In the natural world,
you need to be smart...
..to stay alive.
But we're only just discovering that some animals are brighter...
..than we ever imagined.
I've never failed to be impressed by nature's sheer ingenuity.
Now, brand-new science, using innovative techniques
and the latest technology,
is revealing some surprising brainboxes.
You can get bees to learn almost anything.
Researchers across the globe...
A-ha-ha!
..are uncovering the mind-blowing tricks...
..and clever strategies that give certain species the upper hand...
It is an animal showcasing its intelligence
in front of your eyes.
..as they build their homes...
..navigate their world...
..and raise their young.
It's time to get inside the minds of nature's savviest species.
But I warn you, there's going to be a few surprises
and some controversial candidates.
But most importantly, it's going to give us an opportunity
to learn from these animal Einsteins.
And that's really exciting.
You might think social networking was something only humans did,
but in this episode, we'll look at the clever creatures
that use their social intelligence to get along in groups...
..from friendships that last 50 years
to poking your best mate in the eyeball,
and even cooperating with different species entirely.
Whatever your social life looks like,
we'll show you that for animals,
being together means being clever.
ROAR!
TRUMPET!
CHITTER!
One man...two dogs...
..six ducks.
And the six ducks are part of the training process
for these sheepdogs.
But just look at the energy and the intelligence
and the way that these two separate species, human and dog,
have come together to solve a common problem.
Walk on, Tia. Walk on, Tia.
There's a lot of complex animal behaviour involved
in this cooperation between man and dog...
..teamwork,
the ability to read subtle cues,
friendship, loyalty, hierarchy,
all of those essential components
that are required to form a working social network.
And, in fact, it's the dogs' social intelligence
which has made them man's best friend.
But more of clever canines later,
let's move on to some canny cats.
And I'm talking about big cats.
SNARLING
When it comes to being social networkers who work well with others,
lions are top of the league.
SNARLING
Lions often hunt in groups.
And, just like elite sports teams,
each individual has a particular position to play in the line-up.
Lionesses, called wings, fan out stealthily to surround the herd.
The wings initiate the attack,
driving an individual buffalo towards the centre...
..often, an older and heavier lion
waiting in an ambush position.
Get the tactics right and it's game over for the buffalo.
CHEERING AND WHISTLING
But if you might have to share the spoils,
is team hunting truly better than going it alone?
CAMERA SHUTTER CLICKS REPEATEDLY
Game theory is normally used in the field of human psychology,
but it can be useful in animal-behaviour studies, too,
particularly when it comes to making decisions
about whether animals should cooperate or not.
Imagine that I'm a lonely lion prowling the savannah.
On my own, I can only really bring down small prey.
If I'm lucky, I might be able to kill a buffalo calf.
However, if I meet up with another lion
and we formed a partnership, a cooperation,
then together, we could bring down much larger prey.
Maybe even something as big as an adult buffalo.
The question is, should we form the partnership or not?
So let's think about it on paper, a bit of basic mathematics.
We form a partnership, we get to kill the big buffalo.
Say it's worth ten food units
and the calf worth just two food units.
If we cooperate together and we kill the buffalo,
we get to share the ten, that's five food units each.
It's a pretty good haul.
If we form a partnership and then I defect from it, I cheat,
then I get to kill just the calf,
which is just two prey units, as it were.
And of course, if that role's reversed,
we form the partnership and it defects,
then it gets the calf, the two units, and I get nothing.
And of course, if we don't form a partnership at all
and we're both in competition for just the calf,
then we're only likely to get one food unit each.
Look at that. It's as clear as day.
On paper, the smart thing to do
is to form that cooperative partnership.
And that's what we see in the wild,
with animals like lions, like wolves.
They may be acting individually, selfishly,
but the returns through cooperation are so much greater.
Whether you're a twosome or a whole team,
research shows that the harder an animal is to take down,
the more likely it is that lions will form a coalition to hunt it.
But what does that say about their brainpower?
According to the social-intelligence hypothesis,
the more social an animal is,
the more intelligent it will need to be
to keep track of its interactions with others.
So cats are all solitary and effectively live on their own,
except for lions.
They live in prides and are very social.
And when we think of other social species - elephants, dolphins,
spotted hyenas, chimpanzees -
they're all very intelligent.
So in theory, lions should be the smartest of the cats.
Dr Natalia Borrego wants to know whether being social networkers
makes lions cleverer than other big cats.
