Primates.
Countless faces.
One extraordinary family.
Right now, across the planet...
..remarkable new discoveries are being made...
Right there.
..about primate intelligence...
OK. Good start.
..their complex relationships...
..and secret lives.
Wow!
Today, over half of the world's primates are under threat.
Our number one objective is zero extinctions.
It's very risky.
The more we understand them...
OVER RADIO: 'We are launching in about 30 seconds.'
..the better we can protect them.
It'd be incredibly sad to lose them.
I have to focus on protecting these mountain gorillas,
because I love them.
Now, more than ever,
it's us that will decide the future...
..for the primates.
Primates are the ultimate social animal.
Living in groups means they need to communicate constantly.
CHIMPANZEE CALLS
None more so than chimpanzees.
Now, ground-breaking research
is revealing that chimps
have a secret language.
Cat Hobaiter has spent 13 years
studying chimps in Budongo Forest, Uganda.
We know that chimpanzees are really vocal.
They're vocalising all the time.
But what I'm really interested in
is a whole other system of communication they have,
which is their gestures.
Gestures are a vital part of human communication.
We use them constantly.
But Cat is the first person to study the use of gestures
in wild chimpanzees...
..and to understand their meaning.
It's essentially like trying to decode almost alien communication,
because you're really starting from scratch.
She worked out a way to decipher this alien language.
The trick is to spot what stops a chimp from gesturing.
If I desperately need a coffee, as I do most mornings,
then, if I'd asked you to pass it to me,
and you passed me a cup of water,
then I would probably ask for coffee again.
If you passed me the decaf, I would definitely ask for the coffee again,
and the one thing that will stop me from asking you for coffee
is when you pass me the coffee.
So that ultimately gets us at what I meant,
what I was trying to communicate to you,
and we do exactly the same with the chimps.
So, by looking at what happens
before and after each gesture,
Cat can work out their meaning.
This is Melissa, who's one of our female chimpanzees,
and her little boy is currently up at the top of this tree.
And then she gives this very obvious little hand raise.
Now, if that was a human,
we do that all the time, right, to get some attention in class?
But for the chimps, it actually means something very different.
So, chimpanzees give an arm raise
when they want somebody else to move themselves.
And in this case, what she wants is her little boy to come down the tree
so that they can move off and find a new feeding patch together.
It can take Cat hours and hours of watching the footage to spot
and decode a gesture.
We've got Jenny and her two young children, so James and Janet.
Jenny walks in front of James
and she looks back at him, and then,
right there, she just kind of shows the heel of her foot
and kind of gives it a little wiggle.
And this foot present gesture, it's not a very obvious one, right?
Once we'd seen it a few times,
we actually worked out that what it means is
"jump on board so that we can travel off together".
Sort of a piggyback gesture.
Cat soon discovered gestures are used
in almost every aspect of chimpanzee life.
We've got the big group of males on the ground here,
and Musa is going to grab a couple of leaves off the nearest tree,
pops them in his mouth, and he starts to tear them.
RIPPING SOUND
And you can hear this very distinctive
sort of ch-ch-ch kind of noise when they do this.
It's called a leaf clip gesture.
This is chimpanzee flirtation.
There is a female chimp who's just up the tree from him,
and this is all about getting the girl's attention.
This is kind of, um, a chimpanzee pick-up line, basically!
Starts to climb down.
And yep, that seems to have done the trick.
A little bit of chimpanzee action going on.
So, just as humans do with language,
there are words that you don't use every day,
so there are words that you might only use on a special occasion
or when you're meeting somebody for the first time,
so we're still picking up these kind of new occasional,
really special gesture types.
So far, Cat has decoded more than 80 distinct gestures.
But there are some that remain a mystery.
Now Cat's research extends beyond the forests of Uganda...
..and she's discovering that there is
even more to chimpanzee gestures.
We're looking at gestural communication
in chimpanzees right across Africa.
What we're starting to see
is that the different groups of chimpanzees
seem to share most of the same gestures...
..but there are subtle differences
in how often they do it or quite how they do it.
It's more like having a different accent, or a different dialect.
This is a crucial discovery.
It supports the idea that different chimpanzee groups
have distinct cultures.
