(captivating music) ♪ (narrator) Giant nests in trees... ♪ ...mountains as tall as houses, widespread tunnel systems below ground.

In the African Savannah, building a home requires creativity.

Sociable weaverbirds build community nests weighing tons, accommodating hundreds of the same species.

Aardvarks burrow their home underground in the Savannah's basement.

♪ Tiny termites are the architects of these skyscrapers... ♪ ...but they do not live alone here.

Strangers move in too.

Are they just taking advantage of the builders?

♪ Or do the sub-tenants and builders benefit from their coexistence?

What do they accomplish together that they could not do alone?

Each resident contributes, more or less, to their animal flat shares.

♪ (birds chirping) (lighthearted music) ♪ This sociable weaver is looking for the perfect construction material.

♪ Green and flexible leaf strips are needed for the threshold, but they're tough to get.

♪ The brown and dried strips are much easier to find.

They are used to build the rest of the apartment.

♪ (birds chirping) ♪ But not all weavers have mastered their craft yet.

♪ (birds chirping) ♪ And so, a whole lot of material falls to the ground.

It can be recycled, though... ♪ ...not only by other weavers.

In the Savannah, nothing is wasted, a true paradise for harvester termites.

These insects consume vast quantities of dried plant matter.

How fortunate that their food source and underground nest are only a short distance away.

♪ The construction expert has found a matching strip.

♪ It's needed for the facade.

Here we go.

Unlike other weaverbirds, the sociable weaver does not weave its nest, it stacks it.

♪ Rather unusual, the nest is built from top down.

The roof lies on the supporting branch and carries the weight of the entire construction underneath it.

The house entrance is at the bottom, making it difficult for intruders to access.

♪ Almost done.

Just a few more sharp strips are needed at the end.

These function like small lances and help to fend off enemies.

Under the giant nest, stalks are beginning to run low for the termites.

(anxious music) A scout is sent off.

♪ It's on a mission to seek out a new food source.

♪ Target located.

If she mobilized the colony, this would mean the end for this giant nest.

The termites could eat it all up.

The whole construction would fall apart.

♪ (crunching) The weaverbirds wouldn't stand a chance against an invasion of harvester termites.

Lucky for them, they have flatmates.

The praying mantis could prevent the tragedy.

One of its responsibilities is to get rid of pests.

It's only waiting for prey.

(tense music) But unfortunately, for a juicier one.

♪ The termite quickly crawls back down again to get help.

♪ But there's another, more attentive flatmate, who wants to keep the house clean.

(rustling) (menacing music) The Kalahari tree skink.

♪ (crunching) It saves the co-living space from an invasion of the termite.

(birds twittering) No wonder there's a Kalahari tree skink in almost every weaver colony.

It lives there for free, in exchange for its concierge services.

(birds chirping) On the neighboring tree, there's a new applicant looking for a place in a flat share.

(birds twittering) (ominous music) ♪ The smallest of all falcons does not build its own home.

♪ The pygmy falcon is a squatter.

♪ (birds chirping) It just occupies the place, regardless of the owner's opinion.

(rustling) (birds chirping rapidly) The weavers' protest doesn't bother the falcon in the slightest.

The bird knows that it's way stronger.

(birds chattering) ♪ The Kalahari tree skink hasn't noticed its new roomie yet.

This could be fatal, as the pygmy falcon never misses a meal.

Truce isn't part of its vocabulary.

(tense music) And so, the weavers' hero ends up as a meal.

(insects buzzing) (birds chirping) Pygmy falcons squat and eat up heroes.

But can they also contribute to the living community?

(birds chirping) The sociable weavers are tired.

They return to their safe and comfortable nest, as they do every night.

Unlike other birds, these weavers use their nests throughout the whole year, not only during breeding season.

(enchanting music) ♪ It's now time for the aardvark to leave its dugout.

(placid music) ♪ Aardvarks spend most of their time digging for food and shelter.