To test this out, she's travelled to
the Kevin Richardson Wildlife Sanctuary in South Africa,
where Kevin's unique bond with rescued lions
will give her the opportunity
to get up close and personal with these animals.
But how do you give one of the world's
most fearsome predators an IQ test?
Natalia has designed a puzzle box,
which Ginny the lion must figure out in order to get a food reward.
Ginny has never seen this kind of puzzle before.
Because it's a totally new experience for her,
it's a good test of mental agility. A real brainteaser.
Ginny knows Kevin, but Natalia is safely behind bars.
After 20 minutes, Ginny has figured out
how to pull the door with her paw
and prevent it from swinging shut to allow her to get the meat.
Oh, you're so clever! NATALIA LAUGHS
You are so clever!
Very, very smart, huh?
Good job, Ginny!
Natalia has shown that lions are much better
at solving these kind of puzzles than the other big cats.
But the intelligence test doesn't end there.
Natalia also wants to know if lions can learn by watching one another.
Ginny's pride mate Livy has been watching her solve the puzzles.
Will she be able to copy the solution?
That's it, stay open. Good girl!
It's time to let Livy out.
Let's see what she does.
Oh, she goes to the right side.
THEY LAUGH
KEVIN APPLAUDS
I think...I don't think you can get any clearer than that.
No, that was very good. That was amazing! Very clever girl!
This ability to learn by watching another
is considered a sign of a real animal Einstein.
And Natalia has shown that lions are especially good at it,
outperforming leopards and tigers.
So the experiments went really well, much better than expected.
And it really did show that lions can learn socially from each other.
And it seems that lions are clearly more intelligent
than we've given them credit for.
But if lions need to be brainy to live in groups numbering up to 40,
what about a species that lives in groups of thousands,
or even millions?
And what about when being clever doesn't just mean
knowing when to cooperate with others,
but also having the social skills
to know when to give them some space?
CAMERA SHUTTER CLICKS REPEATEDLY
Sadly, we are now all very familiar
with the concept of social distancing
as a measure trying to combat the spread of a virus.
And it can work, because if you get the distance just right here,
when a disease sweeps in,
you can stop it dead in its tracks.
And we are not the only animal that employs this method.
There is another, which uses it to protect its colony
and also, its collective cognitive ability.
Yes, that's right, it's the ant.
I can't resist it.
Ants are so successful,
there are reckoned to be a quadrillion of them in the world.
That's a million billion.
You can spot them on every continent barring Antarctica,
and you can even find them here, under the paving stones
at the University of Bristol.
Yes, right here!
We have some ants that were just, er...hanging around.
We've got an ant queen who is trying to find a new colony.
This extraordinary ability to thrive in every kind of environment
means they must be doing something right.
But as Dr Natalie Stroeymeyt has been finding out in her research,
it's not their individual brainpower that keeps them alive,
it's their amazing ability to social network.
When you look at a single ant and you just look at its intelligence,
well, it's no different from any other insect.
But the most impressive form of intelligence in ants
is collective intelligence.
So for an ant, being a good social networker
means instead of putting your own best interest first,
decisions are made as a collective,
for the good of queen and colony.
That can mean risking their lives to save other individuals
in order to avoid putting the colony at risk.
Self-sacrifice is rare in nature,
but exists in ants, wasps and bees,
where workers are sterile clones of the queen.
It's most obvious when the colony is threatened with disease.
And to show us how this works, these little creatures
are getting electronically tagged.
The first step is to pick up an ant and get her to sleep.
So we put her in the CO2 bath.
And she'll go to sleep fairly quickly.
It doesn't hurt the ant, she's asleep during the entire procedure,
so it's like surgery.
And she should come back awake within a few minutes.
So then I'll pick up a little bit of glue
and I'll just place a tiny droplet onto the ant's thorax.
And I come and just place the tag in position...
..very softly.
On the left-hand side of the screen is the nest,
with the queen tagged in green
and the nurses that care for her larvae tagged in blue.
And on the right-hand side is the foraging area,
and the red dots are the female foragers.
In the wild, it's the foragers that risk bringing back a disease to the nest.
And Natalie simulates this by infecting one forager
with a microscopic fungus.
First individuals that are contaminated themselves
spend more time outside the nest.
But what we found also was that you had an increase
in the social distance between healthy nurses
and healthy foragers.