SCREECHING
I am in a race against time
to try and find out about these different cultures
and the communication, because we're losing so many
different groups and populations of chimpanzees every day.
When we're talking about conservation it's not just numbers.
It's about losing
the characters and the cultures and the individuals.
If you lose a whole community,
that's a whole culture you'll never get back.
Imagining the forest without them, it wouldn't be...
It wouldn't be this forest.
Yeah, it would be... It'd be incredibly sad to lose them.
Primates are not just one of the most social animals.
They're also some of the most accomplished tool users.
MONKEY CALLS
This is Koram Island, off Thailand's east coast,
home to beachcombing long-tailed macaques.
They've mastered the art of a particular type of tool use...
..using rocks to crack open shellfish.
Amanda Tan has been observing this unusual behaviour
for seven years.
The tool use in macaques is really, really rare.
You find macaques all over Southeast Asia,
but it's really only a few populations living out on islands
that we see tool-use behaviours.
It's just a culture that's really unique
only to some groups of macaques.
Amanda discovered these monkeys use tools in two distinct ways.
The monkey in front of me here is doing what we call axe hammering.
That's when they use the sharp point of the tool to crack open
oysters that are stuck on rocks.
They also crack open
sea snails and clams and take a pound hammer
to smash that open.
Choice of hammer, and the ability to use it,
have to be learned.
The young ones learn to use tools by staying really close
to the tool users.
When they're really little like that one, they stay close to their mum,
and that's when they get their first taste of seafood.
The beach monkeys seemed like such exceptional tool users,
Amanda wondered if their skills were unique.
Or if they were shared by neighbouring troupes.
So she decided to carry out an experiment.
Just inland, there's another group of macaques
that also have access to a seafood-lined shore.
And so what I'm trying to do is just to put some block of oysters down
with some stones that I collected from the island,
and see if these monkeys know what to do with it.
Amanda wants to test for herself
if these monkeys know how to use the stones as tools.
It's not looking hopeful.
He seemed to pick up a stone
and just sniff it, and not know what to do with it and walk off.
Despite having shellfish nearby,
they don't know they can use stones as tools to get to the food.
It doesn't mean they can't eventually work it out for themselves.
But what would that take?
It's a bit of luck and then a bit of learning.
You need one of the monkeys to be an innovator,
and this behaviour will slowly spread throughout the group
so they learn from each other, sort of a tradition or a culture.
So, once one monkey learns how to use a tool,
they'll all pick up the skill.
For this troupe, it looks like
learning to use tools could take some time.
But, for the macaque groups that can use tools,
life is easier.
But there is a twist to this tale.
On Koram Island, Amanda has discovered
that their highly developed skills are having
some surprising consequences.
By using tools, these macaques
are able to target the largest, juiciest oysters.
And they can get through as many as 40 a day.
We do see evidence
that they are depleting the shellfish on the island.
So, when we compare the shellfish here
versus an island just next to us,
we see that the shellfish here are less abundant
and they're also smaller in size.
This is the first reported case
of a tool-using animal other than us
overexploiting a natural resource.
We know for sure that humans
are depleting the natural resources on the planet
and we never really thought that any other animal was doing it as well.
If these monkeys continue to overexploit their environment,
the shellfish could disappear..
..ironically meaning that this extraordinary tool-using behaviour
would also disappear.
When it comes to surprising new discoveries,
secret language and skilled tool use are just the tip of the iceberg.
In Brazil...
..researchers have recorded female bearded capuchins flirting...
..by throwing stones.
After weeks of pursuing the alpha male,
females catapult rocks at him in a bizarre last attempt
to win him over.
In Central Africa,
remote cameras filmed the first-ever shots of chimps pond-dipping...
..for algae.
During the harsh dry season,
algae becomes a precious and succulent source of food.
And in China,
scientists have just discovered a brand-new primate...
..the Skywalker hoolock gibbon...
..already one of the world's most endangered species.
In the white forests of north-east Brazil...
..researcher Vedrana Slipogor is investigating
the lives of some of the world's tiniest monkeys.
Vama, vama, vama.
SHE WHISTLES
Common marmosets.
One...
..two...
..three.
Vedrana is trying to prove...
Just now, he's looking now.
