three pounds worth.

That's about the same size as your brain.

What are they all doing in there?

Today, scientists are exploring this invisible zoo of creatures.

Discovering not only how they can make us sick...

...but how they may keep us well.

It's challenging almost everything we thought we knew

about human biology.

How much power does this microbial zoo

have over our bodies... And even our brains?

I'm André Fenton.

I'm Rana El Kaliouby.

I'm Talithia Williams.

And in this episode, "NOVA Wonders"...

What's living in you?

And can you live without it?

This is a black swallowtail butterfly,

one of the most beautiful North American butterflies.

Harvard scientist Piotr Naskrecki

has studied animals in forests around the world

for more than three decades.

I just found a nest of citronella ants.

They actually smell like citronella.

But bugs are his specialty.

And it was a mosquito like this

that forever changed his view of what was living inside him.

I was in Belize

teaching a course in macro-photography.

And while there, I was bitten a lot by mosquitoes.

After coming back home to Boston,

I realized that some of my mosquito bites

were not really healing, and when I looked closely,

I could see a thin little straw-like structure

that emerges from the wound every now and then

to take a gulp of air.

And being an entomologist,

I realized that this is a breathing tube of a botfly.

Botflies are parasites whose larvae grow on animals

in the rainforests of Central and South America.

Because of their very interesting life cycle,

they are very difficult to see.

The botfly female catches a mosquito in flight

and holds it and glues the eggs to the abdomen of the mosquito.

When the eggs detect the heat of the body of the host,

they immediately hatch,

and then they crawl into the hole

made by the proboscis of the mosquito.

Since botflies never land on their host,

he figured the best way to actually see one

was to raise the larvae to adulthood... in his own body.

Obviously, even me as an entomologist,

I had this initial reaction of slight, slight revulsion.

But that lasted for about three seconds.

And then I thought, "What a fantastic chance

for me to document it and show it to the world."

The larvae spent about three months

growing in the skin of his arm,

until they were the size of large peanuts.

I think the movie "Alien" got it wrong.

A parasite doesn't want to be painful.

Because a victim that's thrashing,

running, ripping things,

is likely to injure that animal that's emerging from his body.

In fact, a botfly actually releases an anesthetic

into his host.

They just pump you with painkillers

so you don't know that you have them,

and they produce antibiotics, so the wound doesn't fester.

It wasn't painful, it wasn't unpleasant,

it was very interesting.

I know it sounds weird,

but I felt an almost... almost father-child relationship

with this organism that was growing in my body.

It took 45 minutes for the larva to come out of my skin.

I prepared a special container,

and sure enough, it dropped into that soil,

in about three or four hours,

it turned into the puparium,

which is kind of an equivalent of a butterfly's chrysalis.

After six weeks it finally emerged.

And though the botfly would only live for a few more days,

its effect has endured.

The experience of having a botfly

made me realize that we ourselves are an ecosystem.

Our bodies are inhabited by a number of organisms,

sometimes permanently or just temporarily.

For some, this lesson might come a little close for comfort.

Would you be interested in seeing your face mites?

No! No?

Michelle Trautwein's research into face mites

is part of the growing trend

to figure out what exactly is living inside us.

My research grew out of this natural shock

that I had when I first heard

that we have arachnids living on our faces.

Oh, wow! There it is.

They have little, like, legs?

Little appendages.

What you're looking at there are his four tiny little claws,

that they use to climb and hang on to your pores.

Here's his long tail here,

which is the perfect shape of a hair follicle.

Even though these creatures live literally under our noses,

we know surprisingly little about their two-week life cycle

because discoveries depend on chance encounters

under a microscope.

Supposedly, they come out of your pores at night,

and the males and females have sex on your face,

then go back down into the pores to lay the eggs.

We actually got to witness the birth of an egg.

It's almost like a third of the size of the mite itself.

It's the only time we have seen it before,

but the truth is that's happening

on every human's face

all over the world, all the time,

which is incredible to think about.

So that's... are they only on your face?

No, no, they're all over.

I don't think there is anything you can do,

in terms of, you know, face washing, showering,

whatnot, that will get rid of them.

We have two different species that live on us,

one a little deeper than the other,

so I like to scrape hard

to make sure I get that second species.

Michelle's trying to build the largest database of mites

and mite DNA ever collected.

You can't see them with the naked eye.

One mite is about as long

as the width of a piece of your hair,

or about a tenth of a millimeter.

Oh, oh, oh, look at this!

You have got a beauty!

Look at that!

That's the best one we have seen all day.

Thank you.

I'm an overachiever. Oh my gosh.

He's probably been eating some earwax there.

They're not just these, you know, bugs on our face.