0:00:10 > 0:00:13Let's face it, our world is downright weird.
0:00:15 > 0:00:17Oh!
0:00:17 > 0:00:20Crawling with creatures you've never heard of...
0:00:20 > 0:00:23I can't believe that's a living thing.
0:00:23 > 0:00:25..full of the unexpected...
0:00:27 > 0:00:31..like freak weather exploding out of the blue...
0:00:31 > 0:00:33I thought I was going to die.
0:00:33 > 0:00:36..and rocks that spontaneously combust...
0:00:36 > 0:00:39I thought it was dynamite going off.
0:00:39 > 0:00:41..and the unexplained.
0:00:41 > 0:00:46An unborn twin, discovered inside a brain.
0:00:46 > 0:00:50There was multiple hair follicles, bone and teeth.
0:00:54 > 0:00:58We scoured the globe to bring you the very weirdest stories.
0:00:58 > 0:01:00Ah!
0:01:01 > 0:01:03I could feel this intense pain,
0:01:03 > 0:01:07as if you were being stabbed by hundreds of syringes.
0:01:12 > 0:01:15In this series, we're going to examine the evidence,
0:01:15 > 0:01:19test the science and unravel the mysteries.
0:01:19 > 0:01:24We're going to discover what in the weird world is going on?
0:01:35 > 0:01:38In this episode, we'll uncover the secrets
0:01:38 > 0:01:42to some of the natural world's weirdest mysteries.
0:01:45 > 0:01:49How could the sun's rays exterminate birds in flight?
0:01:52 > 0:01:55And why have these monkeys become trained in first aid?
0:01:58 > 0:02:02Exactly how do you get spider silk from a goat?
0:02:03 > 0:02:08And how far would a porcupine go, to find true love?
0:02:14 > 0:02:17Well, it all starts here.
0:02:20 > 0:02:25Nevada, long-time home of the weird.
0:02:25 > 0:02:29You know, for decades, this place has been home to unexplained
0:02:29 > 0:02:34sightings, bizarre conspiracy theories.
0:02:34 > 0:02:38But in 2013, something every bit as weird,
0:02:38 > 0:02:41but very real, happened in the skies here.
0:02:45 > 0:02:49A local photographer captured these strange explosions.
0:02:53 > 0:02:56I saw these objects going across the frame of the video.
0:02:56 > 0:02:59Sometimes they would change direction, sometimes they'd
0:02:59 > 0:03:03go up, sometimes they'd go down and I didn't know, at first,
0:03:03 > 0:03:04what they were.
0:03:06 > 0:03:07Sometimes they would dive down,
0:03:07 > 0:03:10maybe like it was trying to escape from something.
0:03:10 > 0:03:14Sometimes it would turn around and go in the other direction.
0:03:14 > 0:03:16So, what were they?
0:03:16 > 0:03:18What was going on?
0:03:18 > 0:03:21It was clearly too early in the day for fireworks.
0:03:21 > 0:03:23Military testing, perhaps?
0:03:23 > 0:03:28I examined the videos closely and I was able to see a little
0:03:28 > 0:03:32flapping motion, which was their little wings were flapping.
0:03:35 > 0:03:40Wildlife officials found the bodies of birds,
0:03:40 > 0:03:43birds that had fallen to their death from clear skies.
0:03:47 > 0:03:51Now, mass bird deaths, although shocking, are not that unusual.
0:03:53 > 0:03:58Poisoning and collisions like this plane strike
0:03:58 > 0:04:01can bring down flocks of birds.
0:04:04 > 0:04:07But the reports from Nevada were different.
0:04:08 > 0:04:11They found about 83 different species of birds.
0:04:14 > 0:04:18Everything from very small birds like hummingbirds to doves,
0:04:18 > 0:04:21to larger birds like ravens, and raptors, like peregrine falcon.
0:04:23 > 0:04:26A bizarre collection of different species,
0:04:26 > 0:04:29but with one thing in common.
0:04:29 > 0:04:33The feathers were sort of melted and they were in fragments.
0:04:33 > 0:04:38The birds were all burned alive.
0:04:40 > 0:04:43What a gruesome way to go.
0:04:43 > 0:04:45What could have caused this?
0:04:46 > 0:04:49It's a conundrum worthy of Area 51,
0:04:49 > 0:04:56but it is one that can be explained via a quick trip over the pond.
0:04:59 > 0:05:03September 2013, central London.
0:05:03 > 0:05:05We've had temperatures of up to 50 degrees Celsius
0:05:05 > 0:05:08in the last few minutes and if I just look at the current
0:05:08 > 0:05:10temperature, well, it's still 42 degrees.
0:05:12 > 0:05:14People have been trying to cook eggs.
0:05:14 > 0:05:17My colleague realised there was a smoke coming out. He smelt it.
0:05:17 > 0:05:20We looked back and the carpet was on fire.
0:05:20 > 0:05:24Melted bicycles, burned cars...
0:05:24 > 0:05:26We realised it was from the big building.
0:05:26 > 0:05:30..and all fingers pointed at the building above that was
0:05:30 > 0:05:34burning a hot spot on the pavement below it, but how?
0:05:41 > 0:05:45Now, we all know that mirrored surfaces reflect sunlight
0:05:45 > 0:05:50and when they're curved, they focus this into a central point
0:05:50 > 0:05:54where it becomes a much more powerful beam.
0:05:57 > 0:06:02That's what was happening with that London tower block.
0:06:02 > 0:06:06It was focusing the beam down onto the pavement where it was hot
0:06:06 > 0:06:09enough to damage stationary objects.
0:06:10 > 0:06:13It's impressive,
0:06:13 > 0:06:18but it's still not enough to set fire to birds in flight.
0:06:18 > 0:06:21For that, you'd have to seriously upscale.
0:06:26 > 0:06:28This isn't a mirage.
0:06:32 > 0:06:37This is Ivanpah, a power plant with a difference.
0:06:42 > 0:06:48300,000 mirrors reflect the desert sun onto a central tower.
0:06:50 > 0:06:57Boiling water to create steam which then generates energy.
0:07:03 > 0:07:07It's an undeniably beautiful piece of engineering,
0:07:07 > 0:07:10but with an unexpectedly deadly side-effect.
0:07:11 > 0:07:15Now, we can demonstrate the power of Ivanpah, right here.
0:07:24 > 0:07:28EERIE MUSIC
0:07:44 > 0:07:46Ivanpah in miniature.
0:07:48 > 0:07:51These tiny mirrors reflect the light.
0:07:53 > 0:07:55But, crucially, it's not scattered.
0:07:55 > 0:07:58The mirrors are perfectly angled.
0:08:00 > 0:08:04It's a parabolic curve focusing the light onto a centre point.
0:08:09 > 0:08:13And turbo charging that light and the heat intensity.
0:08:19 > 0:08:25Now, it's hot enough to roast wood, even melt lead.
0:08:29 > 0:08:32And feathers, well, they simply don't stand a chance.
0:08:37 > 0:08:40But that, on an industrial scale,
0:08:40 > 0:08:44out here in this desert, under that sun,
0:08:44 > 0:08:47the power generated is off the scale.
0:08:51 > 0:08:55As the desert sun hits Ivanpah's 300,000 mirrors,
0:08:55 > 0:08:57the light is reflected towards the towers,
0:08:57 > 0:09:02creating temperatures of up to 1000 degrees Centigrade.
