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
by looking at their faces.
Happy cat.
Angry cat.
Sad cat.
Or is that the sad cat?
We may not be able to figure out what our cats are feeling,
but can science shed any light on it?
Historically, cats aren't seen
as very expressive.
So there is that idea that they are particularly cold
when it comes to interacting with us.
Compare that to a dog,
whose face seems full of expression...
empathy,
happiness,
sadness,
guilt.
Why aren't cats as communicative?
They're not really able to frown
or have that sad, sort of puppy-dog-eye expression.
They don't seem to have the right musculature for that.
Both dogs and humans have a muscle
that is responsible for raising the inner eyebrow,
which we use for showing things like sadness and concern.
Cats don't have this muscle.
So cats are physically incapable
of having faces as expressive as dogs.
However, Finka's research suggests
that cats can communicate some emotion on their faces.
It's just we don't speak their language.
So, we know that the muscles of the cat's face
are quite different from other species,
and certainly from humans.
They use the muscles in different ways,
and they also have different types of muscles,
and different collections of muscles
will do different things.
Finka studies how cats' faces change
when illness or injury produces pain.
This is the only feeling she can currently say with confidence
that a cat is experiencing.
We are looking at cats when they come into the vet's
with a painful condition,
and we do know
that they're actually changing their expressions
in relation to how they're feeling and if they're in pain.
She has identified a set of incredibly subtle markers
to help track their feelings.
We have a series of 48 facial coordinates.
And we can actually look to see
how these coordinates are altering
based on what the cat's experiencing.
So, whether they're in pain or not in pain,
or whether they're relaxed and comfortable
or perhaps fearful or frustrated.
Finka has identified some telltale signs,
such as a cat's ears turning very slightly outwards and down;
or a tiny reduction in the distance
between the cheeks, mouth, and nose region.
These are all signs
that the cat is not happy and in pain.
But if you think this is going to usher in
a new age of cat-human communication,
think again.
It's very, very subtle.
So, statistically, it's significant,
but in terms of the average cat owner
trying to look at their cat's face,
it might be a little bit more problematic.
Our struggle to read cats' feelings
isn't going to get much easier anytime soon.
But can cats read our emotions any better?
To find out,
researchers conducted a series of behavioral tests.
Because it's quite difficult to test cats,
we know a lot less about their cognitive abilities
compared to dogs.
Doesn't mean
that they don't necessarily have the same level
of skills and abilities.
It just means that it's much harder for us
to find the right context to test them in
and get them to play ball in the way that we need them to.
Pepper the cat has been placed in a room with her handler,
who makes various faces at her.
First up, scowling.
Can Pepper detect this is a negative emotion?
It appears cats are less likely
to react positively to someone they know
if they have an angry expression.
Next, a positive, smiling face.
By running the test multiple times,
scientists gathered results
suggesting that a cat may be more likely
to approach someone they recognize
if they are smiling at it.
What the research suggests is that they are able
to differentiate between our different expressions,
and they're using this information
to change the way that they are responding.
The limited study also suggested that cats react more strongly
to both the positive and negative emotions
of their owners
than to those of strangers.
The behavior of owners is much more important to the cats,
because we're the ones that feed the cats,
and we look after them.
So maybe they're more interested in paying attention to us
for that reason.
We may struggle to read cat faces,
but we're probably less inscrutable to them.
So, what led to this unlikely partnership
between human and cat?
To answer that, it helps to understand their origins.
Domestic cats are part of a much larger and wilder family,
a family with some very big footprints to fill:
the lion, the tiger, the leopard...
predators at the top of their food chains.
But whatever the apparent similarity,
these are not our cats' direct ancestors.
All felines, or felids, evolved from the Proailurus,
an animal living in Eurasia roughly 25 million years ago.
These felids were probably slightly larger in size,
lived more in trees than our domestic cats do.
But otherwise, it's going to have the same teeth and claws,
just like a domestic cat does.
So, all cats, whether you're a lion, a tiger,
or a little domestic cat sitting on your lap,
they're going to have very similar characteristics
that makes a cat a cat.
DNA and fossil evidence tells us that big cats...
the lion, the tiger, the jaguar...
separated from the common ancestor
around 10.8 million years ago.
