The Most Unique Creatures of our Hidden Forests | BBC Earth

0:00 and it is one of the poison dart frogs.

0:03 This is a walking billboard of a frog.

0:06 What it's advertising is its own toxicity.

0:09 These animals contain some pretty potent

0:11 chemicals in their skins known as alkaloids.

0:14 And uh by walking about on the forest floor,

0:16 this is what is known as a textbook case of aposmatic coloration,

0:20 which basically says, "Don't eat me.

0:22 Don't even put me anywhere near your mouth or your eyes because I

0:25 could ruin your day." I'm very very pleased to have found this one.

0:28 But there is one more I want to get

0:29 hold of that lives in the forest around here.

0:31 And believe me, it's even smaller.

0:48 Oh, there's one.

0:49 There's one.

0:49 There's one.

0:51 Right.

0:51 These are so tricky to catch.

0:54 Right.

0:54 This is the This is the This is the little frog.

0:57 This is the strawberry poison dart frog.

1:00 Got it.

1:01 Haha.

1:02 You thought I'd done this before, wouldn't you?

1:04 This is the poison dart frog known as the strawberry poison dart frog.

1:07 And you can see why it has that strawberry reference in its name.

1:12 Just look at that scarlet or orange um top to his body.

1:17 This again is another example of warning coloration.

1:20 This frog also contains those alkoids in its skin.

1:24 And um I know people who have actually um well

1:28 licked their fingers after holding one of these and um they've

1:30 gone through very unpleasant um sensation of actually having or feeling

1:34 like they've actually got a golf ball in their throat.

1:36 They have real trouble breathing or swallowing.

1:38 But uh very just so potent yet uh so seemingly harmless to look

1:44 at and all from a frog you can fit on your thumbnail.

2:17 ants.

2:18 Leaf cutter ants to be precise.

2:19 Now you might think of these insects as being the sort of things that terrorize

2:23 and rage your picnic or put the kaosh

2:25 on amorous activities that occur on the lawn.

2:27 But not these guys.

2:28 Sure, they can defend their own if you go poking around in the nest,

2:31 but these are kind of like the I know the the peaceful ants.

2:34 These are the the harvesters and the gatherers.

2:36 And what we've got here is a foraging trail of ants

2:40 carrying little bits of leaves back down to their nest.

2:49 These ants actually have little crafty predators,

2:52 parasitic flies and wasps that will quite happily come

2:55 along and lay their eggs on the ant's head.

2:58 Now, it's thought that the little tiny guard ants that these ants carry

3:01 on their leaves are kind of the special forces of the ant world,

3:04 defending against aerial attack from these bulb predators.

3:15 Deep down underground, the ants are taking these leaves down to a special

3:18 fungus garden because it's the fungus the ants depend on.

3:22 Without it, they're stuffed.

3:23 They simply cannot digest the juices and the plant

3:26 material they bring down into the nest.

3:33 Now, this bizarre carnival of ants are actually

3:37 vitally important to the running of the forest.

3:39 What they're doing is recycling nutrients,

3:41 bringing down vegetable matter from the canopy

3:44 level and putting it back into the ground.

3:47 And it's thought they're so important in the rainforest,

3:49 they actually consume 10% of all living plant material.

4:06 Now, one of the continual frustrations of rainforests

4:09 is it is a hugely three-dimensional habitat.

4:11 There's an awful lot lot more up there than there is down here.

4:14 And being a two-dimensional groundbased monkey, I'm in trouble.

4:18 Um, unlike these guys,

4:21 the first sign you get of a group of white-faced cappuccin monkeys

4:26 moving through is branches falling

4:28 to the ground and leaves and occasional twitterings.

4:31 But, uh, they have just moved through, or they're moving through as we speak.

4:34 There's still some around.

4:40 Now, one of the surprising things going on here,

4:42 which I didn't know, it's a brand new thing for me,

4:45 is that uh every now and then through the leaves, you see a bird of prey.

4:48 Um it I I've got no idea what these are,

4:51 but what they're doing, they seem to be chaperoning the monkeys.

4:54 Not as you might expect, pick off an unwary monkey or two.

4:57 Um but actually to pick off the insects because as you might notice,

5:00 these capacins are far from um ballet dancers up there in the canopy.

5:05 They lack finesse and they're constantly shaking the branches

5:08 about and there's bugs and insects and stuff being dislodged.

5:11 And that is what the birds of prey are picking up on.

5:14 Yet another example of one of those beautiful

5:16 relationships between different species here in the rainforest.

5:19 Island, 2 and 12 km of rock protruding from the ocean.

5:25 It's home to a living fossil, a relic barely changed for over 100 million years.

5:37 the Chitara and half the world's population survive on this one island refuge.

5:47 During the reign of the dinosaurs,

5:49 the ancestors of the Chittara were everywhere.

5:54 They survived the cataclysm that killed off [music] the dinosaurs,

5:57 but then couldn't compete with the mammals and died out

6:02 everywhere except on what was then a mammal-free New Zealand.

6:14 Unlike mammals, touittara live life in the slow lane.

6:22 Days can pass when they barely move a muscle.

6:32 Sometimes taking just one breath an hour.

6:43 [bell] They feed on wetters, beetles and other invertebrates.

6:52 but don't appear very good at catching them.

7:00 Even after millions of years of practice,

7:02 eye mouth coordination is not what it could be.

7:10 Survival of the fittest just doesn't seem to apply here.

7:21 The Chuittara's survival, first on New Zealand,

7:24 now on Steven's Island, proves a point.

7:28 Islands are pretty safe places to be, at least until invaded.

7:36 Fortunately [music] for the Stevens Island Chuittara,

7:38 it did survive a brief mammal invasion.

7:42 But for some of the other wildlife here,

7:44 [music] the invasion was rather more catastrophic.

7:50 New Guinea is a [music] vast island nestled

7:53 close to the continental land mass of Australia.