And as they like to switch to another residence every night, there is a lot of digging to be done.

♪ (scraping) Powerful claws, tapered ears, and a muscular body help them burrow through the concrete-like ground of the Savannah.

(scraping) ♪ The full extent of the digging activities doesn't become visible until the next morning.

(bright music) ♪ Countless burrows on an area as big as a soccer pitch could ensure housing for all, all who like basement apartments, like the warthog.

While the aardvarks stay at home and sleep the day away, the warthogs roam around.

(warthogs barking) (warthog groaning) (tense music) But young warthogs are a highly coveted prey.

♪ Even hyenas can't resist going after them, and they are usually scavengers.

(grunting) Luckily, they find refuge in an aardvark's burrow.

For now, they are safe.

(calm music) ♪ (warthog grunting) Not only mammals benefit from the aardvark's excavation activities, but also birds.

The little bee-eater usually carves out its nest in the slopes of riverbanks, but the walls of an aardvark's burrow are also suitable.

There, the little bird can dig its nesting tubes up to a depth of two meters, even into the dry and level ground of the Savannah.

(bright music) (bird tweeting) In the pitch dark of the nest, a chick is hatching.

An infrared camera, invisible to the birds, unveils it all.

♪ The siblings, only a few days old, have crawled in the back of their home.

♪ (bird cheeping) ♪ Once hatched, the newborn must immediately be fed in order to keep up with its older siblings, but the darkness makes it difficult to find the right beak.

She's getting tired of searching.

♪ Next time.

♪ (wings flapping) ♪ Bee-eaters hunt for insects in flight.

(birds chattering) This small bit is for the partner, though, as a sign of love.

(birds chattering) (wings flapping) Finally, the chicks are to get their fair share.

But, as always, one has to carefully remove the sting first.

(wings flapping) (bird chattering) At last, the little one gets to eat.

Finding the beak is no challenge this time.

It rather seems like letting go is the harder part.

(bird chirping) Feeding, cuddling, taking care of the rest of the eggs, tidying up, there's quite a lot going on in the bee-eaters' apartment.

(insects buzzing) Deeper down in the burrow, the aardvark is oversleeping.

(serene music) ♪ She's exhausted.

♪ (rhythmic exhaling) ♪ After a gestation period of seven months, she just gave birth to one single cub.

♪ (suckling) ♪ Aardvark mothers are single mothers.

These two will spend the next six months together.

This can be quite demanding at times.

♪ As the sun goes down, the mother aardvark wakes up.

She needs to find food.

Her young has to stay home alone.

(enchanting music) ♪ Cape porcupines inhabit the side chamber of this co-living space.

They have also woken up, and are now setting off to find food.

(lighthearted music) ♪ Bats... ♪ ...cape porcupines... ♪ ...and aardvarks all share the same underground living space.

Each resident extends the space and builds its own side chambers.

In this way, they create the giant underground housing estates of the Savannah.

(curious music) ♪ From the outside, termite mounds don't look like the most suitable place for a flat share, although they're huge.

♪ But a look inside reveals that there is enough room for quite a few subtenants.

♪ The vascularized ventilation system of termite mounds offers housing space for many species, except for the termites themselves.

They live under the mound, below ground level.

Whenever repair work needs to be done, they come up.

(lively music) ♪ The busy workers use their saliva, feces, and sand to build the concrete-like mound.

Once the mound is dried, it's rock-hard and weatherproof.

♪ Termites live underneath the walls of their mound to protect themselves from daylight and enemies, and hence, to serve their queen.

But their concrete castle is also used by others.

(upbeat music) Dwarf mongooses have decided to move into this mound.

The smallest of all African carnivores almost exclusively live in termite mounds and love to sunbathe on their roof terrace in the early morning.

No wonder they like this apartment!

The termites have kept it pleasantly warm overnight.

But the mongooses are bad flatmates.

They ruthlessly mess up the place and won't even pay a single dime.