Large American cats, like the lynx and bobcat,
separated 7.2 million years ago.
The domestic cat's ancestor,
the most recent branch of the felid tree,
established itself 3.4 million years ago...
Felis silvestris, the wildcat.
It's a much smaller subspecies of feline
that relies more on surprise and stealth than brute force.
This explains the origins
of some of the strange behaviors owners see in their pets.
There are several clues in cats' behavior
that they're perhaps not the apex predators,
and, in fact, are prey, as well as predators.
For example, the cat likes to hide,
it likes to conceal itself.
It often likes to be up high, where it feels safe
and where it can be very vigilant.
According to genetic research,
Felis silvestris split into five distinct subspecies:
the European wildcat, the Chinese mountain cat,
the Southern and North African wildcats,
and the Central Asian wildcat.
But which one is the actual ancestor of our domestic cat?
People have been speculating about it for hundreds of years...
about where they came from,
whether or not they came from many different species
or many different subspecies of one species.
In 2007, geneticist Carlos Driscoll
started a groundbreaking study,
collecting DNA samples from wildcats
and comparing their DNA to domestic cats.
With the advent of molecular genetic techniques,
we can really drill down and say definitively
where domestic cats come from.
Each subset of Felis silvestris
has a distinct DNA signature
made up by different combinations
of the four chemical bases, A, T, C, and G.
By comparing these to the domestic cat,
Driscoll was able to pinpoint
which subspecies was its ancestor.
Domestic cats are derived from one single group
of Felis silvestris in the wild,
Felis silvestris lybica.
Felis silvestris lybica,
the North African wildcat...
a solitary animal found throughout Northern Africa
and the Middle East,
longer-legged than our domestic cats,
with a coat that ranges from reddish to grey,
to camouflage in different habitats.
But when did this wildcat become our domestic companion?
In 2004,
on the small Mediterranean island of Cyprus,
archaeologists found evidence of the earliest known encounter
between cat and human.
A team lead by Jean-Denis Vigne
was excavating a 9,500-year-old human settlement.
During the excavation, they discovered a grave...
a grave that had two occupants:
the skeletal remains of a man and a cat,
a Felis silvestris lybica.
It was amazing to find a complete animal,
and especially a cat,
beside a human.
And it was so early that it was really surprising
to have such an evidence of connection
between one cat and one human.
The way the bones were laid out
suggested that the cat had been intentionally placed
next to the man.
They were facing each other in death, in the afterlife.
And this is a, a scene which has been arranged by people.
But what really caught scientists' interest
was the fact that Cyprus is an island,
and no trace has ever been found of native wildcats.
So, how did this cat get here?
The fact that this burial was found on Cyprus
means that somebody brought these cats to the island,
by boat.
The Cyprus settlement
closely matches sites found in Turkey,
so archaeologists believe that's where the settlers originated,
and where we know that Felis silvestris lybica was common.
It suggests these people or their ancestors
must have brought a cat with them.
But the Cyprus cat was different from mainland wildcats
in one very significant respect.
This cat was very big.
This meant that, probably, it has been fed.
So maybe it was more or less a pet.
A larger skeleton indicates
that the cat is domesticated,
because he's getting enough nutrition
that he can devote
all that energy obtained from food
into growth.
Cats in the wild are less able
to spare the energy to grow big.
There's a time cost to hunting.
So, you would have energy diverted
into fueling your hunts,
then therefore, you'll be smaller.
On its own,
the evidence of the Cyprus cat is not enough to confirm
that this nine-and-a-half- thousand-year-old cat
was domesticated.
But there's now evidence from genetic research
that supports this theory.
To date the split between wildcats and domestic cats,
scientists use mitochondrial DNA.
Unlike other DNA,
mitochondrial material comes almost exclusively
from the mother,
so it's passed down the generations unaltered,
except for random mutations that happen at a known rate.
By calculating that rate of mutation,
we can actually calculate the age
of a specimen that we're studying.
So, we use the mitochondrial clock a lot
with different organisms
to try to figure out their age in evolutionary time.
And it shows that our domestic cats split from wildcats
approximately 10,000 years ago...
very close to the time of the Cyprus cat.
