0:00:17 > 0:00:22In this episode, we'll discover why goats might fly,
0:00:22 > 0:00:25encounter some ghostly figures in the clouds
0:00:25 > 0:00:30and find out why albatross chicks are being planted in flowerpots.
0:00:33 > 0:00:37But first, let's meet some of the world's weirdest weaponised wonders.
0:00:42 > 0:00:44Bondi Beach, Australia.
0:00:45 > 0:00:50People come here to surf, to sunbathe and to be seen.
0:00:51 > 0:00:53But in April 2015,
0:00:53 > 0:00:58this seaside sanctuary was to become the scene of a coastal crisis.
0:00:59 > 0:01:02So I ended up having trouble breathing
0:01:02 > 0:01:05and I started to get chest pains.
0:01:05 > 0:01:08I've never felt anything like that before.
0:01:14 > 0:01:15HORN BLARES
0:01:15 > 0:01:18Surf life-saver Rosie Tailano
0:01:18 > 0:01:21was taking part in the weekly biathlon.
0:01:23 > 0:01:25I did my first leg of the swim
0:01:25 > 0:01:29and all was normal, all was perfectly fine.
0:01:29 > 0:01:33But as she raced towards the finish line,
0:01:33 > 0:01:36something was waiting beneath the waves.
0:01:37 > 0:01:40I felt an initial sting on my chest,
0:01:40 > 0:01:43but I went to get it out of my costume and nothing was there.
0:01:45 > 0:01:47It was very frightening.
0:01:50 > 0:01:53But despite the excruciating pain, she struggled on.
0:01:54 > 0:01:58So, it wasn't until I got home that the symptoms began worsening
0:01:58 > 0:02:02and I began to get chest pain, the rash began developing,
0:02:02 > 0:02:04and I had trouble breathing.
0:02:04 > 0:02:08In minutes, Rosie was gasping for air.
0:02:08 > 0:02:09She was rushed to hospital.
0:02:10 > 0:02:13Thankfully, the doctors stabilised her condition.
0:02:13 > 0:02:15But what had stung her?
0:02:18 > 0:02:20What was this aquatic assailant?
0:02:22 > 0:02:27Well, in Australian waters, there's no shortage of potential culprits.
0:02:27 > 0:02:31On the sea floor, anemones and sea urchins cling to rocks,
0:02:31 > 0:02:34some armed with a paralysing neurotoxin.
0:02:36 > 0:02:40Hiding in the sands lurks the world's most dangerous fish,
0:02:40 > 0:02:42the stonefish,
0:02:42 > 0:02:46spines laden with a potent mix of toxins
0:02:46 > 0:02:48that could kill a human within an hour.
0:02:50 > 0:02:54Scuttling along the sea floor, the blue-ringed octopus
0:02:54 > 0:02:57is one of the most dangerous animals in the ocean,
0:02:57 > 0:03:01its venom over a thousand times more deadly than cyanide.
0:03:04 > 0:03:07And sea snakes regularly come to the water's surface,
0:03:07 > 0:03:10the scene of this crime.
0:03:10 > 0:03:14But could their fangs really have punctured through Rosie's costume?
0:03:21 > 0:03:25Well, Rosie had a theory of her own.
0:03:25 > 0:03:27Originally, I thought it was just a bluebottle,
0:03:27 > 0:03:32but there were no warnings that day of any stingers in the ocean.
0:03:32 > 0:03:33These infamous jellies,
0:03:33 > 0:03:36the Portuguese Man o' War, or bluebottles,
0:03:36 > 0:03:40as they're known in Australia, can float in shoals of up to 1,000,
0:03:40 > 0:03:43causing carnage when they come close to the shore.
0:03:45 > 0:03:49Responsible for more recorded stings than any other species,
0:03:49 > 0:03:52they inflict painful streaks when their tentacles,
0:03:52 > 0:03:54sometimes up to 50 metres long,
0:03:54 > 0:03:57wrap themselves around unsuspecting swimmers.
0:03:58 > 0:04:02But for Rosie, the evidence just didn't stack up.
0:04:02 > 0:04:04With a bluebottle sting,
0:04:04 > 0:04:09the rash usually is a welt size with white appearance,
0:04:09 > 0:04:12but with this, it was a very dotty, red rash,
0:04:12 > 0:04:15quite different from the bluebottle.
0:04:20 > 0:04:24So, with all the usual suspects ruled out,
0:04:24 > 0:04:27the source of Rosie's sting was still a mystery,
0:04:27 > 0:04:31but what could've caused her quite so much agony?
0:04:33 > 0:04:35Well, at about the same time...
0:04:38 > 0:04:41..some very strange videos started turning up on the internet.
0:04:43 > 0:04:45Yes, just two months earlier,
0:04:45 > 0:04:48this bizarre creature was washed up on the beach
0:04:48 > 0:04:51just a few hundred kilometres to the north.