..that these monkeys have personalities.
And he's approaching.
And then got a bit scared and moved away.
..from the cautious...
..to the curious.
And now Carl is coming.
Identifying personality is harder than it sounds.
Vedrana has devised her own unique way to investigate.
She reveals a strange object
and then records their responses.
As with humans, some humans are more bold
or more shy in a certain situation.
The same thing is with marmosets.
After hundreds of tests,
Vedrana has found each marmoset shows
consistent individual responses.
In other words, they each have
their own personality traits.
Some of them are very explorative
and some of them are not,
but, actually, this is quite interesting,
because this is exactly how they behave in their day-to-day lives.
Having recognised individual personalities,
Vedrana suspects that those different individuals learn differently, too.
Learning is super important in marmoset societies,
because they are highly social.
So it's not only important
for them to learn from their mothers and fathers,
but also from other members of their family groups.
Social learning is crucial for marmoset survival,
from knowing where to find food,
to how to mob predators.
And Vedrana wonders
if certain personalities are better at learning from others.
So she's trialling a new experiment.
The monkeys are given two banana-filled cups,
one black and one white.
The picture of the banana just gets their attention.
This is where it gets complicated.
They're shown a video of a monkey
opening the white cup using its mouth.
Will the marmosets learn from the video,
or do it their own way?
He's looking at the video.
And, does personality make a difference?
Some monkeys do seem to copy the video.
So they managed to open it with the right technique.
The correct cup, as well.
But others seem to ignore it completely.
Tarsilla now came...
..and is manipulating the black box...
..with her mouth.
And she opened it.
Tarsilla is one of the boldest in the group
and she'd much rather work out this task for herself.
Vedrana's research is still in its early days.
But it's clear that even the smallest monkeys
can have a big personality.
Being able to study primates up close
allows us to better understand and conserve them.
But that's not always possible.
This vast, dense network of reed beds surrounds Madagascar's largest lake.
Lac Alaotra spans an area the size of London...
..and is home to a shy and elusive creature.
The Lac Alaotra gentle lemur is the only primate
to live its entire life over water.
This marshland is the only place it can survive.
Malagasy conservationist Herizo Andrianandrasana
has dedicated his life to protecting these vulnerable lemurs.
But out here, his problem
is actually finding them.
We have 23,000 hectares of reed beds here,
so most of them are not accessible.
And that is a challenge.
The reed beds might be huge...
..but they were once much bigger.
They are being cleared for fishing and rice farming on a massive scale.
So Heri wants to know how many lemurs are left,
and exactly where they are,
so they can concentrate conservation efforts.
But in a canoe, it's a near-impossible task...
..which is why he's enlisted the help
of some cutting-edge technology.
It's being pioneered by Serge Wich,
a conservationist with a fascination
for drones.
Drones can show us a visual image that is usually very strong,
and that helps to facilitate conservation.
With him, a group of engineers, astrophysicist
and computer scientist,
all world experts in drone technology.
They've used drones for everything
from mapping archaeological sites
to finding dolphins in the Amazon.
Now, they've come to Madagascar
to see whether their custom-made drone can spot the lemurs.
To have the best chance of detecting the secretive lemurs,
they're using a powerful thermal camera.
It's very sensitive to body heat.
But the lemurs are so small,
no-one knows if the camera will be able to spot them
in such a vast marshland,
so they need to do a test.
Heri, I copy. Over.
Hello, Serge. I copy you.
Heri guides the drone to where he knows there are definitely lemurs.
'We are launching in about 30 seconds. Over.'
'Heri, we're almost there. I'm sure you hear it by now. Over.'
Serge is flying blind, and has no idea what the camera can see.
Heri uses a hand-held camera
to capture a reference of the lemurs' thermal fingerprint
so they can compare.
Yeah, we are on our way back home. Over.
It's only now that Serge will find out
if the drone camera has really worked.
You can quite clearly see three individuals.
So, three in a very tiny spot.
These minuscule dots don't look like much,
until they're matched with the images from the canoe.
Even though it's quite small,
you see it fairly clearly. We even see its tail a little bit.
So we're sure that it's a lemur.
To finally see results is incredible.