Why did it happen then?
Well, at that moment in history,
humans societies were also going through a big transformation...
becoming farmers.
This started in an area of the Near East
archaeologists call the Fertile Crescent.
And Turkey, where the Cyprus cat originated,
was part of it.
The Fertile Crescent was so rich an area
for hunting and gathering
that people could have little encampments
that eventually grew into towns.
So throughout all seasons, they could be in one spot.
This new way of life relied not only
on the ability to grow food, but also to store it.
What's the dawn of civilization
got to do with cat domestication?
Humans by this point were harvesting grains
and caching them,
putting big stores of grains in baskets
in holes in the floors of their houses.
But the grain stores were an easy target
for hungry wild rodents.
They had the potential to devour these new food stores.
Luckily for our ancestors,
this new concentration of rodents
attracted something else... something wild.
Cats were likely drawn into these new human settlements
because they could hear something we couldn't.
Cat hearing is really just truly amazing.
So, they can actually hear very low frequencies
and very high frequencies.
And of course, much of their prey
is squeaking at high frequencies.
Humans can't hear some rodent squeaks at all,
as they vocalize at a frequency beyond our hearing range.
But cats have ultrasonic hearing.
When we hear nothing, they hear this.
The pitch of these squeaks must be lowered by 90%
to make them audible to humans.
Cats also have unique anatomical gifts
that help them zero in on their next meal.
The outside of their ear has an amazing amount of muscles in it,
so they can turn their ear all the way around.
That allows the cat to really hone in
on where the mice are, rats are, where they're communicating,
and hence, they're going to capture them for their meals.
This makes cats rodent terminators...
unstoppable killers.
The allure of easy pickings in the first human settlements...
namely, rodents...
would have been irresistible.
And you'd be forgiven
for thinking that cats still like to show off this prowess
10,000 years later.
She brings us gifts.
Maybe once a month, we have a mouse appear in the house.
It is a bit disgusting.
We get leaves, leaves. Oh, yeah, they brought a leaf in,
and Rita brought a piece of stale toast in once
from the back garden.
So, lots of people think
that their pet cats bring them gifts
in the form of small rodents or birds,
but actual fact, the cat doesn't believe it is a gift.
The cat will often bring home the prey that it has caught
because the home represents the core territory to the cat,
the place that it feels safe.
But 10,000 years ago,
this would have been very effective PR,
proving to our ancestors
that cats protected valuable food resources.
This was a creature you'd want to have hanging around.
Maybe you set out some food for a cat
to keep it around your house.
You might have done that because you thought it was eating mice
and keeping your grain stores clean.
So, the domestic cat split around 10,000 years ago
in the Near East.
But how much have they changed from their wild ancestors?
The wildcat in the wild
feeds only on meat.
They're obligate carnivores, or hyper-carnivores.
So they can only process proteins.
They're metabolically incapable of digesting carbohydrates.
House cats are different.
While wildcats only eat meat,
their domestic cousins have evolved the ability
to digest some plant matter.
The domestic cat, for thousands of years now,
has been living off of scraps...
not just scraps of meat,
but also scraps of grains and vegetables.
And the result of that is that domestic cats
have a slightly longer intestinal length
than their wild ancestor.
And Darwin hypothesized
that this is because the cats are trying to squeeze
as much nutrients out of this poor food as they can.
This irresistible combination of rodents and edible human refuse
could explain why the wildcat decided to come in from the wild
and live alongside humans.
Wildcats genetically predisposed to find humans less scary
would have hung around the settlements.
Anything that has to do with aggression or boldness
are probably genes that are involved
with the actual domestication process,
because those had to change
between the wild progenitor and the domestic cat
in order for the cat to cohabitate with humans.
Breeding between these animals
would have positively selected genes
that allowed them to live more closely with humans.
Certainly, there have been some genes that have changed
between an African wildcat and the domestic cat itself,
because we know the behaviors are different.
Behavioral genes, which are genes
that are involved with our brain and our neurology,
those are genes that have evolved a little bit
to make a domestic cat more docile,
more friendly with humans.