0:09:04 > 0:09:09The experiment in green energy had created a solar death ray.
0:09:11 > 0:09:16So, what can the plant do, to solve this very sad problem?
0:09:16 > 0:09:19They've been willing to modify their software system.
0:09:19 > 0:09:23They've also been working to test out deterrent systems to scare
0:09:23 > 0:09:27birds away from the danger zone around the towers.
0:09:27 > 0:09:30Let's hope they find a solution that works.
0:09:35 > 0:09:40So, this tragic loss of avian life is testament to the awesome
0:09:40 > 0:09:42power of the sun.
0:09:42 > 0:09:44It just makes you wonder, doesn't it,
0:09:44 > 0:09:47what else the sun is responsible for?
0:09:51 > 0:09:55How about changing the landscape of musical history?
0:09:58 > 0:10:03In the 1600s, Antonio Stradivari took a piece of spruce
0:10:03 > 0:10:05and made a violin.
0:10:07 > 0:10:12Today, his instruments are the most famous on the planet.
0:10:12 > 0:10:15Every music collector wants to own one
0:10:15 > 0:10:18and every dealer wants to get their hands on one.
0:10:18 > 0:10:20When I pick up one of these instruments,
0:10:20 > 0:10:24there's always something a bit special and magic about it.
0:10:26 > 0:10:30An instrument from the golden period, which this instrument is from,
0:10:30 > 0:10:33could be worth from a few million dollars to 12 million dollars
0:10:33 > 0:10:39or 15 million dollars and if it's a great one, oh!
0:10:39 > 0:10:41142,000, 145,000...
0:10:41 > 0:10:46Wow. And their desirability is down to one thing - sound.
0:10:53 > 0:10:56It's got a real magic aura to it
0:10:56 > 0:11:00and it's partly for that reason that people have tried to figure
0:11:00 > 0:11:03out what's the so-called secret of Stradivari.
0:11:11 > 0:11:15Yes. For 300 years, craftsmen have tried to discover
0:11:15 > 0:11:18the secret to Stradivari's sound.
0:11:21 > 0:11:23They've tested every theory.
0:11:25 > 0:11:29The wood has been soaked in seawater or the varnish has volcanic ash
0:11:29 > 0:11:31in it, was another one I remember.
0:11:31 > 0:11:34But they've all failed, until, that is...
0:11:37 > 0:11:39..a scandal hit the headlines.
0:11:44 > 0:11:48Now, Stradivari's most famous violin is known as the Messiah
0:11:48 > 0:11:53and it's aptly named, apparently, because those in the know,
0:11:53 > 0:11:56claim that it's the world's ultimate violin.
0:11:56 > 0:12:00But back in 1999, someone had the temerity to
0:12:00 > 0:12:05suggest that this priceless piece of musical history, wasn't
0:12:05 > 0:12:09the real deal, that Stradivari hadn't made it, that it was a fake.
0:12:11 > 0:12:14Now, let's just put that in perspective.
0:12:14 > 0:12:17That's a bit like saying that Leonardo da Vinci didn't
0:12:17 > 0:12:22paint the Mona Lisa, that John Lennon didn't write Imagine.
0:12:24 > 0:12:29The classical musos were in absolute uproar.
0:12:30 > 0:12:32To calm the clamour,
0:12:32 > 0:12:36the Messiah was brought under the scrutiny of a specialist.
0:12:36 > 0:12:39It was a thrilling moment, for me, when they took it out of the case.
0:12:39 > 0:12:43I have gloves on and they put it in my hands and said,
0:12:43 > 0:12:46"Here is a musical instrument worth millions of dollars.
0:12:46 > 0:12:47"Do what you want with it."
0:12:50 > 0:12:55Henri and his team studied the unique rings of the Messiah's wood.
0:12:55 > 0:12:58We use pattern matching in the tree rings sciences, to determine
0:12:58 > 0:13:00when these tree rings were formed.
0:13:02 > 0:13:06The rings of the Messiah matched perfectly with samples
0:13:06 > 0:13:09taken from the Stradivari Forest.
0:13:09 > 0:13:14When I saw that, I knew that this was not a fake, it was not a copy.
0:13:14 > 0:13:16This was an instrument that was contemporary with
0:13:16 > 0:13:19Antonio Stradivarius and in all likelihood,
0:13:19 > 0:13:21was made by Antonio Stradivarius.
0:13:23 > 0:13:28So, it was the Messiah's wood that gave the world's most famous
0:13:28 > 0:13:32violin its ring of authenticity.
0:13:32 > 0:13:33But I've got to tell you, that those
0:13:33 > 0:13:37rings revealed something far more exciting.
0:13:37 > 0:13:41Now, remember I was talking about the sun. Well, stick with me.
0:13:42 > 0:13:47Right, we know that every ring represents a year in a tree's life,
0:13:47 > 0:13:51but the thickness of each ring is just as important.
0:13:52 > 0:13:55A wide ring tells us that during that year,
0:13:55 > 0:13:57the tree grew very quickly.
0:13:59 > 0:14:02But a thin ring means exactly the opposite.
0:14:02 > 0:14:05That means the tree grew slowly.
0:14:07 > 0:14:11And the Messiah had incredibly thin rings.
0:14:11 > 0:14:15So tightly packed, that the wood was three times more dense
0:14:15 > 0:14:17than that of a modern instrument.
0:14:17 > 0:14:21Dense enough to create an exceptional sound.
0:14:24 > 0:14:28But why was that wood so extraordinarily dense?
0:14:29 > 0:14:32And what on earth has the sun got to do with it?
0:14:37 > 0:14:40Well, when Stradivari was making violins in the Italian Alps,
0:14:40 > 0:14:45the sun was behaving very strangely.
0:14:45 > 0:14:51Between 1300 and the late 1800s, its power was reduced.
0:14:51 > 0:14:52Lakes froze...
0:14:55 > 0:14:56..the days darkened.
0:14:58 > 0:15:00It was a little Ice Age.
0:15:07 > 0:15:10Now, the Little Ice Age might be news to you
0:15:10 > 0:15:11but it actually happened.
0:15:11 > 0:15:16In fact, it got so cold during the winter times that the Thames
0:15:16 > 0:15:18froze over.
0:15:18 > 0:15:22Now, imagine you are a tree growing somewhere in the Alps
0:15:22 > 0:15:27but growing quite close to a famous violin maker's house.
0:15:27 > 0:15:31You're using every last little bit of that sunshine,
0:15:31 > 0:15:32but it's difficult,
0:15:32 > 0:15:36which means you're growing very, very slowly indeed.
0:15:36 > 0:15:39It's starting to fall into place.
0:15:45 > 0:15:49Henry's theory is that the sun, or the lack of it,
0:15:49 > 0:15:54created super-dense, super-musical spruce.
0:16:00 > 0:16:05So, solar starvation could be the secret for the Stradivarius's
0:16:05 > 0:16:07beautiful and unique sound.
0:16:08 > 0:16:13But of course, the world's finest violin wouldn't be any good
0:16:13 > 0:16:16without the world's finest violin strings.
0:16:17 > 0:16:22In 2012, a Japanese researcher decided to produce the world's most
0:16:22 > 0:16:25beautiful violin string.