7:57 As we move south and east to smaller,

7:59 [music] more distant islands, the wildlife becomes even more unusual.

8:05 The little known island of New Calonia is a small sliver

8:09 of Australia that was cast a drift over 60 million years ago.

8:20 It's home to a creature that seems to have evolved quite strangely.

8:29 It has wings, but it can't fly.

8:41 It is the Kagu.

8:51 [laughter] Kagu families stick together with young

9:07 from previous years helping to declare the family territory.

9:16 All intruders are chased away.

9:31 It's the breeding season when males

9:34 rekindle the flame with their lifelong partners.

9:40 [music] [music] [music] It's hard to know [music] what the kagu is related to.

10:10 A heron, a rail, or maybe a pigeon.

10:15 Its closest relative may actually be the sunbitten [music] of South America,

10:20 11,000 km to the east.

10:26 [music] [music] [music] She may not seem too impressed,

10:46 but then kagus always keep their feet very firmly on the ground.

10:52 Autumn is approaching and a male Darwin's beetle is looking for a partner.

10:58 His success will be down to the size of his jaws and how he uses them.

11:14 [music] He heads off to the forest to start his search.

11:20 The females will be in the trees, probably feeding somewhere on the trunk.

11:25 They should be easy enough to find.

11:33 But when the trees are more than 25 m tall, it's a long way to climb.

11:43 [music] There she is.

11:49 [music] Unfortunately [music] for him,

11:57 all the other males in the neighborhood are also after her.

12:01 He has no choice but to fight them off.

12:09 But it's [music] not just about strength.

12:11 It's about grappling.

12:21 He reaches over the rival's head and hooks

12:24 his enormous jaws under his wing covers.

12:37 He gets a grip, lifts, and chucks.

12:52 He climbs onwards.

12:54 There are other males standing in his way, but nothing will stop him now.

13:00 [music] They meet at last.

13:20 [music] She doesn't appear to be totally smitten.

13:36 [music] But she finally allows him to wrap

13:38 his great big jaws around her and they get intimate.

13:48 [music] but then he throws her out of the tree.

14:07 Beetle armor is tough and luckily she's just where she [music] needs

14:11 to be to lay her eggs on the forest floor among the roots.

14:24 Nightfall brought Wallace some restbite.

14:26 After each strenuous day,

14:28 he was in bed by 8 just as the dark jungle [music] came alive.

14:39 At one camp, villagers brought Wallace a nocturnal creature

14:42 that seemed to defy another key rule of Victorian science.

14:46 That God designed animals perfectly.

14:50 And if we're lucky, I can find it.

14:52 I'm looking for Wallace's flying frog.

14:55 And it's not easy because it spends most

14:57 of its time up there in the jungle canopy.

14:59 But the only time it comes down to ground

15:01 level is at night to mate in a little pond.

15:05 Well, I found a pond over here.

15:06 By the sound of it, there's a lot of frog action going on.

15:10 So, I'm going to investigate now.

15:21 You're cute, but you're not Wallace's frog.

15:29 He's Look at that.

15:30 Whoa.

15:31 Look at that.

15:37 This isn't a Wallace.

15:43 Oh, he's got these wonderful gollum like sticky pads on his toes.

15:51 And you go.

15:58 But what's that?

15:59 Look under here.

16:02 I think I got one.

16:05 Look at that.

16:08 This is Wallace's flying frog.

16:10 It's the most amazing creature.

16:13 Look at it.

16:14 And when it was discovered,

16:15 this was the first time anyone had found anything so fantastical and strange.

16:19 an extraordinary creature.

16:21 His discovery was like science fiction.

16:24 A whole new concept of what a frog could be and it has these huge webbed feet.

16:31 You can see that there.

16:34 Look at that.

16:37 Which allow it to actually glide through the forest.

16:45 All right, we can do [music] this.

16:48 That's where you're headed.

16:48 There's a leaf.

16:51 Okay, I'm going to let you go.

16:56 Fly.

17:04 Wow.

17:06 Look at that.

17:10 Not bad for something trying to fly with its feet.

17:13 With nightfall, the competition in the jungle intensifies.

17:21 As many of Borneo's 180 species of frog now burst into song,

17:35 all singing for a mate, the bigger frog, the louder the call.

17:56 But this male treehole frog is barely bigger than a fingernail.

18:03 He'll need to do something special if he wants to be heard by a nearby female.

18:11 She may only be meters away, but the chorus from the other frogs is deafening.

18:23 This tiny male, however, has a trick.

18:33 He searches for a tree hole.

18:52 The size and shape of the hole are critical.

19:04 He then does something remarkable.

19:11 It begins with a sound check.

19:19 Too low.

19:21 He changes pitch.

19:27 Too high.

19:33 That's it.

19:52 At this specific frequency, the tree hole resonates,

19:57 amplifying the sound and broadcasting the call more than 50 m across the forest.

20:12 For a female, it's music to her ears.

20:33 With superb directional hearing, she can home in on his calls.

20:54 Finally, the tiny couple meet.

21:01 Hidden from predators,

21:03 the treehole will go on to make an ideal nursery for their tadpoles.

21:09 The best way to find birds of paradise is to search

21:12 for their display tree since they use the same tree every morning.

21:22 How about this one?

21:23 Bugan.

21:24 And my guide Janice says he knows where the tree is.

21:28 That's That's that one there.

21:29 Bugan.

21:30 You sure?

21:30 Yeah.

21:31 Banan.

21:31 But I'm beginning to wonder.

21:33 He might just be winding me up.

21:36 This one.

21:41 Oh, what about this one?

21:46 Well, this isn't going quite as well as I'd hoped,

21:49 but Janice assures me if I return the following day before dawn,

21:53 the bird's rockous calls [music] will guide me in.

22:07 So, it's a very early start.