Geneticists have found 13 genes that have changed
in the domestic cat, compared to its wild ancestor:
genes like DCC and G.R.I.A.1,
which are associated with making cats friendlier
and less afraid of people.
We may never know who initiated first contact,
but it's safe to assume
that cats determined the terms of the relationship.
So, it's not a stretch to say
that we didn't domesticate the cat,
the cat domesticated itself.
Genetics has confirmed that domestic cats originated
in the Fertile Crescent,
but it's also revealed something genuinely surprising...
one country had more influence on the genes of modern cats
than any other.
And it was a long way from Turkey.
Egypt.
Professor Salima Ikram is an expert in all things Egyptian,
including their obsession with cats.
The ancient Egyptians really loved animals,
but they also revered them.
Cats were perhaps the most popular
and the most highly venerated,
because of their utilitarian as well as metaphysical values.
In Egypt 4,000 years ago,
the first images of cats start appearing...
wall carvings and paintings of cats living with humans.
Egyptians especially valued the cat's killer instincts.
Ancient texts tell us that not only do cats kill rodents,
but they also kill snakes.
So, of course, the Egyptians love this,
because they were much safer as a result.
Imagine if you're a mother,
and your child is crawling around,
and then a snake approaches, and your pet cat kills it.
Also, for them, the idea that a cat was killing a snake
meant that the sun god Ra was killing the evil snake Apophis.
So, it was sort of doing double duty.
This mystic battle playing out in homes across Egypt
would have done wonders for the cat's PR.
The cat became so important to Egyptians
that they turned it into a goddess.
The cult of Bastet, the cat goddess,
had always been popular in Egypt,
but it really came to prominence 3,000 years ago,
about 500, 600 B.C.
Bastet, the daughter of Ra,
would often take the form of a cat.
Bastet was very much about self-indulgence and beauty
and love and fertility, which was very important.
Unfortunately for cats,
being worshipped as a goddess had a very unfortunate downside.
We're about to go into the tomb of Raia,
who was a New Kingdom official.
It's a really ancient tomb,
and it's not been open to the public for ages.
Wow.
Nice.
They lived
about three-and-a-half thousand years ago,
just at the beginning of the time of Tutankhamen.
But that's not the most interesting thing for me
about this tomb.
For me, the most exciting thing is actually
that it was reused to bury cats in.
This tomb is packed with cat mummies.
The downside of being worshipped as a goddess
was that it led to cat sacrifice on a huge scale.
Pilgrims would buy these cats to give a blood sacrifice.
And so for the cat goddess Bastet,
you would offer up a cat, which would then be killed.
And because it was her titulary animal,
it would attract her attention in the afterlife.
The demand for sacrificial cats became so great,
Egyptians were breeding hundreds of thousands of them.
People were breeding these animals
specifically for sacrifice.
So, we think
that there might have been catteries
scattered all over the country,
where purpose-bred cats were being given to the temples
for the priests to sacrifice.
This breeding program was so intensive,
it may have changed the physical appearance of some cats.
Here, this really sweet little paw,
is part of the foreleg of the cat.
But what's extraordinary is
that you can still see some of the fur here,
and it's a ginger kitty.
And a lot of the cats in paintings are ginger cats.
They were favored,
because they brought out the idea of the sun god Ra,
and you can see this color here.
Seeing a ginger or orange cat today isn't unusual.
But 4,000 years ago, before the Egyptian breeding program,
nearly every cat in the world looked like this tabby.
The striped pattern, which is the mackerel tabby,
was the original "wild-type" version of a cat's coat.
The mackerel pattern helps it to have better camouflage
in the environment that it has evolved in.
Orange coloring isn't good for camouflage.
These cats would have been less well adapted to the wild,
but in the catteries of Egypt,
there was no need for camouflage.
In the wild,
these new coat color patterns wouldn't be tolerated.
They don't provide any advantage.
But when you're around humans,
they become selected by humans,
because they're odd and different.
It's called novelty selection.
So, when we see these odd colorations
showing up in a species,
that is a clear sign of domestication.
The orange mutation may not have occurred first in Egypt,
but it was certainly established and protected here.
So, if it wasn't for the Egyptians,
we may not have orange cats at all.
The intensive Egyptian breeding program
didn't just change the way cats looked.