It's not known exactly how the ants detect fungal spores,
but pretty soon, the whole colony has changed its behaviour.
The foragers leave the nest,
spending less time inside, where they might transmit infection.
But the tracking software shows they also keep their distance
from one another, reducing ant-to-ant transmission.
And what's amazing is that it's not just the infected ants that do this,
but the uninfected ants, as well.
And that, in a way, is a proactive form of social distancing, if you wish.
They're not contaminated yet, but they are already distancing.
And we think it's a way of decreasing the risk
of epidemics through the colony.
Now, that's clever!
And other critical decisions that may affect the colony
are also made collectively.
Like where to forage and how to overcome obstacles.
The fact that the queen is called queen does not reflect at all
any form of political power or control.
And she certainly does not give any orders whatsoever.
In fact, no ant does.
This is very much a democracy.
When faced with a potentially life-threatening problem,
like the destruction of their nest,
ants crowdsource their intelligence to find a solution.
To show this in the lab, scientists destroyed the ants' existing nest
and set out a range of alternative spaces,
small, dark cavities that might be suitable for a new home.
The options range from this really superb site,
which is clean and made nice and dark with a red filter,
to a really poor nest site,
which is too small and got some dead bodies in it.
An absolute slum.
When the colony is homeless, female worker ants
disperse like a tiny insect team of surveyors, looking for new sites.
When they find one, they'll inspect it thoroughly.
But one ant's view isn't enough.
Like us, they need a second opinion.
If this ant thinks the nest is suitable,
she goes and fetches a second ant,
who will join her in what is called tandem running.
If the second ant also finds the nest to her satisfaction,
she, too, will go and fetch another colleague.
You have a sort of cascade of recruitment,
where each ant is going to lead more ants to the new nest.
It's a typical example of voting with your feet.
And so the numbers snowball,
until eventually, every single ant has relocated.
This collective swarm intelligence
means the colony can solve complex problems with great efficiency.
Everyone should be in awe in front of ant colonies.
And what I would hope is that people would stop asking me,
"How do I get rid of ants in my garden?"
But it's so amazing that I can observe these ants
and then see these trails and see how they work,
and be actually honoured to be having ant guests in your garden,
or in your kitchen.
Now, with their efficient division of labour,
their collective problem-solving ability
and their fluid hierarchy without a central commander,
many scientists think that ants, and not humans,
are the pinnacle of social intelligence.
But of course, across the animal kingdom,
there are far less utopian situations.
There are plenty of animal dictators and tyrants,
even animal politicians,
whose Machiavellian scheming is far more like us humans.
CAMERA SHUTTER CLICKS REPEATEDLY
Chimps are intensely political animals.
And competition to be leader is fierce.
But whilst the biggest and strongest males sometimes do rise
to supremacy, often it's those that master the subtle art
of diplomacy that prevail,
and that means who you hang out with,
literally and metaphorically,
is all-important.
Male chimps use their social networking skills to outmanoeuvre
their rivals in order to gain and retain all the perks
that come with power.
In practice, this often means coalitions between two
or more subordinate males,
who club together to challenge the established leadership,
just like our human politicians.
Well, if human politicians picked parasites
out of each other's fur, that is.
Hopeful leaders will also distribute food,
basically bribes, to win over the masses,
as well as ingratiating themselves
by being extra nice in public.
And there's another parallel between top chimps
and our glorious human leaders.
When support is on the wane, it pays to go to war.
AEROPLANE ENGINE ROARS
History shows us that a timely conflict can improve a failing
leader's approval rating dramatically, by encouraging
followers to put aside disagreements in the face of a common enemy.
It's an idea that we humans know as rallying around the flag.
And our clever cousins, chimpanzees, also appear to know
the value of a well-timed conflict.
CHIMPANZEES SCREECH
Chimps often raid and ambush other troops...
..brutally killing and even cannibalising rival group members.
And taking part in these warlike encounters has been shown
to bring a divided troop closer together.
So when it comes to playing politics,
chimpanzees really are arch manipulators.
No matter how you claw your way to the top in the animal kingdom,
I'm afraid to say that very few females become leaders of the pack.
New research has shown that of the more than 5,000 different
species of mammals, just seven of those that we know of
ever have females that take charge in times of conflict,
when foraging or travelling,
and those that do seem to smash through that glass ceiling,
well, it's their female social intelligence that puts them
in prime position.