22:17 Well, it's been a 20-minute trek into the jungle up this muddy path in darkness.

22:21 It's about 6:00 in the morning.

22:23 The forest's really starting to come alive.

22:25 I think the birds are very close.

22:28 So, we're going to check them out.

22:32 And sure enough, the birds make themselves heard.

22:42 [sighs] Ah, what an extraordinary thing.

22:49 It's a real privilege to see these in the wild.

22:51 It's very, very rare to get this opportunity.

22:54 And in fact, since Wallace's time, they've only been spotted a handful of times.

22:59 To see one is just is just a an extraordinary rare privilege.

23:08 All the months of hardship, the trekking, the boat disasters,

23:13 all of that would have just faded away when he saw these birds.

23:20 It's incredible the lengths the males will go to to impress a female.

23:24 It's barely light and the jungle is full of their nasal barks.

23:30 All the males have their own individual call.

23:33 It's like they're trying to outdo each other.

23:41 It's like you've got a quack quack.

23:43 All right.

23:43 I've got a walk.

23:46 Their name, the standard wing, comes from the long white feathers that look

23:51 a bit like military standards or flags.

23:57 For Wallace, seeing these birds of paradise,

24:00 these entirely new birds of paradise,

24:02 must have been an extraordinary culmination of his quest.

24:06 I mean, he came here to see these birds, to collect them.

24:10 But to find an entirely new one,

24:12 unlike any other bird of paradise must have exceeded his wildest expectations.

24:16 And in fact, he writes to his agent Stevens in a state of gibbering excitement.

24:21 I consider this my greatest discovery yet.

24:24 And wonderful golden frog.

24:26 It does have a voice, but it's not loud.

24:37 Individual males set up their territories beside the river

24:41 and then wait for females to turn up.

24:44 And since good positions for the territory are not common,

24:48 they may have to hold them against intruders.

24:53 And here one comes.

24:57 Just in case his call is inaudible, he makes his message clear with a wave.

25:09 And his rival waves back.

25:14 He repeats his message so there's no misunderstanding.

25:28 But rival is not deterred.

25:32 Well, that makes things perfectly clear.

25:39 Another arrives.

25:40 Perhaps at last this is a female.

25:58 [music]

25:58 No, it's another male.

26:00 So, there will have to be a wrestling match.

26:08 That should teach him.

26:11 And his rival signals submission by keeping his head down.

26:29 [music] Now, where are those females?

26:49 And here she is.

26:52 She is pure unblenmished gold and much bigger than he is.

27:03 Initially, this was just a stopover as he ventured east,

27:07 but the creatures on Silouese were so curious and unique,

27:10 he returned a further [music] three times.

27:15 This amazing island is where I pick up his story.

27:23 And with the help of my guide, Bobby,

27:25 I'm searching for a tree dwelling creature that would

27:28 become a key piece of his evolutionary puzzle.

27:38 So, Bobby, how do you find a bare couscous?

27:40 Oh, I can smell.

27:42 You can smell them?

27:42 Yes.

27:42 Yes, I can smell.

27:43 It's a The pee was very stinky.

27:46 The pee?

27:47 Yes.

27:47 Very stinky.

27:48 All right.

27:49 So it's a very strong very smell.

27:51 Very strong.

27:52 Yes.

27:52 All right.

27:53 Okay.

27:54 So we can sniff on out.

28:01 Oh, up here.

28:02 Just Yeah.

28:03 Yeah.

28:03 Yeah.

28:03 You see?

28:05 Oh, yeah.

28:05 Got it.

28:06 You got it.

28:08 Yeah.

28:08 That's the first time I've ever seen one of these creatures, a bear couscous.

28:12 And they are quite extraordinary.

28:14 They're unique.

28:15 You only find them here in Silhouazi.

28:17 I've seen other kinds of cuscus throughout Indonesia,

28:21 but this one is the only one that moves around during the day,

28:24 so it's a lot easier to see.

28:28 His face resembles quite a cross sloth.

28:33 You know, slo's quite benign, almost sort of sleepy looking,

28:39 but these look just like they're angry about something.

28:42 And in fact, these are supposed to be uh active during the day,

28:46 but I mean, that's not really active, is it?

28:48 He scratched his ear once.

28:51 That's really at the low end of active.

28:56 What excited Wallace about this lazy couscous is it's a massupial,

29:02 a relative of Australian mammals like

29:04 kangaroos that carry their young in pouches.

29:09 And these weren't the only Australian creatures on this island.

29:12 He also came across Australian birds like cockatos.

29:18 Wallace was starting to see a pattern.

29:20 From her traumatic start in life, Kim Bang has come a very long way.

29:29 But before Mimi feels completely confident

29:31 about releasing her into a family group,

29:34 she wants to see if Kim Bang can recognize and respond to danger.

29:41 So, we've come up with an experiment using a plastic [music] predator.

30:00 I've never seen her see a snake, so I hope that she doesn't get too close.

30:04 Um, and that she lets us know that it's there and or make a small

30:09 noise like so that we know that there's something that she shouldn't go near.

30:16 Okay.

30:18 See, I'm really excited to find out exactly how she reacts to this.

30:23 Good girl, Kim Bang.

30:25 What's that?

30:26 Good girl.

30:37 You figure out what she's actually doing.

30:38 She's stopped.

30:39 So, she must have seen it.

30:41 Is she looking at it?

30:42 Yeah, she's definitely knows something's not quite right.

30:54 Yeah, look, she's moved right around.

30:57 She hasn't gone actually near the snake.

30:58 She's just checking [music] it from every angle.

31:03 This response is entirely based [music] on instinct.

31:07 There's a lot of snakes in this forest.

31:08 So, if she'd just gone and grabbed it, [music] then it would be really worrying.

31:15 You see, she just touched the boat to see if it would move.

31:18 Yeah.

31:18 Yeah, which is great.

31:20 Kim Bang adopts a defensive strategy.