It changed their behavior, as well.
It's absolutely changing the cat's personality,
making it more domesticated
by putting these cats into large groups.
After generations of selecting for cats
that go from a solitary animal
to being a group species now,
you're probably changing the cat's behavior
to be a less stressed animal,
a more bold and loving animal with humans.
So, Egyptians produced cats that were more attractive to humans.
This could explain why the DNA of Egyptian cats
makes up so much of a modern cat's DNA,
compared with cats from elsewhere.
For any given species,
not all lineages are going to survive.
So for the domestic cat, the Egyptian lineage of cats
really dominated and was more popular,
and so probably out-competed the other different lineages
that were from different places of the world.
But how did cats bred in Egypt spread across the world?
The same way many invading forces did at the time...
by boat.
Egypt was a major trading hub in the ancient world.
Precious metals, gems, and timber came in.
Grain from the fertile Nile went out.
And much of that trade went by sea.
Because the trade ships were filled with grain, primarily,
there were so many rats about,
that, of course, cats were really welcome,
because they not only protected the grain,
but they also protected the sailors from being bitten
and also their own food.
So, cats were really stars on these boats.
Cats began traveling the known world on ships.
For thousands of years, Egyptian, then Roman,
then Viking ships transported cats across the world.
Vikings, in particular,
seemed to have favored the unusual color mutation
that had originated in Egypt.
You can almost map where Vikings were
by looking at the gene frequency of orange in Europe.
Vikings clearly couldn't get enough
of their orange Egyptian cats.
It was probably true
in Viking society,
as it is true in most other early seafaring societies,
that having a cat on board a ship was good luck.
And it could be that the Vikings selected orange cats
to bring on their boats
for some reason that we don't know.
Egyptian cat genes conquered the known world.
But it seems not everyone was happy about that.
Because by the Middle Ages, in Europe,
cats weren't being worshipped...
they were being persecuted, mainly thanks to this man,
Pope Gregory IX.
This 13th-century pope produced a papal anti-cat edict.
It accused cats of being in league with Satan.
And because what the pope said was the word of God,
God hated cats.
The solution to the satanic cat menace
was simple and straightforward...
kill them all.
In late medieval Europe,
there were festivals formed
around the torturing and killing of cats.
And of course, when tortured,
they made, to sadists, a very satisfying amount of racket.
So, what was it
about these relatively harmless furry creatures
that was so alarming to medieval society?
Cats are creepy creatures to a lot of human beings.
So, there's always this tension
between an animal that actually shouldn't be in your home
and is a predator and quite menacing,
and yet is affectionate and cuddly
and purry and furry and warm.
Another reason medieval people could have found cats disturbing
was because of their serpent-like eyes.
Cats have unique adaptations in their eyes
that allow them to be superb hunters at night.
One of these adaptations is
the reflective layer in the back of the eye called the tapetum.
Light entering the eye
is picked up by the photoreceptors in the retina.
It hits the tapetum lucidum, reflects back,
and gets picked up by the photoreceptors again.
This adaptation helps give a cat
six times greater night-vision acuity than a human.
However, this membrane makes the cat's eyes
appear to glow in the dark...
not ideal in the age of witchcraft and superstition.
We are a diurnal species.
We're suited to daylight, we can't see in the dark.
The night for us is disempowering, scary,
and positively dangerous,
whereas to a cat, it is simply a natural environment.
Isn't it, Moses?
By the end of the Middle Ages,
cats had colonized almost every continent on the planet.
And they had started to diverge
further and further from their Near East origins.
One of the more famous and striking of these new cats
was the Siamese.
Siamese cats are very interesting,
because they're sort of a natural breed
that occurred in Thailand.
The Siamese evolved in a different direction
from its Egyptian ancestors,
losing the tabby coloration completely,
opting for something totally unique.
So, this beautiful girl has got a classic Siamese coat color
with the, the browner ears and nose and tail and feet,
and that's the result of a thermosensitive mutation
in a tyrosine gene
that inhibits the production of melanin on these cats.
And so, the warm parts of her body lose the color,
and the cooler parts keep it.
The DNA of the Siamese
show they separated from the Mediterranean breeds
centuries ago
and evolved independently on the other side of the world.