0:16:25 > 0:16:29Instead of using the traditional gut or metal,
0:16:29 > 0:16:33Dr Osaki wove 15,000 strands of silk.
0:16:35 > 0:16:39RADIO TUNING
0:16:39 > 0:16:41VIOLIN MUSIC
0:16:41 > 0:16:42I know what you're thinking.
0:16:42 > 0:16:45You're thinking, "That still sounds like a violin,"
0:16:45 > 0:16:46but it's a little bit softer.
0:16:47 > 0:16:50RADIO TUNING
0:16:50 > 0:16:54And to trained ears...
0:16:54 > 0:16:57it's more profound.
0:16:57 > 0:17:03Which is downright weird, because Dr Osaki isn't a musician.
0:17:03 > 0:17:05He's a medical researcher
0:17:05 > 0:17:09and he made the strings with the help of his lab partners.
0:17:11 > 0:17:14300 orb web spiders.
0:17:21 > 0:17:25Their silk fibres combined together are tough enough to be played.
0:17:27 > 0:17:31And Dr Osaki puts the string's unique sound down to the way
0:17:31 > 0:17:35the fibres compact together leaving barely any air gaps
0:17:35 > 0:17:37between the strands.
0:17:43 > 0:17:47It's not really my sort of thing, but I'm growing to like it.
0:17:47 > 0:17:52But with 15,000 strands of silk in every single string,
0:17:52 > 0:17:56it's unlikely that they're ever going to hit the mass market.
0:17:56 > 0:18:01It would be impossible to kit out a fully-fledged orchestra.
0:18:02 > 0:18:06Unless, of course, you had a spider silk making factory.
0:18:06 > 0:18:09But then, that's a ludicrous idea...
0:18:09 > 0:18:11isn't it?
0:18:13 > 0:18:14Well, no.
0:18:14 > 0:18:17Not for one extraordinary scientist, who's discovered
0:18:17 > 0:18:20the secret of spider-silk manufacturing.
0:18:22 > 0:18:25Spider silk is the strongest fibre that's found in nature.
0:18:25 > 0:18:28Has a tensile strength greater than Kevlar
0:18:28 > 0:18:31and has an elasticity or elongation greater than nylon.
0:18:33 > 0:18:35So, it means we can use it for different medical
0:18:35 > 0:18:39products like artificial ligaments, artificial tendons, hard body parts.
0:18:39 > 0:18:42For airplane parts, even for protective clothing.
0:18:44 > 0:18:49A silk aeroplane, you'd need tonnes of the stuff.
0:18:49 > 0:18:52But Randy's not running a spider sweatshop.
0:18:52 > 0:18:55So, the problem with using spider silk from spiders themselves
0:18:55 > 0:18:57is the spiders can't be farmed.
0:18:57 > 0:18:59They're territorial, they're cannibalistic, so,
0:18:59 > 0:19:02if you put a lot of them together, they kill each other until everybody
0:19:02 > 0:19:04has enough room, so you've got to come up with
0:19:04 > 0:19:06another manufacturing method.
0:19:10 > 0:19:14Born and bred in Utah, Randy has farming in his blood.
0:19:16 > 0:19:20Goats are his thing and although they might look normal,
0:19:20 > 0:19:24these goats are anything but normal.
0:19:24 > 0:19:28You see, inside their cells is a little something extra.
0:19:28 > 0:19:29Something spidery.
0:19:31 > 0:19:37The majority of these goats have a gene in them that came from a spider.
0:19:42 > 0:19:44We took the DNA for the spider-silk gene.
0:19:44 > 0:19:47That DNA was then injected into an embryo
0:19:47 > 0:19:51and we take the embryos and we implant them into a...
0:19:51 > 0:19:54into an accepter female and five months later,
0:19:54 > 0:19:55she has a baby goat for us.
0:19:58 > 0:19:59Real-life spider kids...
0:20:01 > 0:20:05..that will grow up to produce spider silk in their milk.
0:20:14 > 0:20:17Now, this isn't actually as weird as you might first think
0:20:17 > 0:20:21because spider silk, when in the spider, is also a liquid.
0:20:23 > 0:20:27But I have to say, this is where the similarity ends,
0:20:27 > 0:20:29because spiders have special spinnerets that spin
0:20:29 > 0:20:32the liquid into solid lines of silk.
0:20:35 > 0:20:39But how do you get silk out of a goat?
0:20:39 > 0:20:40So, we take the milk from the goats here.
0:20:40 > 0:20:43We take it back to the lab and we purify
0:20:43 > 0:20:45the spider-silk protein out of it.
0:20:45 > 0:20:48And then we try to mimic what the spider does in terms of actually
0:20:48 > 0:20:51making the fibre so we try to spin it
0:20:51 > 0:20:54so that we pull it instead of pushing it out.
0:20:54 > 0:20:57Then we stretch it, which is exactly the same thing that a spider does.
0:21:00 > 0:21:02This year's crop of kids look cute now,
0:21:02 > 0:21:08but soon they'll be spider-goat silk-making machines.
0:21:08 > 0:21:12So, our very best goat makes about four grams of spider-silk
0:21:12 > 0:21:14protein per litre.
0:21:14 > 0:21:18She produces about eight litres per day, so about 32 grams per day.
0:21:18 > 0:21:22And that's enough to spin 32,000 metres of silk.
0:21:24 > 0:21:28And that's the length of 3,000 football pitches.
0:21:30 > 0:21:34For now, though, they're more interested in Randy's trousers.
0:21:34 > 0:21:38Well, I suppose they're still 99.9% goat after all.
0:21:42 > 0:21:43Spider goats.
0:21:43 > 0:21:46Sounds like science-fiction.
0:21:46 > 0:21:49But if you think that's a weird hybrid, what if I were to
0:21:49 > 0:21:55tell you that someone had actually fused spider silk
0:21:55 > 0:21:57with human skin?
0:21:59 > 0:22:03A lab in the Netherlands took Randy's goat silk
0:22:03 > 0:22:04and created Super Skin.
0:22:08 > 0:22:11Then they shot at it.
0:22:14 > 0:22:16GUNSHOT
0:22:16 > 0:22:19So, why bother going to all the trouble?
0:22:19 > 0:22:20But look!
0:22:20 > 0:22:22The sample isn't destroyed.
0:22:27 > 0:22:30Just look at it stretch as the bullet hits.
0:22:32 > 0:22:35Incredibly, the spider skin holds that bullet firm.
0:22:39 > 0:22:41With the silk strengthening properties, it's
0:22:41 > 0:22:45nearly as tough as Kevlar, the stuff used to make bulletproof vests.
0:22:47 > 0:22:50It's got real potential for an exciting super-fabric.
0:22:52 > 0:22:56Real-life bulletproof spider skin.
0:22:56 > 0:22:57What a thought.
0:22:59 > 0:23:03So, all in all, solar power has serious implications
0:23:03 > 0:23:10for our avian friends, but sun starvation creates sweet sounds...
0:23:10 > 0:23:13especially when teamed up with silky strings.
0:23:14 > 0:23:19And, you know, a spider goat is, in fact, a very real and very useful
0:23:19 > 0:23:26species, whose milk has brought us one step closer to super powers.
