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AnimalsTranscript
00:0666 million years ago, an asteroid was on a direct collision course with the Earth.
00:15Its impact was to dramatically change the course of life on our planet.
00:25Leading to a mass extinction that wiped out three quarters of all animal life.
00:35Out of the darkness that followed, emerged a group that went on to dominate the world.
00:43That group is the mammals. Highly adaptable and remarkably widespread.
00:49They are now found in every ocean and on every continent, in the air and underground.
00:55In this series, we will reveal the secrets behind their success
00:59and the challenges they now face in a world dominated by the most successful mammal of all, us.
01:43Evening in the forests of Central Africa.
01:46Evening in the forests of Central Africa.
01:59A family of chimpanzees is looking for somewhere to spend the night.
02:14Like us, they have excellent daytime vision.
02:19But at night, they could be caught unawares.
02:24As the light fades, they climb up into the canopy, where it's safer.
02:42There, they start to make beds for themselves.
02:52Here in the treetops, the whole family will be able to sleep soundly through the darkest hours.
03:03But sleeping at night is unusual among mammals.
03:13More than two thirds of them only become active after the sun has set.
03:20So, while you and I and chimpanzees are fast asleep, most mammals the world over are as active as they
03:30will ever be.
03:44Zambia.
03:47It's evening and the light is fading.
03:57A female leopard is starting to think about hunting.
04:13She can see there is plenty of possible prey.
04:24But in daylight, they can see her just as easily as she can see them.
04:39That, however, is all about to change.
04:45When her remarkable night vision will give her a crucial advantage.
05:02The leopard's eyes have a reflective structure behind the retina called a tapetum.
05:09That amplifies even the tiniest amount of light.
05:17That now becomes very valuable because tonight it is particularly dark.
05:29Impala have learnt to be wary.
05:43With her prey so alert, she has little chance of catching one here.
05:55But there are other opportunities nearby.
05:59But there are other opportunities nearby.
06:17Many people who have seen them on the beach.
06:1820 metres above the forest floor, a troop of yellow baboons are settling down for the night.
06:32Even on such a dark night as this, a leopard can pick out the most vulnerable.
06:39Wolf.
07:10Baboons have poor night vision.
07:24Their hearing, though, is excellent.
07:32The closer she gets, the greater the risk of waking them.
07:54It's the only way they can do it.
07:55The troupe is now fully alarmed,
08:00so that she becomes bolder.
08:30If you don't know why they won't be even up to us.
08:32In all the commotion, a mother and baby take a wrong turn.
08:43And now they are trapped at the end of a branch.
09:01There seems to be no escape.
09:23The thinnest of branches offers the mother and baby a lifeline.
09:39With the baboon so alarmed, she will need all her power and agility now.
09:50The troop scatters again, and one makes a fatal mistake.
10:14Many nocturnal mammals, like the leopard, have extremely sensitive night vision.
10:25But how do you find your prey if it is completely out of sight?
10:38The Sahara.
10:42Under a moonlit sky, it's one of the quietest places on Earth.
10:53In the cool air of night, sound travels further than it does in the heat of the day.
11:03And one mammal uses that to its advantage.
11:13It's a creature that's rarely seen.
11:20Because it can hear us coming.
11:28A fennec fox.
11:32Its body is scarcely bigger than that of a guinea pig.
11:36But those ears are huge.
11:39If anyone can hear a pin drop, a fennec fox can.
11:45And in this vast open space, it's listening for the tiny footsteps of its prey.
11:56A gerbil.
12:08But at the first sign of danger, gerbils hide underground.
12:20The fox searches dune after dune,
12:27listening for the faintest of audible clues.
12:34Those enormous ears are so sensitive,
12:37they can even hear the movements of prey hiding underground.
12:47But then, they have to be dug out.
13:01There is no gerbil.
13:04But those ears help pinpoint all sorts of other smaller creatures under the sand.
13:13Such as beetles.
13:16And lizards.
13:20And they don't only help to find food.
13:28This fox can hear a distant call echoing across the dunes.
13:40...
13:51That's what she is looking for.
13:52It's January.
13:54The beginning of the breeding season.
13:58.
14:11But for this pair, perhaps it's just a little too early.