It's not believed that anybody set out to breed these cats.
What happened is, is, a mutation occurred, and it stayed
in this very small isolated population
in Thailand.
And from there, it drifted into fixation
in a certain number of cats.
This process is called genetic drift.
It occurs when a particular mutation
becomes accidentally dominant in an isolated population
that doesn't mix much with the rest of the world.
If a mutation occurs in a small population,
it's got a very good chance of drifting to fixation,
which means that 100% of the cats in that population
will then have that mutation.
The Siamese is an extremely unusual breed,
because its looks result from a natural genetic process.
Most cats in the world arose by more artificial means...
a sudden and huge expansion of cat breeding.
During the late 1800s and into the 1900s and on,
cats have become a status symbol.
Europeans realized that there were different variety of cats
from all around the world.
They then incorporated that into their breeding programs.
People started selecting cats
because they had unique varieties.
The Angora cat came from the Near East;
the Abyssinian came from Ethiopia;
the Manx cat, which had no tail, came from the Isle of Man.
And this new trend of cat breeding
was enthusiastically taken up in the U.S. in short order.
One of the first is the Maine coon,
the natural long-hair cat
that really actually came over with the Pilgrims,
but now was indigenous to the United States.
Another very interesting cat breed
that developed in the United States
is the ragdoll.
This cat developed from cats that were in California.
Breeding, both natural and human-assisted,
has given cat owners an astonishing level of choice.
So, you might think,
that after 10,000 years and all this effort,
we've bred out their wild side.
Apparently not.
These are feral cats.
They are not wild animals, despite how it may look.
These cats, or their close relatives,
were once normal house pets.
Take a domestic cat out of the home,
and they can turn a lot less loving.
Feral cats typically will start up with fight-or-flight
when people come into play.
This suggests all domestic cats have this wildness within them.
So why don't they all turn feral?
The socialization window for cats is very important.
If you want a friendly cat,
a cat that is accepting of people and new experiences,
this is usually between two to seven or eight weeks of age.
If they miss that window,
it's more likely to have a cat that's more fearful
and more what we consider feral.
U.S. cities like Atlanta have a serious problem with feral cats.
We don't want to euthanize a cat,
because you know what happens
when you remove cats from the outdoor environment?
Is that new cats come in.
So, we actually maintain a stable population
so we don't add more cats into that area.
So, veterinarians like Dr. Ashley Randall
work on programs to try and control the situation.
Neutering and spaying is really, really important
when it comes to feral populations,
especially if we're trying to control the numbers.
Any time a population gets really, really high,
you run the risk for disease,
and that's for people and for pets.
Helping Dr. Randall with Atlanta's feral-cat problem
are Lizzy and Kasia from the Pets for Life Program.
We are out today doing some cat-trapping
for what's called TNR... trap, neuter, release.
A female cat
will have kittens every two months,
and she will be impregnable right after she delivers.
So, pretty much, you can assume that every female cat
in the wild out here
is pregnant at all times.
Lizzy and Kasia are tracking a feral cat active in the area.
So they've left a series of traps filled with food.
Well, it looks like somebody's in there.
Yeah.
Hi, there.
Let's see what we've got.
Hi.
Looks like the right one.
We're going to take you to the vet.
Let's get him in the van.
Okay.
On average, they catch 15 cats a week.
It's okay, buddy.
Each receives a welcome health check, vaccinations,
and neutering or spaying.
Okay, so, his heart sounds good.
And his gums are nice and pink.
Very good, big guy.
All right, so we are going to put him on his side,
and then we are going to give him his sedative.
All right.
All we're doing is
taking away the reproductive organs,
so we're taking away organs that they can live without
very easily.
For males, they're up
within about 20 minutes of that procedure.
So he is going to go back outside and live out his life.
All righty, big boy.
The whole procedure takes less than ten minutes.
And a few hours later,
the cat is released back onto the streets.
It's okay, buddy, we're home.
The reason that we trap, neuter, and return feral cats...
versus keeping them and adopting them out...
is, they're truly not happy to live inside with people.
This way.
The vet said
he was pretty healthy, surgery went well.