31:24 She's even using the bush to make herself look even bigger.

31:29 Good girl.

31:32 She's improvising, using every tool at her disposal.

31:37 Oh, that's good.

31:38 She's trying to hit it with with the camera.

31:41 That's great.

31:44 But will she make an alarm call to announce the danger?

31:51 Yes, that [music] is brilliant.

31:56 It's great that she's let us know that it's there.

31:59 That is good.

32:00 So, I think we should make an alarm call so

32:02 she knows we've seen it and then she'll leave with us.

32:09 It's the perfect response,

32:12 one that could have saved her in a real life snake encounter.

32:15 Wallace turned his attention to the mind-boggling diversity of [music] insects.

32:24 To study one group thoroughly would,

32:26 in his opinion, deliver some definite results.

32:30 So, he set himself a punishing schedule of bug collecting.

32:38 I'm taking out my net lashed to a bit of bamboo.

32:41 It's heavy and a bit cumbersome,

32:43 [music] but hopefully it'll bag me some butterflies.

32:47 Wallace did this for hours and hours, day after day.

32:54 The trick is to keep your eye on the prize.

32:58 But that's the problem.

32:59 You can't see where you're stepping.

33:02 Then there's the humidity, the tropical heat,

33:05 not to mention the blood sucking leeches.

33:07 This is not some pretty pastime.

33:10 Oh,

33:11 it's extreme.

33:20 [music] The floor.

33:22 Come here.

33:22 Do that.

33:29 It's impossible.

33:33 Okay, time for a rethink.

33:35 I'm going to channel the spirit of Wallace.

33:38 Stay calm.

33:40 Pick my spot.

33:41 Wait for them to come to me.

34:04 Look at that.

34:06 I've caught a frog.

34:08 Brilliant.

34:12 It's not the uh intended quarry.

34:15 The frog, thinking he was safe, was some way downstream,

34:19 not realizing this is actually the Hodgekiss 4000B with detachable frog catcher,

34:28 thus uh surprising the frog.

34:30 I mean, look at it.

34:31 He looks surprised.

34:33 I did not expect that.

34:35 All right, I'm going to go.

34:39 Go on then.

34:40 Come on.

34:51 Ho ho.

34:52 That's the way to catch him.

34:56 This is actually a delicate little wood nymph.

35:03 It just takes me back to when I was about 10 years old trying

35:06 to catch purple emperors in the new forest and not succeeding because they were

35:11 all fluttering at the tops of the fur trees and you needed some special

35:14 extendable net to get there and I wasn't quite at that level of uh seriousness.

35:20 But me and my cousin spent many summers chasing butterflies.

35:26 It's quite a thrill when you get one in the net.

35:29 This is a beautiful sort of lacy translucent creature and it's

35:36 it just sort of flutters along gently in the forest really.

35:40 A lot of other butterflies are just hell

35:43 for leather like running in fear of their lives,

35:46 but this thing just seems to be taking its time.

35:48 I think because it's highly toxic, it it's lava feeds on poisonous leaves.

35:53 So, it's it's sort of I think it's maybe got a bit more swagger.

35:59 Yeah, you can eat me if you want, but you're going to pay.

36:06 Families have a new role to provide emotional support for mother and baby.

36:17 Nothing in the world is more important or brings greater joy.

36:31 [music]

36:46 Baby chimpanzees spend years learning about each other and their traditions.

36:52 Families are the schools.

36:54 [snorts] In central Africa, chimps crack nuts with rocks.

37:03 The trick is passed mother to baby down the generations.

37:07 It's part of their culture.

37:11 In East Africa, they catch termites using twigs.

37:19 Babies watch and learn.

37:26 They get the basics almost immediately.

37:28 It's something to do with a stick.

37:33 In some extraordinary footage,

37:35 the mother tries to help and is pushed away by the youngster.

37:41 With endless patience, she tries again.

37:44 No, not that huge thing here.

37:47 This one is better.

37:54 Only humans are supposed actively to teach,

37:58 but textbooks can be rewritten if necessary.

38:05 Young chimps get enormous pleasure from termite fishing.

38:08 A hunger to learn and satisfaction with success is also part of our biology.

38:14 It must drive a lot of what we do.

38:23 Most primates are born into troops, extended families, but not all.

38:31 A 2 kg newborn orangutan brings us back to the start.

38:40 Fathers and cousins are around, but not particularly helpful.

38:53 It'll be seven or eight years before the next one.

38:57 His mother's one of the world's slowest breeders.

39:03 His long childhood gives him time to work things out.

39:07 His mother will help map out where to find food,

39:10 and slowly he'll become aware of his world and himself.

39:21 It's not just primates.

39:23 It seems likely all mammals and maybe birds, too,

39:27 feel emotions and make thoughtful choices, particularly around babies.

39:37 Increasingly, boring face disaster.

39:40 [music] Infants that lose their mothers may be lucky enough to be rescued.

39:45 Human stepparents do their best with an orphan.

39:48 They both try to replace a bond that is lost.

39:55 Wallace was fascinated by the possibility

39:56 that humans and monkeys could be related.

40:01 And his belief was only reinforced when he came

40:04 across the man of the forest, the Orang Utan.

40:11 He spent weeks struggling to keep up with his tribal guides waste

40:15 deep in crocodileinfested swampy jungle trying to get close to these great apes.

40:21 Luckily, my guide Eric has a good idea where we might spot one.

40:29 Oh, there you see it between the branches over there.

40:35 Right between that big tree just behind.

40:38 Got it.

40:38 Yeah.

40:39 Ah.

40:40 Fantastic.

40:42 Look at that.

40:44 A good spot.

40:47 That's got to be a big male.

40:50 Can just see a huge hairy back and he's just

40:54 hanging out here waiting for the sun to come up.

40:58 Brilliant.

41:00 That's my first sighting of a Borneian orangutang and he's got his back to me.