14:30To meet the challenges brought by darkness, nocturnal mammals have sharpened their senses in extraordinary ways.
14:40And that's all been possible because mammals started their journeys into night a very long time ago.
15:08200 million years ago, the land was dominated by dinosaurs and other great reptilian hunters.
15:16But they were mostly active during the warmth of the day.
15:22So the early mammals kept out of their way by only emerging to feed at night.
15:32They were very small. They had hairy coats which kept them warm.
15:39And they found their way around by using one of the most ancient senses of all. Touch.
15:51In fact, they were probably very like this little creature, a tiny Etruscan shrew.
16:01This one is a mother.
16:06And she's taking her young family for their first nighttime walk.
16:14To ensure they don't get lost in the darkness, they literally keep in touch.
16:27The babies hold on tight until they reach the safety of a new nest.
16:39Touch not only helps them find their way, they use it when hunting.
16:50Weighing less than a ping-pong ball,
16:53Etruscan shrews are the world's smallest terrestrial mammal.
17:00But they're still formidable predators.
17:14Some of the hairs on the end of their noses have become enlarged into whiskers that are especially sensitive to
17:21touch.
17:25Like an extra pair of hands, they guide them on a never-ending search for a meal.
17:48To fuel their frenetic lifestyle, they feed every few hours.
17:55A bush cricket.
17:58It's almost as big as she is.
18:02And well able to make a quick getaway.
18:09She will need the lightest of touches if she's to catch it.
18:18So she switches to whisker mode.
18:26To prevent it escaping, she must grab one of its jumping legs.
18:44She won't get a second chance.
18:57She won't get a second chance.
19:02It's a relatively enormous meal.
19:06But she must eat a lot to feed her ever-growing family.
19:11And fuel her fast-paced lifestyle.
19:16So she'll soon be out hunting again.
19:27Feeling their way by touch is not the only method by which mammals deal with the problems of darkness.
19:38In Argentina, as night falls, life starts to stir in an abandoned farm building.
19:51There are all kinds of smells drifting through the air.
19:55Some powerful.
19:58Some faint.
20:01Some faint.
20:02And one nocturnal mammal has an extraordinarily sensitive way of detecting even the faintest of them.
20:15An armadillo.
20:18There are 21 species in the Americas.
20:23This one is the large, hairy armadillo.
20:38After dark, he heads out into the surrounding pasture.
20:47Guided by a highly sensitive nose.
21:02This male has detected a smell that he finds especially enticing.
21:14And soon locates the source.
21:19A female in season.
21:22And she's producing an irresistible perfume.
21:30He's fallen for her.
21:36But she is not so sure about him.
21:43So she takes the lead.
21:49The male has to keep up as best he can.
21:57Back in the abandoned building, the clutter in the rooms makes things more difficult.
22:10He's lost her.
22:14But her scent is everywhere.
22:20He's not giving up.
22:45Eventually, she leads him to a quiet corner.
22:49Eventually, she leads him to a quiet corner.
22:57Her choice is made.
23:07Equipped with an array of sharp super senses,
23:11nocturnal mammals have little difficulty in finding not only food,
23:16but mates.
23:20But some of the most successful of all don't only use their own senses.
23:27They also rely on each other.
23:41The N'Goro N'Goro Crater in northern Tanzania.
23:48One of the greatest mammal hotspots in the world.
23:53So they are today's novel.
24:21Any constellation's evangelist and her chargers will tonight?
24:22And they are caught up as much undocally.
24:22the crater attracts great numbers of predators, amongst them spotted hyenas.
24:37And this female is a member of one of the most exceptional and caring families.
24:58She will nurture her cubs for 18 months.
25:08And she is not a single parent, far from it.
25:16She has the support of a sisterhood.
25:20A clan ruled by females, 60 adults strong.
25:35With so many mouths to feed, hyenas must hunt almost every night.
25:54As dusk falls, they head out, splitting up into small groups, to widen their search for prey.
26:26They are well equipped to hunt in darkness, with excellent low-light vision.
26:33A superb sense of smell, and highly acute hearing.
26:40But they aren't the only ones out hunting.
26:48The pride of lions has already made a kill.
27:07The hyenas tried their luck at scavenging.