So he might be a little drowsy this evening,
and then he'll be back to full energy tomorrow,
ready to take on the world.
There you go.
So, domestication may only be skin-deep,
and cats are essentially still wild animals...
wild animals that now live with us.
This essential wildness may explain in part
why cats are not trainable in the way dogs are.
Dogs want to please their owners;
they are what is known as hyper-social.
Cats don't really care what their owners want.
It's a lot more difficult to train a cat compared to a dog
because dogs were specifically selected for their trainability,
whereas cats have shorter attention spans,
and people also really don't spend
a lot of time training cats.
But just because they aren't as cooperative as dogs
doesn't mean they aren't as smart or trainable.
You just have to make it worth their while.
Meet Samantha Martin.
This is Meowy Manor.
Samantha is the manager of a traveling troupe...
or, more accurately, pride...
of performing cats.
Most of the training happens in here.
Cats are brilliant.
People really underestimate the brilliance of a cat.
By training them, they get to use their brain.
They have to figure out what it is that I want from them.
To train her cats,
Samantha uses a method called operant conditioning,
also known as clicker training.
This is the target stick,
so he was trained to jump up
to wherever I pointed the target stick.
And once he had all four paws up on the barrel,
I'd just click and treat.
The clicker acts as a bridge or a marker
to let the cat know that they'd just done a behavior
that's going to give them a reward.
Got it, you got it.
Once the behavior's learned,
I no longer need the target stick or the clicker,
just the prop itself.
And they know what to do with the prop.
So, that's the finished trick.
The question is,
are the cats training to please their owner,
or are they just there for the food?
If you want to train a cat, the great big motivator
is going to be food.
Food is a primary reinforcer.
It's something that they can't live without.
So, most cats can be trained to work for that food.
Compared to dogs, there hasn't been much research
into cat cognition and intelligence.
But cats are clearly clever... when they choose to be.
The Acro-Cats play to full houses as they tour the U.S.A...
audiences crammed with envious cat owners
wondering why their pet won't do this.
Experience and hard work says,
"Reward with food, and you might have a little more luck."
So, where next for our wild feline friends?
Well, some people have plans to completely reinvent the cat.
All domestic cats up until the last 20 years
have been purely Felis silvestris.
Humans have, very interestingly,
now hybridized the domestic cat
with a completely different species.
Anthony Hutcherson has been breeding
one such hybrid... Come on, buddy.
The Bengal cat.
Bengals come from a cross
between domestic cats and a wildcat species
called the Asian leopard cat.
Personality-wise,
they are a little different from other cats,
and they're pretty active and interested and intelligent.
So, if you just want a cat to sit on your lap,
this is not the cat for you.
The difference
between a domestic cat and an Asian leopard cat
is about six million years of evolutionary time.
That's on the same range as the difference
between a human and a chimpanzee.
Bengal adults, 207 through 216.
With such a huge evolutionary difference,
can these new hybrid cats still share our homes?
Come on, buddy.
The challenge lies
in getting those physical traits that attract your eye
and have excited humanity since the beginning of time
without those traits you don't want on the inside:
getting scared easily, peeing in the corners,
you know, needing to eat a lot of raw, bloody meat.
The Bengal is not the only exotic breed
trying to inject a wild look into cats.
The Chausie is a cross between a domestic cat
and another non-Felis silvestris,
the jungle cat.
And the savannah is a cross
between a domestic cat and a serval,
a cat that broke away from the wildcat's line
over eight-and-a-half million years ago.
I think these cats are both the future
and the past of domestic cats.
They represent the thing that people love and want
as a bit of the wild in their house,
which is kind of the oldest reason people love cats anyway.
10,000 years ago,
our first feline furry house guests moved in.
Since then, they've traveled the world,
been feared by popes, and worshipped like gods.
They've hijacked human instincts for their benefit,
apparently learned to read human emotions,
but kept their own feelings under wraps.
They can even entertain us...
as long as we make it worth their while.
And though they've gone through subtle genetic changes,
their wild nature has endured despite our best efforts.
What's more, they've leveraged some of those traits
to become the ultimate consumer pet,
bringing a little bit of the wild
into millions of homes.
And what do cats make of all this?
As usual, they're not saying.
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