That's very helpful for us
to develop a system in the future
that will hopefully be able to detect the lemurs
while we fly over them.
These results could make all the difference.
If the drone can survey the entire lake, Heri can focus efforts
where the lemurs need it most.
The drone can help
better understand the Alaotran gentle lemur and its habitat.
But also, it helps control the illegal activities,
such as the illegal rice farming,
the illegal fishing.
So all of this can be sorted if we have enough information.
There's still a long way to go,
but Serge and Heri have taken an important step
to safeguard the future of the Lac Alaotra gentle lemur.
For some, a passion for primates
knows no bounds,
and world-renowned primate conservationist
Russell Mittermeier is obsessed.
Now he's in Tanzania on a mission.
With 50 years' experience, Russ has a unique perspective
on primate conservation.
And he's witnessed their numbers decline first-hand.
Primates are in a pretty dire situation worldwide.
More than 60% of all primates
are considered either critically endangered,
endangered, or vulnerable.
But Russ believes there is at least one solution.
To me, ecotourism is perhaps the best tool that we have
for ensuring the long-term survival of these animals
and their natural habitats.
When tourists visit wilderness areas in search of primates,
they generate income that's put back into protecting the animals
and their forests.
Now, in his seventieth year, Russ wants to become the first person
to see every kind of primate in the wild...
..inspiring others to follow in his footsteps.
My main objective here in Tanzania
is to see the last of the 79 different types of primates
that exist on the planet.
I'm here to see the kipunji,
which is this very unusual monkey,
and it was not described by science until 2005,
so that's really quite remarkable.
Scientists divide primates into 79 different categories,
known as genera.
The kipunji is in a genera all of its own.
Restricted to just a few forest patches in southern Tanzania,
it's now considered to be
one of the most endangered primates on Earth.
For Russ to find his final primate, he'll need local expertise.
Noah Mpunga and Tim Davenport
are from the Wildlife Conservation Society.
They were the first to report the existence of the kipunji,
and now protect them and their forest home.
Welcome to the camp! Thank you!
Finally we're going to get to see kipunji, I hope!
The weather's got to co-operate a little.
But, shortly after arriving at their forest camp,
things take a turn for the worse.
Severe and unseasonal rainstorms
soon make conditions in the forest treacherous,
and the kipunji much harder to find.
I'm anxious to get out tomorrow. I don't care if it's raining,
I don't care if it's muddy.
Hopefully, conditions will improve by morning.
Dawn...
..and it's not really much better.
But Russ decides to risk it
and get going before the monkeys do.
Local ranger Atu has been tracking the kipunji.
SPEAKS IN OWN LANGUAGE
She saw them yesterday.
OK. It's like 2km.
2km? Yup. OK.
So, presumably they're still there cos it's still raining!
Yeah, could be. Hopefully! We will see.
Russ has been waiting for this morning for years.
But no sighting is guaranteed.
2.29km so far, but...
..it's up and down, up and down.
I can smell them!
While the kipunji can move quickly through the open canopy,
for Russ, the dense undergrowth is near impossible to navigate.
Like most African monkeys, they're very good at hiding!
Oh, wow!
Whoa! Cool!
Wow!
Yes!
Number 79! Good spot!
Been working on that for...49 years!
Oh, yeah, yeah, yeah, yeah. Look at him. Wow!
Funny face!
Funny-looking monkey.
It feels great! I mean, this morning, I'd just about given up
with all the rain, but...
..we got him!
These trackers are amazing. They're really good.
This woman is fantastic.
This is a really special animal.
Russ is the first person to see every type of primate.
But he hopes he won't be the last.
I like stimulating people to go to remote places and...
..engage with the communities,
benefit the local economies.
That's what it's all about.
Ecotourism and primate watching can provide
a new income for local communities
and an incentive to protect primates and their home.
It's clearly demonstrating to local communities the importance of
these intact forests, and the key species that occur within them.
Our number one objective is to maintain
the current diversity of the order primates, zero extinctions.
If we can replicate models like this across the world,
we can save these species from extinction.
Across the planet, dedicated people are going to great lengths
to save the world's most endangered primates.
This orphaned chimpanzee's family were killed by poachers.