41:12 Eric, Eric takes us in to give me a chance to see him face to face.

41:30 See, this sort of thing that I really admire about Wallace is that he

41:39 came through this jungle in the 1850s

41:45 with all manner of Victorian paraphernalia,

41:49 collecting jars around his neck, huge, heavy trunks and butterfly nets.

41:57 He was he was a tough cookie.

42:01 Trying to spot our orang from the forest floor isn't easy.

42:05 You'd think something the size of a man couldn't just disappear, but it can.

42:12 [music] Yeah.

42:30 this here.

42:31 Yeah.

42:31 Just a bunch of leaves sitting on the branch here.

42:43 [music] That's absolutely huge.

42:55 Okay, now he's on the move.

42:56 Yep.

42:57 That's following that.

43:11 Okay.

43:14 A fantastic view of it now.

43:15 Just just up here.

43:19 Yeah.

43:20 I just love the way that he just hangs out there.

43:26 He's [music] not really bothered with us.

43:28 He's just taking his time eating.

43:31 Just It's just amazing to see him in the wild.

43:34 I mean, it's one of those things I've always I've always wanted to do.

43:38 This is a This is a This is an extraordinary moment.

43:46 The thought of Wallace shooting these gentle giants I find deeply uncomfortable.

43:52 That was the Victorian way.

43:55 But unlike many of his contemporaries,

43:57 he also thought it important to observe them alive.

44:06 This is a poison dart frog.

44:10 Males raise their young in a very special way.

44:17 A father will place each one of his tadpoles in its own tiny pool of water.

44:24 This is one nice and safe.

44:31 He might have up to five other tadpoles,

44:36 but he needs to remember where he put each one of them.

44:43 This one isn't doing so well.

44:47 His tiny puddle has all but dried out.

44:51 The tadpo will die unless its father can find a better place for it.

44:59 If dads are good for one thing, it's piggyback rides.

45:14 Fathers are no bigger than a human thumbnail,

45:17 but this enables them to get to places that others can't.

45:23 This could be perfect.

45:31 The only problem is that there's no food here.

45:37 Fathers need help.

45:45 Somewhere in this forest is mom.

46:07 A female could do something a male cannot.

46:14 But first, dad must lead his partner to their hungry tadpole.

46:33 And mother deals with the problem.

46:39 She lays a single unfertilized egg.

46:51 and her tatpole gets a much needed meal.

46:58 For the next 6 weeks, parents continue their rounds.

47:02 An extraordinary test of teamwork and memory.

47:06 With little to eat down here,

47:08 many of Borneo's terrestrial mammals are smaller than on mainland Asia.

47:29 Confined to her protected forest sanctuary, the exceedingly rare Boraan sunbear.

47:44 Just over a meter long, it's the smallest bear in the world.

47:59 This fallen branch is a valuable treat.

48:06 Filled with wood grubs and beetles, nothing is wasted.

48:15 Even a foul tasting millipede.

48:26 But it's not enough to sustain even this little bear.

48:31 The real prize sits high above.

48:38 Guided by her exceptional sense of smell, it's the sweet scent of honey.

48:58 For larger bears, this beehive may be out of reach.

49:10 But being small helps defy gravity.

49:18 [music] With sharp claws and rough pads on her feet,

49:33 she can ascend 40 meters, higher than any other bear.

50:18 to make it in Borneo's jungle treetops.

50:24 This miniature acrobat has become more monkey than bear.

50:40 A thousand plants growing on one single tree.

50:46 Throughout the forest, this story is repeated endless times.

50:55 As a consequence, jungles are home to more species

50:58 of plants than anywhere [clears throat] else on Earth,

51:02 and they in turn support a wealth of animals.

51:12 In Ecuador, the competition is at its most intense.

51:18 Here there are 100 species of hummingbirds alone or fighting for nectar.

51:29 Each flower only has a small amount at any

51:32 one time and so it's first come first served.

51:40 One hummingbird has gone to great lengths to avoid conflict with other species.

51:50 Sword bills are the only bird with a beak longer than their body.

51:58 And some flowers are too elongated for the other

52:01 99 species of hummingbirds here to feed from them.

52:17 [music]

52:17 A sword build's extraordinary beak, however,

52:20 enables it to reach the places that others can't.

52:27 The top of this flower, where the sweet nectar is produced,

52:33 it has found a solution that means it doesn't have to join the fight.

52:40 And as each long flower blooms,

52:42 it gives the sword bill a [music] fresh supply of food all to itself.

52:56 [music] But having a beak longer than your body does have its drawbacks.

53:11 For a start, it's tricky to keep it clean.

53:26 Harder still, how do you pre your body feathers?

53:33 Unlike the other hummers,

53:34 sword bills can't reach their feathers with their beak.

53:45 The only option, a good old scratch.

53:51 [music] It's a little unrefined.

54:10 Have to defend themselves.

54:19 Every single plant in the rainforest has taken arms.

54:26 Some have evolved hooks, others vicious thorns,

54:36 and some have taken to chemical weaponry, filling their leaves with poisons.

54:58 planteaters have had to adapt to find a way around these defenses.

55:13 like this female three-toed sloth.

55:26 She has long, strong front legs to help [music] her climb around for food.

55:31 20 m up in the canopy.

55:49 Ligaments [music] bind her toes together, turning her claws into large hooks,

55:56 so she hangs from a branch without spending [music] much energy.

56:10 This bizarre body has developed as one big adaptation to a specialized diet.

56:21 She eats just a few kinds of tree.

56:33 These tough leaves contain inedible toxins that most animals can't digest.

56:48 Her gut has developed a special system of pouches

56:52 to separate food in various stages of digestion.

56:56 And it hosts specialized bacteria that break down the leaves.

57:02 But digesting can take weeks.

57:06 [music] This means she only has space to eat

57:15 a very small helping of leaves a day, the weight of a small egg.