0:23:39 > 0:23:41OK, what's coming up next?
0:23:41 > 0:23:48Well, how do you get from simian CPR to spiny star-crossed lovers?
0:23:48 > 0:23:50Let's take a trip to India.
0:23:53 > 0:23:56Kanpur train station.
0:23:57 > 0:24:00The platform bustling with passengers...
0:24:01 > 0:24:05..unaware that they are about to witness a dramatic event...
0:24:07 > 0:24:10..as a body falls onto the tracks.
0:24:15 > 0:24:20A male macaque has been electrocuted crossing live wires overhead
0:24:20 > 0:24:23and there's no sign of life.
0:24:25 > 0:24:28But then, something bizarre happens.
0:24:29 > 0:24:32Another macaque grabs the body.
0:24:39 > 0:24:41Shakes it.
0:24:46 > 0:24:48Pummels it.
0:24:51 > 0:24:52Bites it.
0:24:55 > 0:24:58Even submerges it in water.
0:25:00 > 0:25:03For 20 minutes he keeps up this violent cycle.
0:25:09 > 0:25:11And then...
0:25:11 > 0:25:14to the absolute amazement of the crowd...
0:25:16 > 0:25:19..the macaque begins to come round.
0:25:21 > 0:25:24Now, unsurprisingly, the film went viral.
0:25:24 > 0:25:28Over one million people wanted to watch this monkey CPR.
0:25:34 > 0:25:37It's an incredible piece of footage and really weird, too,
0:25:37 > 0:25:42because we've come to know that some primates can demonstrate
0:25:42 > 0:25:44intelligence, but we don't often think of them
0:25:44 > 0:25:47as being truly sympathetic.
0:25:47 > 0:25:51But you know, these macaques live in strict hierarchies
0:25:51 > 0:25:54and the males will do anything they can to climb up that hierarchy.
0:25:54 > 0:25:56So, here's my question.
0:25:56 > 0:26:00Is this male really administering first aid or is it taking
0:26:00 > 0:26:02advantage of an opportunity?
0:26:02 > 0:26:06An opportunity to kick one of its key competitors when it's down?
0:26:06 > 0:26:08When it's really down?
0:26:10 > 0:26:14Well, amongst the millions of viewers was a macaque specialist.
0:26:14 > 0:26:18Here was this macaque that seemed to be performing CPR on this...
0:26:18 > 0:26:20on his buddy.
0:26:23 > 0:26:25I sent it to my family, I sent it to my friends,
0:26:25 > 0:26:28I sent it to other monkey researchers and said, "Have you seen this?
0:26:28 > 0:26:31"Have you seen what's happening with these animals in India?"
0:26:31 > 0:26:34I knew there had to be more to this story. There had to be a back story.
0:26:37 > 0:26:40Lisa got inside the mind of the macaque.
0:26:42 > 0:26:44Females stay in a troop from birth to death.
0:26:44 > 0:26:47But males, as they reach sexual maturity, actually have to
0:26:47 > 0:26:48migrate out.
0:26:48 > 0:26:50And they do that typically together
0:26:50 > 0:26:52and then they formed kind of these boy bands.
0:26:52 > 0:26:57These male bands that are kind of moving throughout the area in search of another troop to join.
0:26:57 > 0:26:59As I looked at the bigger part of the video,
0:26:59 > 0:27:02the longer video clip, this was clearly almost all males together.
0:27:02 > 0:27:06They could be brothers, they could be siblings of some kind.
0:27:06 > 0:27:08These two animals would have known each other.
0:27:11 > 0:27:15OK. But this is hardly the gentle care of brothers-in-arms.
0:27:15 > 0:27:17The macaque's behaviour is brutal.
0:27:19 > 0:27:21They are not fragile flowers.
0:27:21 > 0:27:25I mean, I like to think the macaques are fairly bombproof.
0:27:25 > 0:27:27If he had wanted to hurt that animal, if he had wanted to kill him,
0:27:27 > 0:27:31there is nothing that would have stopped him.
0:27:31 > 0:27:34It's clear that this animal is committed to getting this
0:27:34 > 0:27:37other monkey back on his feet.
0:27:37 > 0:27:40So, this truly is tough love?
0:27:42 > 0:27:45One friend saving another?
0:27:45 > 0:27:48But how on earth did he know what to do?
0:27:53 > 0:27:56The wires that actually are extended throughout these
0:27:56 > 0:28:00urban areas are a great...they are like highways for macaques, you know?
0:28:00 > 0:28:03They are constantly moving across them.
0:28:03 > 0:28:06A handy shortcut, but pick the wrong wire
0:28:06 > 0:28:08and you're in for a shock.
0:28:09 > 0:28:14Electrocutions are very, very common for monkeys in Southeast Asia.
0:28:16 > 0:28:22Lisa believes that this macaque is no stranger to electrical mishap.
0:28:22 > 0:28:25She thinks he's been in this situation before.
0:28:25 > 0:28:27They've seen animals get electrocuted,
0:28:27 > 0:28:31they've seen them drop, and they know that they've got to go in there
0:28:31 > 0:28:33and kind of do this very vigorous agitation.
0:28:33 > 0:28:38This streetwise macaque has learned from previous experience that
0:28:38 > 0:28:43brute force and perseverance can bring a friend back from the brink.
0:28:43 > 0:28:49His buddy came in there and did what an urban macaque's going to do.
0:28:49 > 0:28:52They're going to...they're going to assess the situation...
0:28:52 > 0:28:55they're going to step in, they've going to change their behaviour.
0:28:55 > 0:28:59They're going to adapt to the situation and he brought his buddy back.
0:28:59 > 0:29:00That's a good monkey.
0:29:02 > 0:29:07What can I say? For once, a happy ending, and we love a happy ending.
0:29:07 > 0:29:09Really bizarre and remarkable too.
0:29:09 > 0:29:13And there must be something about Indian train stations,
0:29:13 > 0:29:15because this isn't the first piece of monkey madness
0:29:15 > 0:29:17to hit the headlines.
0:29:21 > 0:29:27Macaques may be kind to each other, but to us, they can be trouble.
0:29:36 > 0:29:40Yeah, in parts of India, their populations have exploded.
0:29:40 > 0:29:42Particularly in cities,
0:29:42 > 0:29:45where they are making a real nuisance of themselves.
0:29:52 > 0:29:56The station at Lucknow in North India was a favourite
0:29:56 > 0:30:00monkey hang-out until the local authorities brought in a man
0:30:00 > 0:30:04with a unique skillset to tackle these troublemakers.
0:30:14 > 0:30:19Acchan Miyan is Lucknow's official monkey man.
0:30:22 > 0:30:25The monkeys at the station are too used to people to be scared away
0:30:25 > 0:30:30by them...but a man-sized monkey...
0:30:30 > 0:30:33that's a serious threat.
0:30:34 > 0:30:37Monkeys respect hierarchy, they respect authority.
0:30:37 > 0:30:40Those monkeys know that somebody's here who's going to
0:30:40 > 0:30:41kind of lay down the law.
0:30:46 > 0:30:50And it's not the face paint, it's Acchan's acting that really counts.
0:30:50 > 0:30:54It's the way he moves, it's the way he makes eye contact.
0:30:54 > 0:30:57He doesn't even have to have a stick in his hand.