Now, he's being evacuated by Virunga's anti-poaching unit
and transferred 400 miles
to a primate rehabilitation centre.
A safe haven where he'll be cared for
alongside other orphans.
In Guatemala, rescued spider monkeys are on their way back to the wild.
Many were originally kept as pets,
requiring five years in rehabilitation.
They're being released together,
a whole new troupe to boost the wild population.
In Brazil, cocoa plantations are providing a new home
for endangered golden-headed lion tamarins.
Much of their natural forest is now gone, but they thrive here.
Locals benefit from the new income...
..and help save tamarins, too.
All over the world, the future of primates is increasingly
in our hands.
Including these charismatic residents
of Malaysia's Penang peninsula.
Dusky langurs.
Their once-pristine forests
are now bisected by busy roads.
To move through their territory,
they must risk crossing amongst dangerous traffic every single day.
Local researcher Jo Leen Yap has seen them run this gauntlet many times.
It's very risky, and you feel your heart ache,
because the infants and juveniles, they will try to cross the road.
And you can see that they are really struggling.
The langurs have found what might appear to be a good solution.
But these are power cables.
They pose a real risk of electrocution.
And they're too thin for the monkeys to balance on safely.
Many struggle to make it across...
..especially mothers and babies.
When the mum and the infant try to cross along the cable wire,
they can't really balance themselves well.
We've got cases of roadkill. All have been below the cable wire.
Jo Leen felt she had to act.
After so many months and years
of looking at them walking along the cable wire,
the things in my heart is trying to help them to cross safely.
Jo Leen knows the monkeys prefer crossing overhead,
so she's decided to install a monkey bridge.
So today is the day we're going to build
the first bridge in peninsular Malaysia
to assist langurs to cross the road.
The team are using upcycled old fire hoses,
much thicker and easier to cross than electric wires...
Ini, ini, ini!
..and hopefully allowing monkeys and other wildlife
to cross between forest fragments much more safely.
As the bridge nears completion,
it seems the monkeys are already keen to check out their new walkway.
Stay here.
Stay here, stay here. Stay here.
So it might take days, or even weeks and months
for them to get used to the fire hoses bridge,
so we just have to hope for the best.
Elsewhere, primate walkways have already been a great success.
In India,
fire-hose ladders have been installed for lion-tailed macaques.
And in Thailand, gibbons take to new crossings with ease.
Given time, it's hoped that these dusky langurs
will soon be crossing safely, too.
The passion people feel for primates
is now perhaps their best hope for survival...
..especially for the world's last remaining
mountain gorillas.
SOFT GROWLING
Their stronghold is the Virunga Mountains.
Innocent Mburanumwe grew up here,
in the Democratic Republic of Congo.
Now, he's the deputy chief ranger
of Virunga National Park,
and he has a special bond with its gorillas.
HE IMITATES GORILLA'S GROWLING
I love to spend time with gorillas.
You know, we consider them like our second families.
This is Nyakamo, a silverback.
He's playing with his son, Balingene.
Innocent has dedicated his life to these primates.
His fascination started at a young age.
The first time I saw the gorillas, I was about 11.
What inspired me to become a ranger,
it's because my father was a ranger,
my brother and my uncle.
Now, Innocent is a world-leading authority on these gorillas...
..and knows their lives intimately.
He's just come to smell me.
Once he touch me,
he just put his hand on his nose to smell.
HE TUTS
These precious moments may seem idyllic...
..but in reality, being a ranger in the Virunga National Park
is one of the most dangerous jobs in conservation.
NEWS REPORT: '..has been extremely intensive...
SCREAMING
GUNFIRE
The park is in one of the most politically unstable places
on the planet.
'Four million people have been uprooted...'
'...village after village destroyed by fighting.
'It's a battle for survival.'
Over 20 years, conflict,
militias, genocide and Ebola have plagued the region.
For those protecting the park, the conflict is a direct threat.
NEWS REPORT: 'The ongoing civil war and poaching have become
'the deadliest threats to the mountain gorillas.'
In 2007, seven gorillas were gunned down.
It was a hard time to see gorillas being killed by people,
like a sabotage.
And it's not just the gorillas that Innocent has had taken from him.
I lost one of my family.
My brother, who died in the line of duty.