57:20 [music] [music] She gets so little energy from this diet

57:29 that she must keep movement to a minimum.

57:34 This explains the famous slowness of slos.

57:40 She has almost become part of the forest

57:42 furniture and other creatures have started to move in.

57:57 She has become the ideal [music] home for a colony of sloth moths.

58:09 To help her in her quest, she's equipped with three superpowers.

58:16 First, an amazing [music] approach to getting about.

58:26 Porsche is a jumping spider, able to leap up to 50 times her own body length.

58:40 Nowhere seems beyond her reach.

58:46 Next, her second superpower, superb eyesight.

58:52 Essential if she's to distinguish her prey in all this clutter,

58:59 because her prey doesn't stray.

59:06 Porsche is a spider eating spider.

59:13 This raises a few problems.

59:16 Her lunch is three times her size,

59:21 packed with venom, and surrounded by a sticky trap.

59:30 Mission impossible?

59:32 Not at all.

59:34 Because of her third superpower, Porsche is a genius.

59:44 She can map her world in three dimensions and formulate a plan of attack.

59:54 She can have an idea.

1:00:15 The web builder is blind.

1:00:20 It won't have a clue that she's coming.

1:00:46 Right on target and safely behind those fangs.

1:00:59 But a mind as active as Porsches can always do with more brain food.

1:01:09 Here there's no anchor point for the abail.

1:01:16 But Porsche has another idea.

1:01:22 Instead of going to the spider, [music] she will bring the spider to her.

1:01:37 She plucks the strands to imitate struggling prey, drawing the spider in.

1:01:52 to its death.

1:01:57 The longer Wallace spent on Silhouazi, the more it puzzled him.

1:02:02 The couscous and Tarsas weren't the only curiosities.

1:02:07 So many bizarre creatures here were unique.

1:02:10 Found nowhere else in the world.

1:02:16 And it was on this very beach more than 150

1:02:20 years ago that Wallace encountered one of the strangest of all.

1:02:25 Silhouazi macaks.

1:02:31 They really are quite oddlooking creatures.

1:02:33 Small, compact, jet black fur and as Wallace wrote,

1:02:36 about the size of a spananiel.

1:02:38 They got this strange hair and big foreheads

1:02:41 and a permanent look of surprise on their faces.

1:02:44 They really are peculiar looking creatures.

1:02:51 What?

1:02:54 Okay, so maybe there is a passing resemblance.

1:02:59 He wrote how they would stare at him in astonishment as he went collecting.

1:03:06 Turn monkey incoming.

1:03:14 We've obviously uh attracted a bit of attention here.

1:03:17 We've got the whole family's turned up to have a look at this.

1:03:28 And they haven't lost that natural curiosity.

1:03:40 He's just checking me out.

1:03:51 Well, I'm obviously been accepted as part primate.

1:03:59 Wallace had encountered other species of macaks on his travels.

1:04:04 All were brown and had tails,

1:04:08 but their cousins on silhouise were black and tailless and they had moheakans.

1:04:19 Wallace wanted to understand why these monkeys

1:04:22 and the other creatures here were so different.

1:04:25 Something about this island drove species to change.

1:04:30 In these forests lives a bird that is about

1:04:33 as unbirdlike as it is possible for a bird to be.

1:04:42 It's nocturnal though it [music] sometimes wakes up before sunset.

1:04:50 [music] It has whiskers so it can feel its way in the dark.

1:04:56 [music] It's a parrot [music] and weighing up to 4 kilos,

1:05:04 it's the world's heaviest.

1:05:11 [music] And yes, you've guessed it.

1:05:15 It can't fly.

1:05:20 [music] Meet the kakao.

1:05:27 [music]

1:05:32 Too heavy [music] and short-winged to get airborne, it climbs trees instead.

1:05:38 [music] [music] Kakapo were once one of the most

1:05:51 successful [music] and abundant herbivores in New Zealand.

1:05:54 The kiwi equivalent of our rabbit.

1:05:57 In 1899, explorer Charlie Douglas wrote,

1:06:00 "They could be caught in the moonlight by simply shaking

1:06:03 the tree or [music] bush until they tumbled to the ground,

1:06:06 like shaking down apples.

1:06:17 [music] Its favorite food is up above the tiny seeds of the reu tree.

1:06:30 This fruit fuels kakapo reproduction and they only

1:06:33 breed when the trees produce a bumper crop.

1:06:36 So about once every four years, kakapo breed slower than any other bird,

1:06:45 but they also live longer, sometimes more than a 100red years.

1:06:56 The male's song is as peculiar as the bird itself, more frog than parrot.

1:07:03 It can be heard up to 5 km away.

1:07:07 In a breeding season,

1:07:08 he will boom non-stop for 8 hours every night for up to 3 months.

1:07:17 But a female will only respond if there are plenty of Remu seeds about.

1:07:24 So, while these birds may nest in burrows like rabbits, unfortunately,

1:07:28 they don't breed like them and their numbers have dwindled dramatically.

1:07:36 Today, fewer than a 100 kaka survive.

1:07:39 Each autumn, a squirrel buries around 10,000 nuts.

1:07:44 Its memory is so phenomenal, it can retrieve up to 4,000 of them.

1:07:50 To achieve this feat, as winter approaches,

1:07:53 the area of the brain responsible for memory enlarges 15%.

1:07:59 The squirrels show another brainy trait, cunning.

1:08:05 A spy squirrel bearing gifts is ready to record their devious behavior.

1:08:16 He looks a soft touch, but the squirrel needs to be sure.

1:08:23 He lashes his tail to show confidence.

1:08:28 Fluffing it up makes him appear bigger and shows who's boss.

1:08:45 Spy squirrel is a pushover.

1:08:47 He's going to be popular.

1:08:50 The nut is immediately stashed away.

1:08:54 But clever minds can also be devious.