27:22The believians who are not hunting,
27:23the lithium-ion and the coastal местopoulos with young knights.
27:23year's old, they have to be a car and the rescue.
27:28They are the ones that might be young for the first time.
27:33They are the ones that might be young for the first time.
27:33They are the ones who are the ones who are the ones that might not find.
27:33For example, they are the ones that are huntland.
27:34What is that?
27:36The thieves can appear.
27:47There is no easy meal to be had here.
27:54But not far away, they find one of the most impressive mammals in the crater.
28:02One with the reputation of being particularly dangerous.
28:15A single one of them would be enough food for the whole hyena clam.
28:20But a full grown buffalo weighs three quarters of a ton and is very formidable.
28:30The small group of hyenas look for a weakness in the buffalo's defense.
28:47It's just too risky.
28:57But when the odds are stacked against them, hyenas play their trump card.
29:09They summon reinforcements.
29:15Their calls echo across the crater.
29:28Clan members up to three miles away hear their cry for assistance.
29:54The buffalo is still standing strong.
30:02More reinforcements are needed.
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30:32Now, with the combined strength of the whole clan,
30:36they have a chance.
30:40But a wounded buffalo is particularly dangerous.
30:47One stab from those horns could kill.
31:07They must force the buffalo off its feet.
31:34There's no escape from so many hyena.
31:53Their ability to work as a team makes the spotted hyena one of Africa's most successful predators.
32:08But there is one mammal that has brought working together to a whole new level.
32:21Nearly a meter beneath the surface of the Kalahari Desert.
32:27There are tunnels.
32:31Where normally animals live in permanent darkness.
32:35Only our lights make them visible.
32:45Tomorrowland mole rats.
32:55The heart of their colony is their nesting chamber.
33:06And here, amongst the massive bodies, lies the queen.
33:18She is the only female who breeds.
33:22All the rest, whether male or female, are workers.
33:34Their main task is to dig for food.
33:45But the dry season brings a challenge.
33:50The soil becomes so hard and dry
33:53that mole rats are unable to dig out the tubers on which they feed.
34:06And their larder is nearly empty.
34:15Digging is now so difficult,
34:18they have to save their energies until conditions improve.
34:36It's late November.
34:38The rains, at last, have returned.
34:46Each downpour helps to soften the soil.
34:54And the workers can start digging again.
34:59Now, using their huge incisors,
35:02they are able to cut through the rain-soaked soil.
35:10The first tubers they find, they eat on the spot.
35:18Once they've had their fill,
35:20they carry away the tubers they find
35:23to a chamber that serves as a larder.
35:29The colony works without pause.
35:34After the rains, they may dig half a mile of new tunnels.
35:40Shifting nearly three tons of soil.
35:51All in order to restock their larder.
36:02Finally, they have accumulated enough food
36:05to see them through the next dry season.
36:13Thanks to their dedicated teams of workers,
36:17no rats have succeeded in an underground world
36:21in permanent darkness.
36:29But there is one group of mammals
36:31that has colonized the dark with such success
36:34that they've spread to almost every land on Earth
36:37outside the polar regions.
36:41Dusk, on the northwest coast of Trinidad.
36:54Deep inside a sea cave,
36:57a colony of greater bulldog bats are waking up.
37:13their English name is a libel or a complement
37:17is perhaps debatable.
37:22Bats are the only mammals that have true powered flight.
37:30Getting airborne requires a thorough pre-flight check.
37:40Their wings are membranes of skin stretched between greatly elongated fingers.
37:49Licking helps keep them supple.
37:56These particular bats are also equipped with an unusual feature.
38:03Their feet have enormously elongated hook-like claws.
38:13They're certainly useful for back scratching.
38:22And ear-picking.
38:28But most importantly of all, they are for hunting.
38:39Inside their cave, it's pitch black.
38:43But these bats have a sixth sense that enables them, in effect, to see in the dark.
38:56Echo location.
39:02They make a series of very loud, short calls.
39:07And by listening to the echoes, are able to create a mental map of their surroundings.
39:20It's so detailed that they can navigate in total darkness.
39:30And bulldog bats use this talent to catch fish.
39:37Which is not easy.
39:49Their calls bounce off the surface of water.
