NOVA

They're one of the world's most popular furry pets.

Who's a good kitty?

Famously enigmatic and totally unreadable.

We will often pretend

to know what they are thinking.

Are we right?

Maybe not.

Now biologists and archaeologists

are unraveling their secret histories.

Behavioral genes have evolved a little bit

to make a domestic cat more docile,

more friendly with humans.

Molecular genetics is throwing new light

on the cat's journey from wild animal to furry friend.

We can really drill down and say definitively

where domestic cats come from.

Discoveries in neuroscience are starting to explain

why we find cats so appealing.

It's clear that these auditory sounds

are plugging straight into our emotions.

Behavioral science is giving us a hint

of what they think of us.

They are able to differentiate

between our different expressions.

And why they aren't always the ruthless predator

they sometimes pretend to be.

The cat likes to hide, it likes to conceal itself.

It often likes to be up high, where it feels safe.

What can science tell us about their future?

Humans have hybridized the domestic cat

with a completely different species.

We're on the prowl for "Cat Tales,"

right now, on "NOVA."

Major funding for "NOVA" is provided by the following:

They are as enigmatic today

as when they first came in from the wild.

Cats lead fantastic double lives.

They disappear for hours,

and we don't know where they go.

So, yes, cats are mysterious... they are the best secret agents.

So, where do these strange house guests come from?

These were slightly larger in size,

lived more in trees, but otherwise,

they're going to have very similar characteristics

that makes a cat a cat.

How did they end up living with us?

People have been speculating about it for hundreds of years.

And what about cat intelligence?

Cats are brilliant.

People really underestimate the brilliance of a cat.

Do they even like us?

The right motivation for a lot of cats is not to please us.

Or are they just in it for the treats?

The great big motivator is going to be food.

What is it about these strange creatures

that makes them irresistible to so many of us?

Welcome to Las Vegas for the 40th TICA cat show,

one of the largest feline shows in the U.S.A.

We have 447 cats.

And we have 247 exhibitors.

It is a testament to our fascination with cats.

281 and 282...

Poppy is a Canadian sphinx.

They're a very sweet breed.

They call them Velcro kitties,

'cause they like to be on your lap all the time.

- This is a toyger... - I invented it.

He has a fantastic temperament.

Cats are popular

because they are simply very charismatic,

they're independent, and they're considered easy keepers.

It's nice being able to come home,

relax, have your cat come up to you,

meow, sit in your lap, and purr.

It just makes you feel loved and welcome.

There are over 70 breeds recognized

by the International Cat Association.

He's a white Oriental shorthair,

which is a Siamese in a designer coat.

Yeah, he's a sweet boy.

Then there are glamour cats,

like the Persian, with its thick, luxurious coat;

the Maine coon, large, smart, and a deadly hunter;

and the exotic, one of the most popular breeds in the U.S.

And that's just a start.

You can get small cats, you can get large cats,

you can get cats with shortened legs,

you can get cats with folded ears.

We estimate

about one out of five households in the U.S. owns a cat.

One thing is clear:

owners really love their cats.

Cats are perfect for me, because I just love their companionship.

They jump up on your lap, and that's all I need...

just a little cup of tea and a cat.

Who's a good kitty?

Why are so many people

obsessed with cats?

The latest scientific research

suggests owners literally can't help themselves.

Professor Morten Kringelbach

works at the University of Oxford.

He studies hedonia... pleasure.

Pleasure is probably one of the most interesting tricks

that evolution ever played on us.

It's basically making us do

what it is that we need to do to survive.

To understand how humans experience pleasure,

Kringelbach uses a magnetoencephalograph,

or M.E.G.,

to map and measure

electrical activity in our brains in real time.

What is really exciting about this technique

is that it allows us to basically look

at how the brain is thinking,

how the brain is having emotions.

You can measure over milliseconds

the way that the electromagnetic signals in your brain changes.

And we can start to see

how the brain is unfolding in real time.

The brain fires electrical signals between neurons.

Each tiny electric current

produces a minute magnetic field.

But these magnetic fields are so small,

they can be swamped

by interference from electronic equipment...

even from the magnetic field of the Earth.

For the M.E.G. to measure brain activity,

test subjects must be locked away

in a heavily shielded room.

Okay, we're just about ready to start.

Just sit nice and still and just listen to the sounds.

In previous trials,

Kringelbach's team tracked the brain's responses

to the sound of a newborn baby.

So, what we're seeing here is

how the signal gets into the auditory cortex,

this bit here and here.

It's basically just near to your ears.

And you can see that after about 130 milliseconds,

you get the maximal response.

Now, when you're listening to an infant crying,

you also get activity in the orbitofrontal cortex,

and it's happening at exactly the same time

as when you are actually trying to make sense

of what it is that you're hearing.

The orbitofrontal cortex is central

to processing emotions,

and the experiments suggested that the sound of a baby crying

triggered a response there,

before the subjects

had consciously identified the sound.

It seems to be an instinctive emotional reaction

that may not even require rational thought.

This may be because the need to care for infants

is an essential species-survival skill.

It's clear that these auditory sounds

are plugging straight into our emotions.

In tests where subjects listened to the sound of an adult crying,

a much weaker response arose in the orbitofrontal cortex,

suggesting only certain sounds

trigger a strong emotional response.

But there was another sound that produced the same reaction

as a baby's cry.

A cat's meow.

There seems to be striking similarities

between the way that we process a cat meowing

and that of baby crying.

We get activity in the auditory cortices,

just like we do with anything else.

But before we become conscious of it,

we get activity in the orbitofrontal cortex,

suggesting that this is something

that we need to take care of.

The fact that a newborn's cry and a cat's meow

initiated the same emotional response

could have been a coincidence... except for one thing.

Meowing in adult cats is really interesting,

because it turns out that they only really do it

to humans.

When cats meow to us,

it's as if they are hijacking our emotional responses

to make us love and care for them.

But are they doing it on purpose?

It's not necessarily something that is conscious.

It's just that they know that this works,

just like we know that smiling at our parents worked

when we were kids.

Here, come here, you monster.

They probably don't mean to manipulate us, but they do.

So, we have some idea

of what's going on in our heads about cats.

But will we ever know what's going on in their heads?

I definitely think cats are more aloof than dogs.

I do think they can be very emotionally distant.

We will often pretend to know what they are thinking.

Are we right?

Maybe not, but it's fun to imagine.

Cats are famously enigmatic.

So it's tough to figure out what they're feeling