The short list includes killer whales, where older females often
dictate the movement of the pod.
And those African lions,
who we've already seen smashing it at teamwork,
actually form female-led prides.
But nowhere is the power of female social networking more evident
than in the complex queendoms of...
..the spotted hyena.
Spotted hyenas live in a unique system.
They live in very large, complex societies.
It's female dominated.
Spotted hyena hierarchies are very strict,
they are very linear,
so you have a really clear ranking of hyenas, one above the other.
As the scientific lead of the Hyena Project
in Ngorongoro Crater in northern Tanzania,
Dr Oliver Honer studies why it is that women are top of the hyena
hierarchy, and it's all to do with power dressing.
'80s throwback time!
The theory behind this dubious trend was that male tailoring could allow
women to enter arenas traditionally dominated by men,
by concealing female characteristics like breasts,
and emphasising male ones, like broad shoulders.
But hyena females don't need shoulder pads
to look more masculine.
They've got something much more effective.
A half-foot-long pseudopenis.
Female hyenas are indeed special when it comes
to their outer sexual organs.
They have masculinised outer sexual organs.
They have an elongated clitoris
that very much resembles a penis of a male.
Female spotted hyenas urinate through this pseudopenis.
They give birth through this pseudopenis,
and they copulate through this pseudopenis.
Talk about multitasking!
While there are other female mammals
where the clitoris looks a bit like a penis, hyenas are the only
ones that actually use it for these purposes,
and all female hyenas have them.
Because of this very special outer sexual organ,
it's really difficult for males to force females to mate with them.
In fact, females have total control over the act of mating.
The male has to assume a very awkward position,
and if she does just one step forward, the male would fall
backwards, and the whole thing is over.
By making mating a female choice,
this unusual anatomy means they already hold power over males.
But according to Oliver's research, there's another thing that's even
more important for female dominance.
And that's the social network.
The social support network is everything that matters
when it comes to hierarchies and social status.
So those that have most social support from their other clan
members, those will rank at the top.
The more allies a female has,
the higher up the pecking order she'll be.
And because top-ranking females get better access to food
than lower females, they'll have more healthy young,
who will add to their numbers of supporters.
But for males, this social support network is less advantageous.
When they reach sexual maturity,
males often move to a new clan where they have no allies.
Their lack of social network as incomers means they have to start
at the very bottom,
and if they ever hope to mate with a female,
they're going to have to grovel.
Males spend a lot of time investing in relationships with females.
They will spend days, weeks following one specific female,
day and night, getting up as soon as she gets up,
staying with her one metre behind her when she walks,
in case she gets interested in him,
he is ready.
With clans numbering up to 100, it takes some serious brainpower
to keep track of who's who in the pecking order.
And spotted hyenas have a particularly enlarged forebrain,
the region involved with complex decision making.
If you consider their social learning skills,
then you would rate them very intelligent.
They have to be aware of each other's social status
and respond accordingly.
So when it comes to social networking, female hyenas
really are animal Einsteins.
Or should that be Marie Curies?
So far, we've seen that social intelligence is pretty
crucial in groups.
But what about the most important social network of all...
..partnership?
How savvy are animals when it comes to picking a mate?
And is brainpower itself an animal aphrodisiac?
In the wild, budgerigars are nomadic birds that call Australia home.
As animals go, they're pretty flashy.
Ooh!
And their bright feathers and complex songs
are something females look for in a mate...
..because they signify healthy genes,
and therefore likely healthy offspring.
But it turns out that's not all women want.
A lot of people think of budgerigars as innocuous children's pets.
I think that's really unkind.
They're very beautiful, charming and interesting little birds.
Particularly given that recently they helped to prove a theory
that Darwin came up with around 150 years ago.
His idea was that female animals, including humans, ought to seek out
intelligence in potential mates,
but although there's indirect evidence for this in the natural
world, it's been hard to prove definitively
outside our own species.
Until the budgies.
Scientists took a female and offered her the choice of two males.
Now, typically, you would think that she would be looking
at their brightly coloured plumage,
size of their territory,
variety of their song,
quality of their display,
not intelligence.
Anyway, she picked a male.
They took the rejected male
and then trained him to solve a puzzle
which demonstrated his intelligence.
They put the birds back together.
She then - guess what?
She switched males,
choosing to spend more time with the cleverer budgerigar.
Proof that female budgies flock to their brighter buddies.