39:53So they can't reveal anything beneath.
39:56But they can, nonetheless, give clues.
40:08A bat will scan the surface of the water with broad echolocation calls.
40:17When something is detected, they're able to focus on it.
40:25A fin cutting the surface is enough to make them start fishing.
40:34But catching one requires precision flying.
40:51Using its feet like grappling hooks, it wakes the surface of the sea.
41:01And this is, literally, a shot in the dark.
41:10The bat's timing has to be exactly right to coincide with the fish breaking the surface.
41:29Eventually, repetition brings a reward.
41:43Thanks to this super sense, these remarkable bats have become astonishingly successful
41:50fishermen.
42:18Bats were almost certainly flying in the night sky.
42:21when the dinosaurs became extinct and now nearly one-quarter of all mammal
42:29species are bats and that is not all
42:40they also form the most numerous gatherings made by any mammal
42:50Austin in Texas
42:57every evening in early August crowds gather around Congress Avenue Bridge
43:06waiting for one of the city's great spectacles
43:11as the sun sets
43:13the stars appear
43:26Mexican free-tailed bats
43:32the gaps on the underside of the bridge
43:35provide excellent roosts for the bats
43:45and now one and a half million of them live there
43:49the forest
43:52and now one and a half million of them live there
44:19and now one and two and a half million of them live there
44:24These free-tailed bats live very successfully right alongside us.
44:31There are now more bats than people in Austin, and their numbers are still increasing.
45:12Mammals have evolved many ways to deal with the problems of living in the dark.
45:21But none have done so more successfully than bats.
45:28In recent years, however, other mammals have started to alter their habits, and are changing
45:39from being active in the day to coming out at night, and they're doing so in order to avoid
46:03us.
46:05The coyote.
46:08A species of dog as wild and untamed as any wolf or jackal.
46:15And this animal that was once mostly active in the day has started to take the night shift.
46:25Under the cover of darkness, they're now living right in the heart of America's biggest cities.
46:41This is Chicago, home to over nine million people.
46:53For an animal to be successful here, it helps to be active when we are not.
47:07Just as early mammals became nocturnal in order to avoid daytime dinosaurs, these coyotes are
47:15now doing so in order to avoid us.
47:24And as a consequence, they're thriving.
47:30Greater Chicago is now home to over 4,000 coyotes.
47:41They keep a low profile where they can, though Chicago, like any city, is full of dangers.
47:54But these clever coyotes are now streetwise.
48:01Some have even learnt when it's safe to cross the road.
48:17The reason for these urban journeys?
48:21Chicago's downtown parks.
48:27Little oases of wilderness that attract a surprising variety of other wildlife in considerable numbers.
48:43The coyotes don't live on trash.
48:57They are skillful hunters.
49:00They are skillful hunters.
49:16Before dawn arrives, these wily coyotes retreat into the shadows.
49:28It's the adaptability and ingenuity of these mammals, indeed of all nocturnal mammals, that has enabled
49:36them to become active in conditions that we avoid.
49:42They have mastered the dark and found the richest rewards.
49:48And it should really be no surprise.
49:51After all, they've been doing just that for millions of years.
50:15One of the greatest challenges facing the dark team was filming fennec foxes.
50:21They travelled to Tunisia and into the Sahara.
50:26Helping them was Italian wildlife photographer Bruno Damicis.
50:31Having worked here before, he knew just how difficult this would be.
50:36We don't know much about fennec foxes.
50:38We don't know much about fennec foxes.
50:38The studies done on these species in the wild can be counted on one single hand.
50:44You have this animal living in the largest desert of all, moving mostly at night.
50:49So, yeah, it is, it is super challenging.
50:52It is very difficult.
50:54Beshir Belhaj, a local fennec expert, was key to helping them track down the best place to film.
51:00Ah, Bruno, ah, Bruno, Bruno.
51:03Oh, press the fennec.
51:06Yeah, that's great.
51:08Thank goodness they're here.
51:10Oh, here, you see, you see.
51:13You look at fennec scats.
51:14It's like beetle casings.
51:17Yeah, many beetle casings.
51:19The signs were encouraging.
51:21But producer Stuart Armstrong knew that the challenge was still immense.