0:30:57 > 0:30:59He can just kind of walk through in a way that every
0:30:59 > 0:31:01monkey's going to be like, "Oh...
0:31:03 > 0:31:04"Maybe we should leave."
0:31:18 > 0:31:21Well, the dressing up might not be entirely necessary,
0:31:21 > 0:31:24but I suppose it demonstrates a certain sense of commitment.
0:31:24 > 0:31:27But on the whole, what a fabulous idea.
0:31:27 > 0:31:30A dominant male on the block means we don't have to take any more
0:31:30 > 0:31:32drastic measures to get rid of those monkeys,
0:31:32 > 0:31:35which is good...and clever, too.
0:31:35 > 0:31:39Although I have to say, I probably can't take recent reports
0:31:39 > 0:31:42of dressing up in Japan quite as seriously.
0:31:47 > 0:31:49Tama Zoo, near Tokyo.
0:31:51 > 0:31:53And that...
0:31:53 > 0:31:56well, that's the head keeper dressed up as a snow leopard.
0:31:56 > 0:31:58DISTANT MEGAPHONE CHATTER
0:31:58 > 0:32:04Why? Well, the zoo staff are taking part in break-out tests...
0:32:06 > 0:32:08..rehearsing procedures should any of their animals
0:32:08 > 0:32:11escaped in the event of an earthquake.
0:32:11 > 0:32:12Oh, look...
0:32:12 > 0:32:14bang!
0:32:14 > 0:32:17There goes the tranquiliser.
0:32:17 > 0:32:19And he's down.
0:32:19 > 0:32:22Method acting at its, er...best.
0:32:25 > 0:32:29Now, this might look like some strange new Japanese game show,
0:32:29 > 0:32:31but actually, this role-play is quite serious.
0:32:40 > 0:32:42In June 2015,
0:32:42 > 0:32:45a major flood set zoo animals loose
0:32:45 > 0:32:47on the streets of Tbilisi, in Georgia.
0:32:51 > 0:32:55Rescue workers managed to save some, but very sadly,
0:32:55 > 0:32:59many animals were lost in the unfortunate aftermath of this event.
0:33:01 > 0:33:03Keeping animals and public safe
0:33:03 > 0:33:06is at the heart of this bizarre yearly escapade.
0:33:08 > 0:33:11And, in fact, it's become so popular with visitors
0:33:11 > 0:33:13that other wildlife parks around the world
0:33:13 > 0:33:15have now been inspired to follow suit.
0:33:35 > 0:33:38OK, I suppose it's a bit of fun and perhaps one day,
0:33:38 > 0:33:41after all of those bizarre rehearsals,
0:33:41 > 0:33:45if there's a real emergency at the zoo, it might all end well.
0:33:47 > 0:33:50But at Israel's Ramat Gan Zoo,
0:33:50 > 0:33:54keeping the residents ON the premises isn't the problem.
0:33:56 > 0:33:59This is Dorit...
0:33:59 > 0:34:02an Indian crested porcupine,
0:34:02 > 0:34:03native to Israel.
0:34:05 > 0:34:10Abandoned as a baby, she's been hand-reared by the staff at the zoo.
0:34:10 > 0:34:13We got really, really attached to her.
0:34:13 > 0:34:16We've known her since she was just a cute little tiny baby.
0:34:18 > 0:34:22They raised her here at the wildlife hospital, so we all got to chip in
0:34:22 > 0:34:25and bottle-feed her and get really, really attached to her,
0:34:25 > 0:34:29and see her grow into this beautiful, beautiful porcupine.
0:34:30 > 0:34:34And for nearly a decade, Dorit's lived a quiet life.
0:34:34 > 0:34:37That was until early 2015,
0:34:37 > 0:34:41when strange sightings started to concern her keepers.
0:34:41 > 0:34:45Like, every morning, I came to the exhibit to see Dorit,
0:34:45 > 0:34:48to feed her, to clean the yard.
0:34:48 > 0:34:52And one special day, I came here and I saw the poop.
0:34:52 > 0:34:56Instead of being inside the exhibit, it was outside.
0:34:56 > 0:35:00And I thought to myself, "One of the keepers was very lazy yesterday.
0:35:00 > 0:35:04"Instead of putting it into the garbage, just swept away.
0:35:04 > 0:35:06"Never mind! I'll clean it up."
0:35:07 > 0:35:10The other keepers denied any slacking,
0:35:10 > 0:35:13but the poo kept appearing.
0:35:13 > 0:35:18I came another day and I saw again the poop was outside of the exhibit.
0:35:23 > 0:35:27Then a couple of weeks later, just as the mysterious poo
0:35:27 > 0:35:31was starting to become a bit of an issue, an alarm went up.
0:35:34 > 0:35:36A call from the primate department came,
0:35:36 > 0:35:39"Your porcupine's out on the loose, we see her, she's right here.
0:35:39 > 0:35:41"She's escaped."
0:35:42 > 0:35:45We rushed to Dorit's enclosure and there she was,
0:35:45 > 0:35:47just being her happy old Dorit self.
0:35:51 > 0:35:56How could Dorit have been in two places at once?
0:35:56 > 0:35:59It was time to get to the bottom of this mystery.
0:36:00 > 0:36:03We decided to put a camera trap, because they're nocturnal,
0:36:03 > 0:36:07they're mostly active at night and we wanted to see what was going on.
0:36:14 > 0:36:16At first, just a few feral cats...
0:36:19 > 0:36:21..a frisky cock...
0:36:24 > 0:36:25But then...
0:36:29 > 0:36:32We realised when we looked at the footage that there is a male
0:36:32 > 0:36:36porcupine that comes in every night for the past month to visit her.
0:36:39 > 0:36:42Dorit wasn't breaking out...
0:36:42 > 0:36:45a wild male was breaking in!
0:36:45 > 0:36:47He's not just defecating next to her,
0:36:47 > 0:36:49he's actually interacting with her through the bars.
0:36:49 > 0:36:52They touch noses, they sniff each other.
0:36:54 > 0:36:56Dorit had a secret lover.
0:36:56 > 0:37:00It's most likely that he smelled her and came all the way into the zoo
0:37:00 > 0:37:03to meet her, which is quite exciting.
0:37:04 > 0:37:08Porcupines, you see, give off a very powerful scent
0:37:08 > 0:37:13that their quills help to stir up and distribute over long distances.
0:37:15 > 0:37:18It's how male and female porcupines find each other
0:37:18 > 0:37:21and then become inseparable for life.
0:37:25 > 0:37:29Dorit's lover was so intoxicated with her aroma that he travelled
0:37:29 > 0:37:33through the Safari Park, past the hippos, past the rhinos
0:37:33 > 0:37:36and the giraffe, just to be by her side.
0:37:38 > 0:37:40The story kind of broke our hearts
0:37:40 > 0:37:43because he found a very special lady but he can't be with her.
0:37:43 > 0:37:46We can't quite release her because we're afraid for her,
0:37:46 > 0:37:48she's imprinted on people.
0:37:48 > 0:37:50We're afraid that she'll come close to people
0:37:50 > 0:37:52and that they'll hurt her.
0:37:52 > 0:37:56We can't bring him in to her because he's a wild porcupine
0:37:56 > 0:37:58and it's unfair to bring him into captivity
0:37:58 > 0:38:00when he belongs out in the wild.