After all, the owners are going to fix the mess, aren't they?

Some of the termites even end up as a snack.

How impolite of the mongooses to eat their own landlords!

♪ But still, the termites must quickly repair the damage, otherwise, they risk being attacked by their enemies.

(threatening music) A Matabele ant has spotted the open mound.

It has targeted the termites.

The dwarf mongoose couldn't care less, and so the termites have no one to protect them.

♪ The Matabele ant makes short shrift of the termites.

A race against time has started.

(tense music) The termites must repair the damage as fast as they can.

The ant is already mobilizing its fellow colony members, telling them there's food in abundance... ♪ ...and they're coming in swarms.

♪ Only when the last hole is being closed, will the termites be safe again.

♪ (termites scuttling) ♪ Finally, their fortress is secured.

♪ As their queen is very fertile, termites can easily make up for the loss caused by such attacks.

It's just the work that they are left alone with.

(easygoing music) ♪ The pygmy falcons, that haven't exactly won friends while squatting in the weavers' residence, have become parents to three hungry chicks.

(birds chirping) Lizards are on today's menu.

They're being delivered for free, and straight to the white entrance of the elegant accommodation.

(birds chattering) The builders of this shared apartment are also raising their offspring.

(birds screeching) ♪ Many young are peeking out from their nest.

(birds screeching) Loudly and relentlessly, they're screaming for food.

(birds screeching) (wings flapping) (bird chirping) The pygmy falcon's offspring is already grown.

Time to move out of the room and leave the shared flat.

The parents try to lure the young with food.

For the youngster, the handing-over of the prey becomes a balancing act... (birds chirping) (insects buzzing) ...and the parent falcon is not exactly making it easier for its young.

(wings flapping) (birds chirping) But, it was worth the effort.

(birds chirping) How difficult it is to fly with a full stomach!

This one is not very good at it yet.

That's dangerous, because on the ground, there are many enemies.

It's better off hurrying back into the nest.

(wings flapping) (birds chirping) But even here, it's not 100 percent safe for the offspring.

(tense music) ♪ A slender mongoose has sneaked into the giant house of the weaverbirds, and it's hungry.

♪ The sociable weavers can't do anything about it on their own.

They need help because the mongoose is a serious threat to their offspring.

Only a fifth of the brood makes it to adulthood, and the mongooses are partly to blame for this.

♪ (wings flapping and birds chirping) ♪ Time has come for this unpopular flatmate.

(bird trilling) The pygmy falcon also fears for its young.

But unlike the sociable weavers, the falcon has sharp claws and a sharp beak.

With mock attacks, it manages to chase the mongoose off the tree.

(intense music) ♪ (dirt scattering) ♪ (birds chirping) In the end, the pygmy falcon did contribute to the shared flat as a protector for the good of the offspring of the whole community.

(crickets chirping) Some months later, in the aardvark flat share.

As usual, the mother leaves the house at night.

(calm music) ♪ Her young is now big enough to follow.

♪ But the aardvark mother is quickly going off.

She wants her young to learn how to get by on its own.

♪ The youngster has gained quite some weight in the past half year, but it is still hesitant.

First, it needs to check things out carefully.

♪ (sniffing) ♪ An aardvark's snout is its most important organ.

♪ It can sniff out food from several meters underground, food like ants or termites.

♪ (blowing) Just below the ground's surface, this young aardvark has found some ants.

(scratching) (blowing) A few air blows from the nose expose them.

Together, with a whole lot of dust, they are pulled into the mouth and crushed.

(crunching) (bird calling) (scratching) (grass crunching) Termites are more difficult to come by.

(blowing) Their mounds have to be broken down forcefully.

The aardvark can then capture the delicacies by extending its tongue, which can be up to 30 centimeters long.

Trapped in sticky saliva, the termites disappear in no time.

But the aardvark never eats up all termites.

It manages resources sustainably.

And the other animals in the Savannah benefit from this.