51:27Great that we found tracks and signs of fennecs.
51:29But it's rolling dunes.
51:32You know, something will disappear so quickly behind a dune.
51:36And then you add in the challenge of doing it in the dark.
51:40Early next morning, Bruno and Stuart got to work setting up numerous camera traps.
51:47Using super sensitive low light cameras would give them the best chance.
51:51With new technologies, we can get beautiful gleams of what goes on at night directly with the moonlight.
51:59So it is super exciting.
52:01And wildlife cameraman Pete Kalis and Marco Andrini started their night shifts.
52:07At least we know that there are foxes around.
52:10My wish is to see one in front of us.
52:28With clear skies and a full moon, filming conditions are excellent.
52:34But being nocturnal, extremely shy and living in such remote locations, fennec foxes have been filmed only rarely.
52:44But after only a few nights, this ghost of the desert revealed itself.
52:49Oh wow.
52:56I actually can't believe it.
53:05And when they checked the camera traps, the news got even better.
53:09Yay!
53:13Look at that!
53:15No way.
53:15Look at the size of those ears.
53:17Yeah.
53:18That's huge.
53:19Yeah.
53:21Sweet little thing.
53:23That's so encouraging.
53:25That's super encouraging.
53:29All was going well.
53:32But their good luck soon vanished.
53:38The foxes had disappeared.
53:42Night after night brought no rewards for camera operators or camera traps.
53:49Keep trying.
53:50That's the only thing I can do.
53:51I really hope they will come.
53:58Nothing.
54:04Nothing.
54:05Nothing.
54:05Nothing.
54:08Frustrating, to say the least.
54:15The crew eventually discovered the reason for the foxes' sudden disappearance.
54:21A few miles away, they found a recently abandoned camp.
54:26And amongst the litter was the most shocking find.
54:33We're all a bit stunned.
54:35We discovered one of the foxes on the floor and we thought that was shocking enough.
54:40And then just, just up here, there's a second fox.
54:50It's just heartbreaking.
54:57No end to this horror.
55:00Here, it is illegal to kill a fennec fox.
55:04But it's difficult to police such a remote place.
55:07And, sadly, they're still heavily persecuted.
55:11Trapped for pets, but also for food, fur, and in this case, more shockingly, it seemed for fun.
55:21I'm all broken.
55:22I'm all broken.
55:24I'm all broken.
55:30Saharan wildlife is some of the most threatened on earth.
55:35And only with local champions can the situation here change.
55:40As a young man, Bashir used to trap foxes, but he hunts no more.
55:46He's become an advocate, helping to spread the message throughout the local communities that fennecs need protecting.
55:54And he hopes a film about these foxes could help with that.
55:59Which made him and the crew even more determined to not give up.
56:09Bashir knew of another potential location.
56:12A remote oasis.
56:13And the signs are encouraging for everyone.
56:18Wow.
56:19There are loads of tracks.
56:21There must be more than one animal.
56:22This cannot be one animal.
56:24This is very exciting, isn't it?
56:26Yeah.
56:27New location.
56:28A new day.
56:30New hope.
56:34But would the tracks and signs turn into success for Marco and Pete?
56:42How are you doing?
56:43How was your night?
56:44It was a long, long, long, long night.
56:48It must have been crazy when I choose this height.
56:55It's too small.
57:01But it worked.
57:04There was one fluffy, then two fennec foxes there.
57:14To see two foxes, possibly a courting pair, brought the team a lot of hope.
57:21These animals are so incredible.
57:24It's like the spirit of this desert.
57:29It was so beautiful.
57:31I'm so happy.
57:32Now.
57:36In remote corners and against many odds,
57:40these endearing foxes still survive.
57:44And hopefully, the support of local communities
57:48will help to conserve not just fennecs,
57:51but other threatened wildlife across the Sahara.
58:04Next time,
58:06mammals continue their journey into our world.
58:13A world changing faster than ever before.
58:20And full of new challenges.
58:33From zooquests to dynasties, the Sir David Attenborough collection on iPlayer celebrates decades of pioneering work.
58:40Press red to watch now.
58:42Here next,
58:43Cordiff plays host to a new Antiques Roachal.
58:47The
58:47on the screen.
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