When it comes to who you want in your social network,
it isn't just choosing mates where it pays for animals to be picky.
Some species are also selective about who they choose as friends.
Flamingos can be found in wetlands across the world.
They are extremely social and can live in flocks of thousands,
or even millions...
..group sizes which would make it impossible for an individual
to have a social bond with everyone.
Flamingos can live for up to 30 years in the wild,
and much, much longer in captivity,
meaning that any social bonds they do form can last for decades.
You wouldn't imagine there was that much going on in their flocks.
When you look closer, and you see that they are really actively
avoiding some birds, and they're really choosing
to spend their time with others,
it's amazing how complex their social life is.
At Slimbridge, in Gloucestershire,
behavioural researcher Paul Rose has been studying this flock
of captive flamingos for ten years and has made some surprising
discoveries about their social lives.
So how do we know if two flamingos get along?
It's the animals that are standing, or resting, or doing things together
in the same space that are the friends.
Then, if one bird changes its behaviour,
the other one will go and do the same thing.
Flamingo friendships can be same-sex pairs, or mixed groups of threes
and fours, but the fact they form so consistently and endure
for so long means they must be important for survival.
For a bird that can live into its 80s,
I think these friendships are incredibly important.
These friendships might act as a way of sharing information on the best
foraging and nesting sites.
And also, by reducing squabbling by hanging
out with like-minded pals,
flamingos can save precious energy for the stuff that really matters,
like finding food and rearing chicks.
So sociability is the smart choice for survival.
To be able to process all of that information,
recognise your friends, recognise the birds that you don't really want to hang around with,
that, to me, is really indicative of a higher level of intelligence.
If an animal is going to be social rather than solitary,
it has to make some pretty big decisions about who to spend time
with and who to trust.
Cooperation, whether it's the sharing of resources,
or deciding who to help, well, that comes with a cost.
So, if you're going to give, you want it to be reciprocated.
So the very best animal social networkers are very discerning
about who they put their faith in.
And of all the social species, this group
of white-faced capuchin monkeys in Costa Rica
might just take top prize for inventing
THE most bizarre trust-building exercise.
White-faced capuchins live in groups of up to 20,
in the rainforests of Central America.
Each group occupies a territory of around a square kilometre...
..and will defend it ferociously from rival gangs.
MONKEY SQUEALS
Upon spotting an intruder,
capuchins will give an alarm call...
SQUEALS
..summoning the rest of the group into action.
However, not all capuchins are equally keen to get involved
in a fight, and some will try and hang back without getting spotted
by the braver members of their clan.
So how do these monkeys figure out who they can trust
to have their back?
They've been observed taking part in a rather
grotesque ritual known as eye poking.
Come on, guys, I said EYE poking.
Pairs of monkeys can sit like this with their fingers wedged
into each other's eye sockets for several minutes at a time.
Scientists who have been observing this behaviour for years
believe that it's an odd way of building trust between individuals.
Think of it this way,
if you can trust your eye-poking partner not to rip your eye out,
you can trust him to have your back when it comes to defending
your territory from rival gangs.
And capuchins are not the only things you'll find hanging
around in the tree canopy.
Now, it's one thing putting your life in the hands of a lifelong
trusted friend, another thing putting your life in the hands
of a stranger.
But that's what I'm just about to do.
I'm going to lean back into this arboreal abyss,
many metres from the ground.
I certainly wouldn't want to fall down there.
And yet, I'm going to trust Alistair, here, to lower me back.
Alistair comes with great credentials, apparently.
He's a great ropesmith, a great climber.
He's done all the health and safety.
He's done the risk assessment.
So here goes.
All right, Alistair, lower me back, please.
OK, OK, I think that's far...far enough.
Oh.
You see, we humans have the capacity to do this,
to trust total strangers, something that other species
of animals really struggle to do.
Although, having said that, there is one notable exception,
a species that's found a very curious way to invest trust
in others that it doesn't know at all.
Vampires, the stuff of nightmares and horror films.
For a creature that feeds on nothing but blood,
vampire bats are surprisingly gregarious.
Many people are surprised when they learn about the social
complexity that vampire bats have and the highly cooperative
social lives that they live.
And this South American species is pretty generous too,
as Professor Gerald Carter's recent research has been revealing.
Vampire bats, like many small animals,
are always living on this energetic knife's edge.