1:08:57 [music] And this squirrel watches where the nut is hidden.

1:09:05 As soon as it's buried, she makes her move.

1:09:16 Okay, if you don't get caught, but there's big trouble if you do.

1:09:25 Yeah.

1:09:48 The duped squirrel [music] needs to be craftier this time.

1:09:58 [music] The crook may still be watching, but this is what [music] he wants.

1:10:02 In a shameless display of overacting, he pretends [music] to bury his nut.

1:10:13 [music] The thief waits until the performance is over.

1:10:23 then quietly sneaks in.

1:10:28 But there's no nut to piler here.

1:10:31 Hardly surprising.

1:10:32 It's stashed in his intended victim's mouth.

1:10:40 With the nut raider preoccupied, he can either eat it or bury it secretly.

1:10:47 But the thief hasn't abandoned her life of crime.

1:10:52 Spy squirrel has a new nut.

1:10:55 One with a camera.

1:11:00 Theft is such an easy option around a fifth

1:11:03 of all squirrels steal nuts rather than forage for them.

1:11:11 It's a crafty way of letting others do the hard work.

1:11:18 But this time, the thief has picked the wrong nut.

1:11:29 This tiny poison arrow frog is carrying his tadpole pickerback.

1:11:34 It hatched on a leaf and now he's taking it

1:11:37 to a pool in a bromeilad high up in the branches.

1:11:42 The tadpole wrigles off.

1:11:45 He may have half a dozen babies, each of which he puts into its own tiny pool.

1:11:59 He makes regular tours of all his nurseries, checking on his tadpole's welfare.

1:12:13 This youngster is hungry and tells him so

1:12:16 by nibbling his legs and vibrating against his body.

1:12:25 But the male can't feed the tadpole himself.

1:12:28 He needs help.

1:12:39 He has to find a female.

1:12:51 There she is.

1:12:57 He calls and she follows.

1:13:17 He has to lead for only he knows exactly where he deposited each tadpole.

1:13:25 This one is now very hungry indeed.

1:13:33 He calls to the female encouragingly.

1:13:41 She jumps in perhaps to assess the situation.

1:13:48 Out she comes without having done what's required.

1:13:52 So he keeps calling.

1:13:55 In she goes a second time.

1:13:58 This time she produces food for the hungry tadpole.

1:14:02 An infertile egg.

1:14:08 There out she comes.

1:14:16 And mother and father embrace.

1:14:31 Baby has its dinner.

1:14:36 Jungle hut.

1:14:37 This female finds a saw.

1:14:45 Despite being totally wild, somehow she has worked out what to do with it.

1:14:55 Like us, orangutans have an opposable thumb that allows

1:14:58 them to grasp and handle objects with precision.

1:15:04 Over 20 years ago, a rescue orangutan learned how

1:15:07 to saw by watching people constructing the huts here.

1:15:11 But this is a totally different and wild orangutan.

1:15:16 She seems to take pride in her work, even clearing away the sawdust.

1:15:31 She's so smart, she uses her feet as a vice to steady the branch.

1:15:40 Filming a wildorn and freeliving orangutang

1:15:43 mastering this complex task is remarkable.

1:15:51 But now she's not the only orangutan sawing.

1:15:58 Spy orangutan has joined her.

1:16:08 It seems to be bringing out a competitive streak.

1:16:11 She's becoming even more enthusiastic.

1:16:21 [music] [music] But for a novice, sewing is tiring work.

1:16:36 She's lost all momentum.

1:16:43 Then finally calls it a day.

1:16:47 Spy orangutan may have machine-like stamina,

1:16:50 but it's the astonishing and versatile mind

1:16:52 of the real orangutan that's won the day.

1:16:55 She certainly earned her rest.

1:16:58 The army ant.

1:17:03 This may look [music] like a ball of a million individuals,

1:17:06 but make no mistake, the colony acts as one.

1:17:14 A super organism with a sensory system of two million antenna.

1:17:21 A skeleton made from the living bodies of workers.

1:17:29 A defense system of soldier ants ready to act at any sign of danger.

1:17:38 A digestive system processing piles of food deep inside.

1:17:46 even a coordinated [music] system for dealing with all the waste.

1:17:54 These are insects that [music] by working together transcend individual size.

1:18:02 The colony can search [music] the entire jungle and flush out its wildlife.

1:18:17 Each day it sends [music] out a silent probe into the forest in quest of food.

1:18:30 It doesn't use scouts like other ants.

1:18:37 Instead, a vast search party pushes into virgin territory,

1:18:47 seeking out the signs of anything alive.

1:19:02 They spread out along a 10 m front, sweeping across the forest floor.

1:19:11 To find prey, the ants must first touch it.

1:19:16 The irony is that this, the most successful hideandsek player in the forest,

1:19:21 is almost [music] completely blind.

1:19:26 It distinguishes the living only by their movement.

1:19:33 As long as an animal remains still, it is safe.

1:19:40 But the slightest twitch will give it away.

1:19:47 [music] Within seconds, the prey is pinned down.

1:19:54 Within minutes, it's torn apart at its joints.

1:20:02 [music] The more the prey struggles, the more the ants engage.

1:20:09 [music] Right across the raid front,

1:20:13 prey of all sizes are driven from their hiding places.

1:20:21 Even wasps must abandon their homes when the ants arrive.

1:20:30 Everything alive in the path of the raiders, overwhelmed by sheer numbers.

1:20:40 The most I've ever seen in my life.

1:20:45 [music] Deep in the rainforests of Costa Rica, life can be difficult.

1:20:51 From the heat of the dry season [music]

1:20:53 to the relentless rain of the wet season,

1:20:56 conditions here can be brutal to film in.

1:20:58 [music] For the Planet Earth 3 crew arriving

1:21:02 at the start of the wet season, it's tough.