0:38:02 > 0:38:05So the zoo staff are left with only one option...
0:38:05 > 0:38:09to hope that frustration eventually gets the better
0:38:09 > 0:38:11of Dorit's late-night lover.
0:38:14 > 0:38:17So we're hoping for him that he'll give up one day
0:38:17 > 0:38:20and find, you know, another wild porcupine to be with
0:38:20 > 0:38:24and now that we know that Dorit is interested in boys,
0:38:24 > 0:38:29we'll definitely consider bringing her a nice boy porcupine to be with.
0:38:31 > 0:38:36I hope for her to find a nice man also handsome like her.
0:38:45 > 0:38:47Alas, poor Dorit.
0:38:47 > 0:38:49No, don't worry, it's not her.
0:38:49 > 0:38:51Porcupines are one of my favourite animals,
0:38:51 > 0:38:53I wouldn't do that sort of thing.
0:38:53 > 0:38:55But perhaps, you know, this tragedy could end up with a happy ending.
0:38:55 > 0:38:58It could end up as a sort of romantic comedy
0:38:58 > 0:39:00for our spiny star-crossed lovers.
0:39:02 > 0:39:05From a macaque with CPR skills...
0:39:05 > 0:39:07to a monkey man in disguise...
0:39:09 > 0:39:13..bizarre break-out drills and late-night break-ins...
0:39:13 > 0:39:19we've lifted the lid on a weird world of strange secret behaviours.
0:39:32 > 0:39:37Finally, from a man-mole to a congealed colony of deep-sea clones.
0:39:38 > 0:39:40So let's head south...
0:39:40 > 0:39:41Deep South.
0:39:47 > 0:39:53Early morning, deep in the Apalachicola Forest, Florida.
0:39:53 > 0:39:58METALLIC GRUMBLING
0:39:58 > 0:40:01A strange sound breaks the quiet.
0:40:01 > 0:40:03METALLIC GRUMBLING
0:40:03 > 0:40:07Not made by a forest creature,
0:40:07 > 0:40:11but by a man already very hard at work.
0:40:11 > 0:40:14I not only love what I do...
0:40:17 > 0:40:19..I'm bonded to it.
0:40:26 > 0:40:29It's in my blood to do this.
0:40:29 > 0:40:31I don't...
0:40:31 > 0:40:34yearn for any other type of employment.
0:40:39 > 0:40:42METALLIC GRUMBLING
0:40:42 > 0:40:47It's safe to say that Gary doesn't do your average day job.
0:40:47 > 0:40:50There's a technique to it, there's an art to it.
0:40:50 > 0:40:52It's like playing an instrument.
0:40:52 > 0:40:54Either you can play it or you can't.
0:41:00 > 0:41:05Gary makes a unique noise that fellow Floridians in the know
0:41:05 > 0:41:07call a grunt.
0:41:08 > 0:41:11- It's a strange sound... - METALLIC GRUNTING
0:41:11 > 0:41:14..but with an even stranger purpose.
0:41:15 > 0:41:19You see, Gary is a hunter.
0:41:19 > 0:41:23And his grunting brings in the most unexpected catch.
0:41:32 > 0:41:37There's no other technique that I know that can get these
0:41:37 > 0:41:40worms like this, with this right here,
0:41:40 > 0:41:43this simple wooden stump and this piece of iron.
0:41:44 > 0:41:49Earthworms are irresistibly drawn to Gary's grunt.
0:41:49 > 0:41:52He then sells them as bait to fishermen.
0:41:53 > 0:41:56And not just the odd one or two.
0:41:56 > 0:42:01You know, I want to say maybe 3,000 to 4,000 to 5,000 a day
0:42:01 > 0:42:03is a good day.
0:42:03 > 0:42:04That's a lot of worms.
0:42:09 > 0:42:13And there's certainly no arguing that worm grunting works.
0:42:13 > 0:42:15The proof...
0:42:15 > 0:42:18Well, look. It's everywhere.
0:42:20 > 0:42:25But how does it work? Why are worms so drawn to this strange sound?
0:42:30 > 0:42:32Word about Gary's unique skill set
0:42:32 > 0:42:36reached the laboratory of an eminent scientist,
0:42:36 > 0:42:40who was instantly hooked by the worm grunting mystery.
0:42:40 > 0:42:44I'd heard about this technique where you pound a stake into the ground
0:42:44 > 0:42:48and you cause these giant vibrations and this brings up
0:42:48 > 0:42:50thousands of earthworms to the surface.
0:42:53 > 0:42:54That's a real mystery,
0:42:54 > 0:42:57because if you think about it, being on the surface
0:42:57 > 0:42:59of the soil is the last place you want to be if you're an earthworm.
0:42:59 > 0:43:02There's birds and snakes and lizards and ants and all kinds of things
0:43:02 > 0:43:05that can eat you, not to mention you're out in the sun.
0:43:05 > 0:43:07So it's the last place you would ever want to be.
0:43:07 > 0:43:11Why on earth would an earthworm come up out of the ground
0:43:11 > 0:43:13when it senses vibrations?
0:43:13 > 0:43:14There has to be a good reason.
0:43:16 > 0:43:20So Ken went to see the worm grunters in action.
0:43:30 > 0:43:35We got married in 1970 and we've been worming ever since.
0:43:39 > 0:43:41Things are usually not as good as the stories.
0:43:41 > 0:43:43- This was- better- than the stories.
0:43:43 > 0:43:46I mean, up came the earthworms out of the ground.
0:43:46 > 0:43:49Audrey could go around and collect thousands of them.
0:43:49 > 0:43:52It was just really something to see and they're huge earthworms,
0:43:52 > 0:43:53so it's really dramatic.
0:43:56 > 0:44:00Now, we all know that worms prefer to live below the surface.
0:44:00 > 0:44:03And that there is one circumstance when they tend to pop up
0:44:03 > 0:44:05and that is when it's raining.
0:44:05 > 0:44:09So Ken had a theory which he thought could solve
0:44:09 > 0:44:12this worm grunting mystery once and for all...
0:44:12 > 0:44:15that Gary's vibrations were replicating
0:44:15 > 0:44:19the pitter-patter of rain, right?
0:44:19 > 0:44:21Well...actually...no.
0:44:29 > 0:44:31Earthworms come to the surface after a long rain,
0:44:31 > 0:44:37but it usually takes a whole day of rain or at least hours of rain.
0:44:37 > 0:44:41You don't see earthworms fleeing to the surface at the first raindrops.
0:44:41 > 0:44:45Ken had a hunch that something much more dramatic was causing
0:44:45 > 0:44:49this behaviour and that hunch was that so many worms
0:44:49 > 0:44:53would only surface so quickly if they were running scared.
0:44:55 > 0:44:59If you're chasing your dinner, you don't want to risk your life.
0:44:59 > 0:45:01But if you're about to be dinner,
0:45:01 > 0:45:04you need to risk your life to escape.
0:45:04 > 0:45:06And his suspicions were confirmed
0:45:06 > 0:45:09with the help of an old friend.
0:45:09 > 0:45:12Darwin says that it has often been reported,
0:45:12 > 0:45:15when the ground is beaten or made to tremble, that worms believe
0:45:15 > 0:45:20they're pursued by a mole and will exit their burrows to the surface.