They only have one meal a night, and if they miss three meals,
they will starve to death.
And if they miss two meals, they're already very weak.
This vulnerability to starvation means sharing a meal can make
the difference between survival or perishing.
So all female vampire bats regurgitate food
to feed their offspring.
And what's strange about vampire bats is they do this not only
for their offspring, but also other adults, even unrelated adults.
This regurgitated blood is a life-saver for the recipient,
but comes at a cost for the donor.
While you might expect this kind of generosity in nature
within families, helping out strangers is much more unusual.
So there must be something clever going on.
So how do the bats know they can trust a total stranger
to repay them with such a precious resource?
Vampire bats would form grooming relationships before they form
food-sharing relationships.
It is a less risky or less costly kind of social investment.
So if I groom you and you don't reciprocate,
that's not as big of a deal as if I am giving a portion of my food
to you and then you don't reciprocate.
So if two bats are strangers, they show they can be trusted
by giving and receiving grooming before they progress
to giving and receiving vital regurgitated blood.
And the more bats you build these relationships with,
the less likely you are to starve if something unexpected happens.
The individuals who have a wider sort of social safety net are better
able to cope with the loss of, say, a mother or daughter.
And so this social safety net of bats being able to come back
to a roost and receive a food donation from another individual
can be really important for them.
In fact, it's a matter of life and death.
So sharing is a smart move that can literally save the life
of skilled social networkers like vampire bats.
But what about caring?
How clever do you have to be to put yourself in someone else's shoes?
And what's the advantage?
From the time humans are two years old, we start to show empathy
and understanding of what another person might be feeling.
For a long time,
scientists thought that this was a uniquely human trait.
But lately, they've discovered that certain animals could be much
better at reading and reacting to the emotional states of others
than we previously thought.
Prairie voles, which live in bonded pairs,
will go to great lengths to groom and nurture a mate
that's showing signs of stress.
This isn't proof of empathy on its own,
but scientists have shown that this behaviour is triggered
by the same hormone, oxytocin,
that's associated with feelings of empathy in humans,
which suggests a common mechanism for these feelings of caring.
The case has been made for empathy amongst just a few select species,
including dolphins,
primates
and dogs.
But the most moving example comes
from the largest land animal on Earth -
the elephant.
Elephants have complex societies,
with group sizes ranging from dozens
to around 100 individuals, each one of whom can live for up to 70 years.
Long lives and close bonds means that a death,
particularly that of a matriarch, is a traumatic event.
And elephants have recently been observed visiting and caressing
the bones of their departed friends.
This expression of elephant grief makes a strong case for some animals
at least being capable of complex emotions like empathy.
ELEPHANT TRUMPETS
So far, we've looked at social networkers that build bonds
with their own kind.
But for some animal Einsteins, social intelligence doesn't stop there.
They've smashed through the species barrier and learned to interact
socially with members of different species entirely.
Oh, are you tired?
SHE YAWNS Tired.
Time for a little history lesson.
This is Peroni, a spotted miniature horse, one of the smallest horses
in the world, bred for their trainability
and relative intelligence.
Michelle, what else can he do apart from yawn?
Well, he'll toot a horn for attention.
Too-toot.
TOOTS HORN
He's got mine. SHE LAUGHS
Horses form strong bonds with humans and are capable
of being trained to do some amazing tricks.
But what if I told you that there was once a horse
that could count?
In the Victorian era, a German high-school teacher,
Wilhelm von Osten, and his sidekick
Hans, The Clever Horse, persuaded audiences that this was the case.
Not only did this horse seem to have the mathematical capabilities
of a 14-year-old human, it could answer general knowledge questions.
It would tap its hoof once for A, twice for B, three times for C.
The audiences loved it.
They lapped it up.
But the scientific community were rightly sceptical.
So what exactly was going on?
Actually, the horse was demonstrating intelligence,
but it was social intelligence, the ability to read
tiny physical cues his human handler was giving off unconsciously.
So when they were asking those general knowledge questions,
he was looking at the body language, listening to the tone of voice.
And when they got to the right answer, he would stop
tapping his hoof.
Was it a trick, like that demonstrated by Peroni?
Well, yes, it was.
But even von Osten, his owner, wasn't in on it,
because what this horse was demonstrating
was a form of empathetic intelligence second to none.
HORSE WHINNIES
I love the story of Hans, The Clever Horse.