1:21:10 But for these gliding tree frogs that they're here to film,

1:21:13 the start of the wet season triggers their explosive mating [music] events.

1:21:22 This year, however, the most important ingredient has been sorely lacking.

1:21:28 Rain.

1:21:29 It's insane.

1:21:29 I've literally never seen the pond so dry before.

1:21:32 Gliden tree frogs really need uh intense rain.

1:21:35 They need hours and hours of rain

1:21:36 in the afternoon and the evening to trigger their breeding.

1:21:40 They need to come down to the pond to breed

1:21:42 because they need to lay their eggs over a water source.

1:21:45 So, what we have to do now is just wait for the rain

1:21:48 and wait for the pond to fill up and wait for the frogs.

1:21:51 And so, the wait begins.

1:21:54 So, it's day 10 and there still hasn't been any rain.

1:21:56 So, the pond is completely dry and there's no mating.

1:21:59 It's quite frustrating waiting every day.

1:22:01 Um, there's not much to do apart from just wait for the frogs to arrive.

1:22:05 Wait for the rain to arrive.

1:22:06 It's not a cloud in the sky.

1:22:07 I It's crystal.

1:22:08 It's beautiful really, but not for what we want.

1:22:11 Now, I am getting a little bit concerned.

1:22:15 Finally, 24 days into the shoot.

1:22:22 [music] It's raining.

1:22:27 The rains have finally arrived.

1:22:28 So, this is great.

1:22:29 And it's really heavy.

1:22:30 If this lasts overnight, then tomorrow it's on.

1:22:33 [music] So, fingers crossed tomorrow might be our day.

1:22:45 5:00 a.m.

1:22:46 A chorus of frog calls.

1:22:49 They're here.

1:22:52 Carefully, the team make their way to the site.

1:22:55 The pond is definitely full.

1:22:59 Amongst calls from a plethora of frog species,

1:23:02 including the gliding tree frog itself,

1:23:04 the team set up, and time is of the essence.

1:23:09 Equipment primed and in place, the shoots can finally begin.

1:23:20 These mating events are just like absolute chaos.

1:23:22 There are thousands of thousands of frogs piled onto

1:23:25 just a few leaves where it's the most dense.

1:23:28 Uh we have frogs on the camera lens.

1:23:30 We've got frogs like all our equipment.

1:23:33 They are looking.

1:23:34 [screaming] It's really an amazing spectacle to witness.

1:23:38 The males vastly outnumber the females and scramble in search of a suitor.

1:23:44 But large clusters known as mating balls are created by all this attention.

1:23:49 One slip can be a one-way ticket for these cayman lurking below.

1:23:59 It's an easy meal.

1:24:06 The less patient also have ways of snapping up the frogs.

1:24:18 But in the leaves above, the action continues.

1:24:23 Successful males and their partners head to a nearby leaf where

1:24:26 the female lays her eggs and the male then fertilizes them.

1:24:33 Once the [music] tadpoles have had time to mature,

1:24:35 they emerge, ready to take the plunge.

1:24:40 [music] [music] The seasonal pond now provides a home

1:24:51 for thousands of future gliding tree frogs [music] for the crew.

1:24:58 The weight and the wets have been worth it.

1:25:02 I feel relieved.

1:25:03 We've got everything we need today.

1:25:04 The frogs were great.

1:25:06 It's so incredible to see.

1:25:07 We had a really great mating event.

1:25:08 They gave us enough time to get everything we needed.

1:25:10 It's the most amount of frogs I've ever seen in my life.

1:25:14 Termites, an important source of protein,

1:25:34 but perhaps they are an acquired taste.

1:25:53 He's off to search for something he might prefer.

1:26:11 It's hard to know where to look.

1:26:27 Or where it's safe to clamber.

1:26:41 Different levels in the forest contain different foods.

1:26:47 And some of the most delicious are in the very highest parts of the canopy,

1:26:52 50 m above the ground.

1:27:05 He's a couple of years old and he's already getting adventurous.

1:27:12 His mother could climb right to the top [music] in 10 minutes or so

1:27:16 if she wanted to, but she lingers to keep an eye on him.

1:27:26 A fall from this height could be fatal.

1:27:40 Where the gaps between the branches are too wide for him,

1:27:43 his mother lets him use her body as a bridge.

1:28:03 Only 10 m to go before the top, but it's hard going for small hands.

1:28:30 He's had enough.

1:28:41 Time for a rest with mother.

1:28:57 And this is his reward.

1:29:00 [music] [music] Meadows that only a few weeks ago were

1:29:18 buried beneath the snow are now full of life.

1:29:24 [music] But in these mountains, the good times will not last long.

1:29:46 So the bears must feed as fast as they can.

1:29:52 During the summer months, an adult can put on 180 kilos gorging on plants.

1:29:59 And if they can catch them, a moment or two.

1:30:08 But just now, the bears have something else on their minds.

1:30:16 It's becoming warmer, and the bears are keen to shed their thick winter coats.

1:30:21 [snorts] Mothers show the culls what to do about this.

1:30:37 They'll soon catch on.

1:30:42 Some trees, it seems, are particularly suitable for rubbing.

1:30:47 Bears have their favorites and will travel long distances to visit them.

1:30:55 Some itches just have to be scratched.

1:31:01 [music] [music] [music] There are now around 30 bears in this one valley.

1:31:26 [music] As they rub, each leaves an individual and recognizable scent.

1:31:38 So, the tree soon carries a list of who's around,

1:31:43 which might help individuals to avoid a fight.

1:31:47 To best spread their scent, they only have to put their back into it.

1:31:52 [music] [music] Oh, [music] [music] [music] heat, heat.

1:32:34 But summer is short.

1:32:36 Itches satisfactorily scratched.

1:32:40 It's time to eat.

1:32:45 In a couple of months, they will have to return to their dens to hibernate.

1:32:49 So now they must put on as much weight as they can.