(upbeat music) Ant-eating chats, for example, they, too, live in the aardvark's shared flat.

Just like the little bee-eater, they build their own apartments into the walls of the burrow.

However, the bird and the aardvark also come together outside their shared flat.

This ant-eating chat is looking for a specific termite mound.

♪ And this is whom it has to follow.

♪ In winter, the aardvark needs to start the search for food already in the afternoon because the nights are cold, and the termites have dug themselves deeper into the ground.

From the outside, the insects can now barely be seen, a problem for the ant-eating chat.

Fortunately, there is the aardvark.

♪ It leaves the termite mounds completely destroyed, a culinary feast not only for the ant-eating chat.

(birds chirping) ♪ The battle for food is decided.

The ant-eating chat has won.

The aardvark and the ant-eating chat are perfect housemates due to their same preferences.

(birds chirping) The aardwolf also appreciates the burrows of the aardvark.

(birds chirping) Aardwolves look like hyenas.

They are a species of hyena, but they don't eat like hyenas.

Aardwolves are specialized termite eaters.

What they miss, though, are strong paws for digging.

(curious music) ♪ That's why they primarily feed on harvester termites, as the insects leave their mound during daytime.

How convenient.

The aardwolf can usually just slurp them up easily from the ground.

♪ But now, during winter, times are tough.

The harvester termites rarely leave their mounds anymore.

But having the right housemates pays off.

This mound was broken down by an aardvark.

It is now a real all-you-can-eat buffet for the aardwolf, providing a continuous flow of delicious treats.

♪ (sweet music) This excess of food leaves time for other important things.

A female aardwolf is approaching.

♪ The two find each other.

(mellow music) ♪ Mating in typical aardwolf manner.

This can take up to six hours!

♪ Pretty exhausting.

(birds chirping) The nutritious termites are an ideal snack to replenish one's strength.

(birds chirping) And so, the aardwolf doesn't leave the termite fountain until late at night.

(calm music) ♪ Aardwolves have a very efficient tongue.

Each second, they swallow hundreds of termites.

During a single night, this can add up to 300,000.

♪ (yipping) ♪ An all-you-can-eat buffet served by the aardvark, and free housing.

This aardwolf could have it worse.

♪ (energetic music) ♪ At the termite mound, a female dwarf mongoose is waiting for the return of her troop.

She was ordered to babysit.

The biological mother does not care for her offspring.

She leaves this task to the subordinate females.

♪ As usual, the termites are busy repairing the damages to their home.

(termites scuttling) ♪ The babysitter, too, has a lot to do.

She even suckles the young.

♪ (squealing) ♪ (tense music) ♪ An uninvited guest has arrived, a rock monitor.

It is searching for food, and the termite mound is a real gold mine.

♪ (squealing) ♪ (animal cooing) The rock monitor wants to get inside.

It's looking for the fortress's weak point.

(rock sliding) The powerful front legs and sharp claws are used to make a way in.

(digging) But the rock monitor doesn't get far.

(birds and insects chirping) There must be another way.

(birds and insects chirping) Its forked tongue guides the way.

It can indicate a smell's direction.

(animal cooing) Made it!

(ominous music) ♪ Inside the termite flat share, the roommates are trying to hide.

♪ The termites living in the basement don't even notice the attack.

♪ An egg-eating snake has found a cozy apartment upstairs in the flat share to spend the winter.

♪ The rock monitor enters the snake's home without permission.

(hissing) ♪ As they only feed on eggs, these snakes lack both teeth and venom, but they still know how to defend themselves when being provoked.

(hissing) This one fiercely strikes and makes hissing noises by rubbing its scales together.

The defense is proving effective.

♪ The rock monitor is still hungry.

♪ The benefits of a fully air-conditioned termite mound also attract other reptiles.

Some even breed in here.

This clutch of snake eggs is just what the rock monitor has been looking for.

♪ And so, the snake's brood chamber turns into a pantry.