Dr Leanne Proops knows that Hans, The Clever Horse was much
more than a lucky one-off.
The horse is an incredibly social species.
They form lifetime bonds with some individuals
and so, they really need to understand and pick
up on the social cues that they are seeing.
Wild horses live in herds and are known to have strong social
networking skills based on body language.
Along with primates, they're also known to have one of the most
expressive faces of any mammal.
HORSE WHINNIES
Leanne and her colleagues from the Universities of Portsmouth
and Sussex want to know if horses also pick up on the body language
of humans, and crucially, whether they form an opinion
of someone based on their appearance.
To test just how judgy these equids are,
she's going to present the horses with photographs of happy
and angry faces.
Then, several hours later, the horses will meet the person
from the picture in the flesh, and Leanne will be able to see
whether their reaction has been affected by the photo.
It's a bit too well, now he's focused on my hand.
SHE CHUCKLES
So how will we know if the experiment has worked?
Well, for Leanne to decode what these horses could be thinking,
she must consider the crisscross wirings of their brain.
What we know is that threatening things, negative things
are processed in the right hemisphere of the brain and animals
who use their left eye, which transmits information
to the right side of their brain,
to explore negative or dangerous objects,
and that activates that flight-fight mechanism in the right hemisphere.
Conversely, more prosocial and more positive situations
are often processed in the left side of the brain, using that right eye.
So just to clarify, if a horse's eyes are left, it's fight or flight,
and if they use their right eye, then you're considered a good guy.
After a short break for lunch, it's time to introduce the horses
to the real people from the photos they saw earlier.
This time, the person will keep a neutral face
so the horse only has its memory of the photo to go on.
Comet seems pretty relaxed here.
There's no signs of stress or tension.
He's making a few little looks with his right eye,
so that it's a positive experience for him.
He doesn't consider Kate to be a threat in any way.
So this is really what you would expect to see from a horse that's
seen a photograph of an individual looking happy.
And now the person from the angry photo.
He's using his left eye to keep Livvy in focus.
He's activating the right side of his brain.
It's showing to us that Glaze is thinking that Livvy is a potential
threat or a negative person.
He's much less relaxed
than the horses that had seen the happy photograph earlier.
We see these typical displacement behaviours,
these are indicators that they're feeling a little uncomfortable with the situation.
I think we've made our point.
Livvy, I think you can come out now.
It just goes to show that these perceptive equines are watching
and assessing us all of the time, which, now I've said it out aloud,
sounds a little creepy.
Even if you're just passing by the stable, horses are picking
up on our expressions, little cues, and they're really,
as we say, eavesdropping
on how we're feeling and what we're up to during the day.
So horses have expanded their social network to include a different
animal entirely - us.
But what about socialising with the enemy?
Surely no-one in the animal kingdom would make friends with their food.
Geladas are a type of monkey that live in the highlands of Ethiopia.
They're the only primate that eats grass,
plucking it with their hands
and grazing the mountainsides in huge herds.
But what's even more curious than their diet is their relationship
with one of the region's apex predators,
the Ethiopian wolf.
Now, this might look like the start of a typical nature clip...
..and you'd expect it to only go one way,
a way which ends with a baby gelada on the menu.
But just watch what happens next.
For some reason, wolves and geladas
often hang out together.
The wolves don't attack and the geladas calmly let them
walk amongst them.
This unlikely peace pact is so surprising that scientists only
have theories about its origins.
But one idea is that mingling with the geladas may make it easier
for wolves to sneak up on rodents.
And there are some who have suggested that this highly
unusual social network between predator and prey could be the first
step of an even closer alliance -
domestication.
Because there's one very obvious example of a primate and a predator
becoming allies against the odds.
It might be staring you in the face right now as you sit on the sofa
watching this programme.
Woof-woof.
Now, I can tell you that every single breed of domestic dog,
from these collies to my rather pampered poodles,
is distantly related to wild grey wolves.
And long before they were chasing tennis balls, herding ducks
or flopping out to sleep on our beds, we were in intense
competition with their wild progenitors, those savage wolves.
So how did our two species come together and end up with such
a wonderful friendship?
Well, the answer to that question lies in perhaps the greatest example
of social intelligence in the animal kingdom.
The story of how dogs came to be tamed is a bit of a mystery.
Some anthropologists believe that early human hunter-gatherers
actively caught, tamed and bred wolves.