0:45:21 > 0:45:25Yes, Ken thought the vibration of Gary's grunting
0:45:25 > 0:45:29was mimicking the tunnelling of the worms' ultimate predator.
0:45:30 > 0:45:32He just had to prove it.
0:45:32 > 0:45:35Gary had a bucket of worms,
0:45:35 > 0:45:39and I had collected a mole, and we sort of looked at each other
0:45:39 > 0:45:42and thought, "well, let's just do this."
0:45:48 > 0:45:50Up came the worms, streaming out to the surface,
0:45:50 > 0:45:53and that was just great because the two of us sort of together,
0:45:53 > 0:45:56Gary and I, looking into this bucket,
0:45:56 > 0:45:59sort of looked at each other and thought, "it's probably moles."
0:46:02 > 0:46:08Without knowing it, worm grunters are perfect mole impersonators.
0:46:08 > 0:46:11The sound that the worm grunters are making is like
0:46:11 > 0:46:14the giant mother of all moles.
0:46:14 > 0:46:19To an earthworm, that's a terrifying sound.
0:46:19 > 0:46:23That's what he told me. He said, "You're a giant mole."
0:46:23 > 0:46:25I said, "That works for me."
0:46:25 > 0:46:28What a thing! Worm grunter and biologist
0:46:28 > 0:46:32coming together to solve the weirdest-sounding mystery out there.
0:46:32 > 0:46:35It doesn't get more perfect.
0:46:37 > 0:46:41Grunting sends earthworms fleeing to the surface.
0:46:41 > 0:46:44But, you know, there was another subterranean creature
0:46:44 > 0:46:47found in North Carolina that the residents
0:46:47 > 0:46:49clearly wished had remained underground.
0:46:52 > 0:46:55The city of Raleigh.
0:46:55 > 0:46:57Leafy,
0:46:57 > 0:46:59quiet,
0:46:59 > 0:47:00safe.
0:47:00 > 0:47:04Well, until the spring of 2009
0:47:04 > 0:47:05when all that changed.
0:47:08 > 0:47:12We're a mid-size government town. A lot of beige architecture.
0:47:12 > 0:47:15Don't get a lot of, uh, monsters.
0:47:19 > 0:47:23Like every city, below the roads and pavements is a network of sewers.
0:47:27 > 0:47:31And like in every city, they need inspecting.
0:47:32 > 0:47:35We have to monitor the condition of the pipes on a frequent basis
0:47:35 > 0:47:37because they can get blocked.
0:47:42 > 0:47:44Strange things you'll see are snakes,
0:47:44 > 0:47:47money, there's jewellery.
0:47:47 > 0:47:49And we certainly see our fair share of rats.
0:47:52 > 0:47:56But on April 27th, the cameras captured something,
0:47:56 > 0:47:58the likes of which this city had never seen.
0:48:01 > 0:48:04So, it appeared that they were going down either a six or eight inch pipe,
0:48:04 > 0:48:08with this...with the robot, and they came across a...
0:48:08 > 0:48:12..really unusual, somewhat animated...
0:48:13 > 0:48:15..um, slimy...substance.
0:48:23 > 0:48:26The feed from the cameras showed a bizarre clump
0:48:26 > 0:48:30of a strange and unidentified substance.
0:48:30 > 0:48:32Slimy and smooth,
0:48:32 > 0:48:34reacting to the robot's light.
0:48:34 > 0:48:37Pulsating and morphing.
0:48:37 > 0:48:40I was at a loss for an explanation.
0:48:42 > 0:48:44It was, um, really something
0:48:44 > 0:48:47that I've seen out of a science fiction movie.
0:48:49 > 0:48:53The discovery of something strange lurking in the sewers didn't
0:48:53 > 0:48:56stay secret for long.
0:48:56 > 0:48:59There was a clamour, you know. A great alarm in the streets.
0:48:59 > 0:49:03It was as though Godzilla had shown up. We were all extremely excited
0:49:03 > 0:49:06and, of course, dashed right out to find out about it.
0:49:07 > 0:49:11The sewer blob became a sensation.
0:49:11 > 0:49:14Everyone had their own theory.
0:49:19 > 0:49:21SCREAMING
0:49:24 > 0:49:26There was a movie called The Blob,
0:49:26 > 0:49:28and so everyone was making a lot of Blob references.
0:49:28 > 0:49:30There were...
0:49:30 > 0:49:33People thought that it was pudding come to life.
0:49:33 > 0:49:35People thought that it was radioactive.
0:49:35 > 0:49:37We were getting a lot of questions
0:49:37 > 0:49:39and, unfortunately, we didn't have any good answers.
0:49:39 > 0:49:41Maybe it was an experiment gone wrong.
0:49:41 > 0:49:46Maybe something slithered out of a test-tube and into the sewer system.
0:49:46 > 0:49:50If only. But what was the truth behind the headline?
0:49:54 > 0:49:57Fingers pointed towards these.
0:49:57 > 0:49:59Bryozoa.
0:49:59 > 0:50:02Thousands of tiny aquatic animals that live together,
0:50:02 > 0:50:05clustered along the bottom of ships and docks.
0:50:06 > 0:50:09But this theory didn't quite add up.
0:50:09 > 0:50:13Most Bryozoans live in the ocean and actually have these hard little
0:50:13 > 0:50:16coffin-like boxes that each Bryozoan body is in.
0:50:19 > 0:50:22When there's a lot of them in one place, they can look like a big fleshy blob.
0:50:22 > 0:50:26However, this blob was a bit too big
0:50:26 > 0:50:30and not quite the right colour to be freshwater Bryozoans.
0:50:32 > 0:50:34So, what was this pulsating mass?
0:50:36 > 0:50:39Could there really be a sensible scientific explanation?
0:50:42 > 0:50:44These are worms, annelid worms -
0:50:44 > 0:50:47actually, close relatives of earthworms.
0:50:47 > 0:50:51It's actually not quite known how many species,
0:50:51 > 0:50:54but they're loosely called tubifex.
0:50:56 > 0:50:59Tubifex worms live in the water,
0:50:59 > 0:51:01anchoring themselves against the current
0:51:01 > 0:51:03and grabbing food as it passes.
0:51:08 > 0:51:12Tubifex, in the wild, typically lives in stagnant water.
0:51:12 > 0:51:15They can handle quite low oxygen.
0:51:15 > 0:51:18They have this deep red blood that gives them their colour.
0:51:18 > 0:51:22It allows them to absorb the oxygen through their thin skin.
0:51:24 > 0:51:27The prime real estate for something like a tubifex is somewhere
0:51:27 > 0:51:31where you can attach to the bottom firmly, and there's food going by.
0:51:31 > 0:51:34Obviously, a sewer wouldn't be our first choice for a home,
0:51:34 > 0:51:36but for a tubifex, it's absolutely perfect.
0:51:38 > 0:51:41That many resources in one place, you can get really dense clumps of them.
0:51:44 > 0:51:49So, not a single monster at all, but a colony that moves like one.
0:51:51 > 0:51:55Each worm can sense movement around it and it can also contract,
0:51:55 > 0:51:58so that's almost like a chain of dominoes.
0:51:58 > 0:52:02- This town is in danger. - 'How can it be stopped?'