Most of the time, reptile eggs remain undetected.

The termite mounds offer perfect growth conditions.

Air humidity remains constant, it is warm, and termites have no interest in the eggs.

♪ Snake eggs stick together naturally so that they do not roll around.

Any movement may affect the embryos.

Moreover, it's harder for predators to snatch single eggs when they form a clump.

♪ Finally, the raider is leaving... (birds chirping) ♪ ...unnoticed by the house owners.

(scuttling) (bright music) ♪ (birds chirping and wings flapping) ♪ At the weaverbirds' nest, there's always work to do.

It is constantly expanded, the roof is improved, and new apartments are built.

The residence can never be big enough, but the birds are slogging their guts out alone.

No other flatmate is helping... (intriguing music) ...neither does the spotted eagle-owl, even though it got the penthouse with panoramic view.

Up here, it's both comfortable and safe.

♪ Potential enemies can be spotted from afar.

(sinister music) ♪ All clear.

This young leopard wasn't after the owl.

At night, the eagle-owl sets off for a mouse hunt.

(curious music) Now it becomes obvious why the bird was sitting up here in the first place.

It's nesting on the roof of the weavers' colony.

♪ One of the young already felt confident enough to sit on an outer branch.

♪ To compensate for rent for the prime location, eagle-owls keep away other raptors and small mammals that could harm the sociable weavers and their offspring.

(hooting) But who would dare to come too close to this shared flat when there are so many attentive flatmates?

(bird cawing) (playful music) ♪ The pied barbet, just like woodpeckers, usually lives in wooden houses, but this one is considering moving into a more comfortable apartment in the weavers' residence.

♪ No one seems to notice it, neither the pygmy falcon, nor the eagle-owl.

♪ The pied barbet just jumps right into a flat whose owners have gone out.

(lively music) ♪ The weavers must take care of the matter all by themselves.

They do it their way, non-violent, but with a lot of clamor.

♪ The pied barbet has had enough.

It returns to its wooden cabin.

(intriguing music) The night guard has returned to its post.

On its back, there's another flatmate who just wanted to stop by.

♪ Paper wasps are nesting at the bottom of the weavers' nest.

They feed their young with mashed-up caterpillars.

♪ Whoever comes too close to their nest is painfully stung.

In this way, uninvited guests are kept away from the whole weaver colony.

(birds and insects chirping) ♪ It may sound surprising, but despite the chirping and fluttering, the wasps do not attack neither the weavers nor the other flatmates... (birds chirping) ...but they do attack voracious giraffes.

For these giants, a weaver's nest is nothing but a delicious bale of straw, but they know of the painful stings, and so they avoid coming too close to the weavers' flat share.

(insects and birds chirping) (calm music) Down here, in the aardvark's shared flat, things are more tranquil.

♪ The blow flies at the entrance indicate the homeowner is still there.

The blow flies don't leave until the aardvark does.

They spend the whole day sitting on the ceiling doing things that flies do, cleaning themselves and looking for partner.

(lighthearted music) ♪ The flies wait until the landlord wakes up.

Then, they have to move fast.

Whenever the aardvark leaves the shared flat, the flies jump on its back and cling to it.

They're attached to the cave's host, but not completely out of selflessness.

♪ (flies buzzing) ♪ (scratching) ♪ (urinating) As soon as the aardvark has finished relieving itself, dinnertime starts for the flies.

A short flight, and they've landed on the waste.

Once the aardvark sets off, the flies quickly return to its back.

♪ In this way, the lazy flies enjoy an all-inclusive cruise into the sunset and towards the next burrow.

(peaceful music) ♪ (crickets chirping) The young aardvark has woken up without its mother.

She left.

From now on, it has to get by alone.

(calm music) ♪ It sets off determinately.

The aardvark will now build its first own underground apartment and start a new flat share.

When it comes to the location, it's not picky.

The only thing is that the soil must not be too soft because this could risk a collapse of the apartment.