But Dr Juliane Kaminski, from Portsmouth University,
believes they might be BARKING up the wrong tree.
30,000 years ago, we didn't have settlements,
we didn't have houses or anything like that.
So the idea that in all that chaos, we kind of proactively selected
a wolf puppy, took it home and then tamed it to be a cooperative animal,
to me, it doesn't really make a lot of sense.
The idea that's gaining more scientific agreement
is that we didn't domesticate wild wolves and transform them into dogs,
but instead, these clever canines used their social networking skills
to domesticate themselves and made humans their meal ticket.
WOLF HOWLS
Simply by being relaxed around humans, they had access
to more food, and good food, and that kind of gave them an advantage.
The ones that were more cooperative around humans had more offspring.
That means the next generation, then, was, at birth,
already more cooperative, more relaxed.
And so that's kind of started this whole process.
And that's what we call self-domestication.
So perhaps it wasn't survival of the fittest,
more like survival of the friendliest that braided the fates
of our two species together.
And on that journey, these canines changed
in both body and temperament.
Their skulls, teeth and paws shrank, their ears flopped.
They turned into dogs.
And most importantly of all, dogs gained the ability
to raise their eyebrows, something wolves can't do, and not
because they have a sense of irony, but because cute puppy-dog eyes
are scientifically proven to tug on our human heart strings.
This eyebrow movement triggers a kind of nurturing response
because it resembles a movement that humans produce when we are sad.
So if you have 100 dogs in front of you and you quickly have to feed
one of them, you probably go for the one that looks a bit sad.
In fact, when our two species gaze into one another's eyes,
the look of love is so intoxicating,
both humans and dogs release the same chemical - oxytocin -
more usually associated with cuddling our own babies.
Something that has evolved for within-species kind of interaction
suddenly works across species and also tightens
this bond between dogs and humans.
It's remarkable.
And the latest science suggests that dogs' social networking
has been so successful that they've lost some of their wolfish
cunning and instead, learned to solve problems by appealing to us.
I'm about to set my two poodles, Sid and Nancy,
a little intelligence test.
I've got a Perspex box here and inside it,
I'm going to put some of their favourite food.
Guess what? It's sausages.
In we go.
And then I'm going to close the Perspex box like this.
And to be honest with you, I'm being a little bit cruel
because there's no way they're going to get inside this box
for the very simple reason that I've got the key.
Nevertheless, let's see what they do.
Sid, Nancy, come on. Sausages.
Come on.
Come on, Sid.
Your favourite food is in here.
In fact, a bigger pile of sausages than you've seen for some time.
DOGS SNIFF
It's interesting.
They've looked at it, they've sniffed it,
and that's as far as it's gone.
And yet, if their wild ancestor, a wolf, was here, it would be biting
the box, pawing at the box, chewing the box, huffing and puffing
and blowing the box down to get those sausages.
It would demonstrate a persistent intent, that type of intelligence.
But the dogs, I would argue, and I'm a bit biased,
are showing a very different form of intelligence.
You see, dogs have been domesticated for at least 30,000 years,
and in that time they've been living with us,
we've co-evolved together to develop a social intelligence.
And what Sid and Nancy are doing is waiting for me to open the box.
They know I'm going to gaze into their little chestnut eyes
and their little button noses, and I won't be able to resist
using this key.
So they may not be as bright as those wolves any more,
but I'd say they're probably a bit more intelligent in some ways
because they've learned how to access our intelligence.
From mates to mating, reigning supreme over a group,
or self-sacrifice for the good of your peers,
trust, sharing and even mind-reading,
different animals do social networking
in a whole host of different ways.
But none of this behaviour would exist if it didn't offer
an evolutionary advantage.
So if it's smart to be social and it makes you more successful,
then you would expect animal Einsteins to get smarter
and smarter over time.
But what that intelligence actually looks
like can be wonderfully diverse.
It's a triumph for canine social intelligence. I'm giving in.
They're going to get their sausage, which is OK by me.
I've been used as a tool, but do I feel exploited?
Not at all.
Because they get the sausage,
I get the love. Yeah.
There you go, Nancy.
Much better than being a wolf.
That was a bore, wasn't it?
So much nicer to be a poodle, isn't it, Sid?
Quite right.
You beauties.
Beauties.
Next time, we'll be looking at nature's cleverest con artists,
animals that use their brainpower to lie,
cheat and steal their way to success.