Innocent's brother is one of more than 180 rangers
who have been killed protecting the gorillas
and Virunga Park itself.
OFFICER SHOUTS ORDERS
The Virunga park was founded
primarily to protect mountain gorillas.
But it has a role in bringing stability to the region.
In recent years,
tourists have returned, raising precious funds...
..allowing the park to create opportunities for local communities
and oversee the building of schools and clinics.
And all of this helps to ensure the gorillas remain protected too.
In the 1980s, there were as few
as 250 mountain gorillas in the Virunga region.
After years of efforts to protect them, their numbers have now
more than doubled to over 600.
But, for Innocent and his team...
..the battle continues.
I don't want to lose any gorillas.
I have to focus on protecting these mountain gorillas,
because I love them.
The gorillas will need protecting for generations to come.
I have one son who wants to be a ranger like me.
The remarkable recovery of mountain gorillas
is thanks to those who are willing to go to great lengths
to protect primates.
The conservation of the world's primates is a long-term commitment...
..not least because they live such long lives.
The rainforests of Indonesia are home...
..to orang-utans.
An infant orang-utan can grow to live
for another 50 years, or more.
They stay with their mother up to the age of nine...
..learning all they need to survive.
Today, all orang-utans face an uncertain future.
Since 2001,
Indonesia has lost more than nine million hectares
of primary forest...
..much to satisfy
the demand for timber, mining and palm oil.
The equivalent of 1,000 football pitches are cleared every single day.
This destruction means that orang-utans
are in serious need of help.
Signe Preuschoft felt she had to help save orang-utans in need.
These young orang-utans are orphans,
being prepared for a life back in the wild.
So in this forest school programme,
we have a total at the moment of eight orang-utans.
Each vulnerable orphan has gone through the trauma
of losing his or her mother.
And this one here, Gerhana, that's the youngest.
In Gerhana's case, it was just amazing that he would live.
Ja? He was so starved.
He looked like a stick insect!
So it was really touch and go whether he would make it.
Since coming into the forest school programme,
Gerhana, like the other rescued orphans here,
has made a remarkable recovery.
Each is cared for by a dedicated human surrogate parent.
The long-term goal is to release them
into protected forests, and boost wild populations.
But rehabilitation can often fail.
Many orang-utans do not survive in the wild after release.
They often lack vital skills
which they would have learned from their mothers,
high in the tree tops.
The canopy is where orang-utans find food,
shelter and safety from predators.
And that's part of the problem.
There is always a big attraction
for the orphans to come down to the ground.
So, as long as we have many caretakers on the ground,
it's almost impossible to get the orang-utans all up in the trees.
In the wild, orang-utans rarely, if ever, come to the ground.
Signe had an idea.
Their caregivers would have to lead the way...
..into the trees.
James Reed is a highly experienced rope access specialist.
OK, so, this is called the throw line, and this is called
the throw pouch.
HE TRANSLATES
The idea?
If the carers can climb,
then their orang-utans should follow.
Once it starts swinging, lower it down.
There you go.
But some humans find it easier than others.
I have too much rope now!
No, it's OK.
Is it? Yeah, too much is better than not enough.
That's it.
Long training hours are needed to become certified climbers.
But the real test will come
when boisterous young orang-utans are added to the mix.
When the caregivers take to the ropes,
even Gerhana, with a little encouragement,
discovers he climbs like a natural.
Up here, they can really strengthen their climbing skills...
..explore new heights...
..and discover new foods...
..all with the safety of their caretaker nearby.
Signe started seeing a promising change in the orphans right away.
When we first climbed with Gerhana...
..I had never seen Gerhana climb so high as on that day.
This is a positive first step
towards these infants becoming truly at home in the canopy.
As soon as they don't need us,
we just let them go as much as they want...
..and give them the self-confidence,
"OK, I can handle that."
Signe hopes she's giving these orang-utans
the tools they need to survive...
..and that she can release them one day
where they belong...
..in the wild.
Primates...
..are our closest relatives.
They need us now more than ever.
It's only by understanding them
that we can help safeguard their future.
Across the world...
..people are dedicating their lives to finding the answers...
..and making sure the future always has a place...
..for the primates.