♪ But one burrow is not enough, there must be one to find food, another one to hide from predators, one to nap, and one to live in.

And so, the aardvark continues digging burrows as deep as six meters below the ground.

♪ No effort is too big.

The claws of the young are already powerful enough to fulfill the task.

(digging) ♪ Done!

The first burrow is finished.

There are only several hundreds to go.

New flat shares will be created here, but the young aardvark will barely get to see its flatmates.

They have their own daily routine.

♪ (energetic music) ♪ Dwarf mongooses are very social and spend most of their time in their apartment.

♪ (squealing) ♪ (insect buzzing) ♪ Again, the termites must clean up after them.

(insects scuttling) ♪ (playful music) Finally, the annoying flatmates are leaving.

Dwarf mongooses change the shared flats that they live in regularly.

They rotate between 10 to 30 different termite mounds.

As usual, they don't exactly behave well in their flatmates' homes.

They even leave their waste in front of the entrance!

At the other termite mounds, the same mess is found.

Who is supposed to clean up all of this?

♪ Maybe the cockroach?

No, it's impossible for the small insect to finish all of it... ♪ ...but it sure can grab a bite.

♪ (scurrying) (curious music) In the termite flat share, there's another flatmate, though... ♪ ...the Sudan plated lizard.

♪ The mongoose and the lizard not only live together in the termite mound, they also get along fantastically!

♪ The Sudan plated lizard could eat the mongoose, or the other way 'round.

The mongoose could eat the lizard, but they don't.

The mongoose only eats insects and other small animals, and the lizard has found a much more sustainable way to get food.

♪ Whenever the mongoose leaves a dirty mess, the Sudan plated lizard doesn't complain.

♪ Quite the opposite.

If the mongoose's waste is fresh enough, the lizard is happy to clean it up.

♪ And so, everyone gets their share.

Thanks to the poor digestion of the mongoose, the Sudan plated lizard had a nutritious meal, and the termites, a clean entrance area in front of their home.

(bright music) ♪ The giant nests of the weavers are quite impressive, but their builders are miserable structural engineers.

(birds chattering) ♪ A woodpecker's hole in the supporting purlin is not exactly convenient.

But why should the woodpecker care about it?

The extremely heavy nest is none of its business.

The bird is busy enjoying the view.

The weavers keep building and building.

Their nest is incredibly heavy now.

If the branch breaks, the nest dwellers will become homeless in one swoop.

(creaking) (wings flapping) (cracking) (tense music) ♪ (thudding) ♪ (somber music) ♪ The weaverbirds and their flatmates have been lucky.

No one was hurt.

But the birds must build a new home now.

The old one on the ground no longer offers protection.

It is now nothing more than building material for others.

♪ (birds chirping) ♪ For now, there are just a few branches on a tree.

But soon, there will be something big.

Still, it will take a long time until these branches have grown into a home for many different housemates.

♪ (captivating music) The burrow of this young aardvark will soon also provide a residence to many other animals.

Some will leave the place at night.

Others will move in.

They will hardly ever meet each other.

But in this way, the most is made of the living space.

With the help of all, the burrow will be expanded and side passages will be built to the benefit of all.

♪ With termites, it's different.

They seems to have the worst flatmates.

Some of them regularly destroy the mounds, and others consider them as food.

Reptiles occupy their air-conditioned living space with their offspring.

The termites have no choice but to isolate themselves.

And their flatmates?

They are living their best life.

♪ Despite their impressive tree houses, weaverbirds live in constant danger.

(hissing) Lucky for them, they have so many flatmates.

While some protect them, others keep the residence neat and tidy.

Everyone fulfills their household chores.

No doubt, living together has advantages and disadvantages, but the animal communities of the Savannah don't necessarily differ from human communities.

It's for the benefit of all if there's more space to live, more food, more encounters, and more diversity.

♪ (insects chirping) ♪ (bright music)