0:52:02 > 0:52:05I think people are generally weirded out by whatever
0:52:05 > 0:52:09lives in the sewer, and if it's a giant, shiny, slimy,
0:52:09 > 0:52:14pulsing ball of worms, then I can understand why they'd be grossed out.
0:52:15 > 0:52:20There could be tubifex in a sewer right under your feet right now.
0:52:20 > 0:52:24That might be a horrifying thought - unless, of course, you're Josh.
0:52:24 > 0:52:28I think that the sewer monster would make an excellent mascot.
0:52:28 > 0:52:31I don't know why anyone didn't print T-shirts.
0:52:38 > 0:52:42OK, I know a ball of tubifex doesn't exactly constitute a monster,
0:52:42 > 0:52:44but it is pretty revolting.
0:52:44 > 0:52:47But then, I suppose, if you're a worm living down a sewer,
0:52:47 > 0:52:50you don't really have to care too much about your looks.
0:52:50 > 0:52:54But that's not to say that all colonial animals are horrid.
0:52:54 > 0:52:57Some of them are exquisitely beautiful.
0:53:03 > 0:53:05Deep below the surface,
0:53:05 > 0:53:10a group of scientists are surveying the ocean floor...
0:53:10 > 0:53:14when they spot something unusual.
0:53:14 > 0:53:15What the...?
0:53:16 > 0:53:18- Oh, it's...- Oh.
0:53:20 > 0:53:22Garbage?
0:53:23 > 0:53:24My goodness.
0:53:26 > 0:53:29Their remote camera picks up a bizarre object
0:53:29 > 0:53:31moving in the current.
0:53:33 > 0:53:36- Oh, my gosh!- I can't believe that's a living thing.
0:53:36 > 0:53:39That's amazing. Oh, how cool.
0:53:39 > 0:53:40What?
0:53:42 > 0:53:45Spotting this strange sea creature has made these
0:53:45 > 0:53:48seasoned scientists a little bit giddy.
0:53:48 > 0:53:49What is this?
0:53:49 > 0:53:51I guess siphonophore?
0:53:53 > 0:53:55Yup. Wow.
0:53:59 > 0:54:03You've probably never heard of a siphonophore.
0:54:03 > 0:54:06But Dr Dunn understands their excitement.
0:54:06 > 0:54:09I remember the first time I saw a siphonophore
0:54:09 > 0:54:11live in the water.
0:54:11 > 0:54:14They look like swimming glass chandeliers.
0:54:14 > 0:54:17They look like nothing else.
0:54:17 > 0:54:21It's as if, all of a sudden, there's this whole new life form
0:54:21 > 0:54:24that you've never heard of, right in front of you.
0:54:25 > 0:54:28But what is this beautifully bizarre animal?
0:54:30 > 0:54:34A siphonophore is a cnidarian, so it's a relative of corals
0:54:34 > 0:54:38and many of the jellyfish that people are familiar with.
0:54:40 > 0:54:43Siphonophores live in the open ocean,
0:54:43 > 0:54:47forming the most intricate shapes in astonishing colours.
0:54:51 > 0:54:54They look like glass sculptures. They're absolutely beautiful.
0:54:54 > 0:54:57They really look like something from another world.
0:54:59 > 0:55:02And what might really surprise you is that these
0:55:02 > 0:55:05spectacular sea creatures aren't rare.
0:55:07 > 0:55:10Siphonophores are the largest,
0:55:10 > 0:55:14most abundant organisms that most people have never heard of.
0:55:18 > 0:55:20Most people haven't seen a siphonophore,
0:55:20 > 0:55:23because they're so fragile that they're destroyed before they get
0:55:23 > 0:55:26close to the coast. They're just turned over in the waves.
0:55:26 > 0:55:29They can't handle the sediment in the water.
0:55:30 > 0:55:35Siphonophores are undeniably exquisitely beautiful creatures,
0:55:35 > 0:55:39but that's not why Casey has given up so much time to study them.
0:55:39 > 0:55:43No, it's because they are one of the weirdest animals
0:55:43 > 0:55:45living in our ocean.
0:55:45 > 0:55:51You see, the thing is, strictly speaking, they're not one animal.
0:55:51 > 0:55:54When we're born, we have one cute little baby body,
0:55:54 > 0:55:57and then that baby body has all the parts of the adult
0:55:57 > 0:56:01but they just get bigger as we enlarge.
0:56:01 > 0:56:04A siphonophore grows in a completely different way.
0:56:07 > 0:56:10What they do is they're born as one little baby body,
0:56:10 > 0:56:13and then instead of that baby body growing,
0:56:13 > 0:56:17that baby body just makes more baby bodies.
0:56:17 > 0:56:19Each of them are specialised for particular tasks.
0:56:19 > 0:56:22Some bodies are specialised for tasks like feeding.
0:56:22 > 0:56:25Others are specialised for tasks like swimming.
0:56:25 > 0:56:28And this growth continues in a conveyor-like fashion
0:56:28 > 0:56:31through the life of the siphonophore.
0:56:31 > 0:56:34So, if we grew like a siphonophore,
0:56:34 > 0:56:37we'd start life as a baby,
0:56:37 > 0:56:39but rather than growing bigger,
0:56:39 > 0:56:43this baby would grow more babies out of its side.
0:56:43 > 0:56:46Some of these babies would only be able to eat
0:56:46 > 0:56:49because they'd only have a mouth.
0:56:49 > 0:56:53Other babies would only be able to walk because they just had legs.
0:56:53 > 0:56:59But together, these connected babies could satisfy all the tasks
0:56:59 > 0:57:02needed for a human to survive.
0:57:04 > 0:57:08OK, so what's the biggest thing swimming in the ocean?
0:57:08 > 0:57:10It's the blue whale, of course.
0:57:10 > 0:57:14But you know the bizarre growth form of those siphonophores
0:57:14 > 0:57:16means that the longest of them
0:57:16 > 0:57:19can stretch out to more than 40 metres,
0:57:19 > 0:57:22which is ten metres longer than the biggest blue whale.
0:57:27 > 0:57:31So, worms are terrified of moles...
0:57:31 > 0:57:33and Gary.
0:57:33 > 0:57:36And if you want to scare the residents of Raleigh,
0:57:36 > 0:57:38group together in sewers.
0:57:38 > 0:57:41It was a little frightening.
0:57:41 > 0:57:45But in the deep ocean, a colony can create a creature unique enough
0:57:45 > 0:57:49to excite the most serious of scientific brains.
0:57:49 > 0:57:51- Oh, gosh!- Awesome!
0:57:53 > 0:57:56It's a weird, weird world.
0:57:57 > 0:58:01And it's only going to get weirder.
0:58:01 > 0:58:04Next time, what's caused this shadow in the sea?
0:58:04 > 0:58:07Immediately, we thought it was an oil slick.
0:58:07 > 0:58:08What else could it have been?
0:58:08 > 0:58:11And why is this lemming so angry?
0:58:13 > 0:58:14Why do dogs spin?
0:58:15 > 0:58:18And can you really use your ears to see?
0:58:18 > 0:58:24I am a man who uses the techniques of a bat to navigate.
0:58:24 > 0:58:27How do you explain these bizarre circles?
0:58:27 > 0:58:30And how do you get gold from poo?