0:04:51 > 0:04:54And this one had been found near Brisbane.
0:05:04 > 0:05:07Millions of people watched these videos online,
0:05:07 > 0:05:10all asking the same question -
0:05:10 > 0:05:11what on earth are they?
0:05:15 > 0:05:16These animals are so weird
0:05:16 > 0:05:20that people didn't really know what to make out of them.
0:05:22 > 0:05:24They are so weird-looking
0:05:24 > 0:05:27and they almost look like they are alien organisms.
0:05:27 > 0:05:30Somebody proposed that they were insects,
0:05:30 > 0:05:33somebody else proposed that they were juvenile sharks,
0:05:33 > 0:05:35and it wasn't until much more recently
0:05:35 > 0:05:39people realised that they were molluscs and they were sea slugs.
0:05:41 > 0:05:45Yes, these tiny animals are blue sea dragons,
0:05:45 > 0:05:48a kind of nudibranch, or sea slug.
0:05:52 > 0:05:54They come from a truly bizarre family
0:05:54 > 0:05:57of brightly-coloured marine gastropods.
0:06:00 > 0:06:03Most of them live on the bottom of the ocean,
0:06:03 > 0:06:07grazing on anything, from corals to anemones and even other sea slugs.
0:06:10 > 0:06:15But the blue sea dragon dines on something entirely different.
0:06:15 > 0:06:18Blue sea dragons feed primarily on the Portuguese Man o' War,
0:06:18 > 0:06:21which is one of the most venomous organisms in the water.
0:06:21 > 0:06:23What they can do is they can steal
0:06:23 > 0:06:26that defensive mechanism that the Man o' War has
0:06:26 > 0:06:29and utilise them for their own defence.
0:06:29 > 0:06:32The blue sea dragon lives at the ocean's surface,
0:06:32 > 0:06:35which puts it at the scene of the crime,
0:06:35 > 0:06:37and it has the right weapon, too.
0:06:39 > 0:06:44You see, it does something few other animals would dare,
0:06:44 > 0:06:45it eats its fill
0:06:45 > 0:06:48of the fearsome Man o' War,
0:06:48 > 0:06:50but instead of getting stung,
0:06:50 > 0:06:52it does something incredible.
0:06:52 > 0:06:54It absorbs the paralysing
0:06:54 > 0:06:56stinging cells, the nematocyst,
0:06:56 > 0:06:58and concentrates the toxin.
0:06:59 > 0:07:02Then it uses it for its own defences,
0:07:02 > 0:07:06making it a very dangerous delicacy for any predator.
0:07:06 > 0:07:09Or, of course, anyone who gets in the way.
0:07:11 > 0:07:13WOMAN SCREAMS
0:07:15 > 0:07:17When people encounter blue sea dragons,
0:07:17 > 0:07:20they're going to be finding them on the beach, typically.
0:07:20 > 0:07:24By then, the animals are probably no longer venomous.
0:07:24 > 0:07:27Now, if people were to encounter blue sea dragons in the open ocean,
0:07:27 > 0:07:30that would be a different story, because that's where the animals
0:07:30 > 0:07:33are basically charged and I would be very careful not to touch them.
0:07:34 > 0:07:37To activate its deadly defence,
0:07:37 > 0:07:39the blue sea dragon squeezes its muscles,
0:07:39 > 0:07:44pushing out the stolen stinging cells, which detonate,
0:07:44 > 0:07:48shocking a predator, or an unsuspecting swimmer.
0:07:50 > 0:07:52Yeah, I was actually really surprised
0:07:52 > 0:07:56that something so small and beautiful could cause so much pain.
0:08:05 > 0:08:11So, the ingenious blue sea dragon doesn't produce its own venom.
0:08:11 > 0:08:14Just like any good comic book villain, it steals it.
0:08:14 > 0:08:17And then of course, it was simply a case of wrong place,
0:08:17 > 0:08:19wrong time for Rosie.
0:08:19 > 0:08:21Mystery solved.
0:08:21 > 0:08:22But there's some good news, too.
0:08:22 > 0:08:23After just a couple of days,
0:08:23 > 0:08:26she was fully recovered and back in the water.
0:08:31 > 0:08:34We're winging our way to the USA.
0:08:37 > 0:08:40The Rocky Mountains, Utah.
0:08:40 > 0:08:46Home to a unique species, Oreamnos americanus,
0:08:46 > 0:08:47the American Mountain goat.
0:08:47 > 0:08:49One of the world's best climbers.
0:08:49 > 0:08:53Known for their abilities to scale incredible peaks and pick their way
0:08:53 > 0:08:55along dangerous precipices.
0:09:01 > 0:09:07But in 2015, these adrenaline junkies took their extreme lifestyle
0:09:07 > 0:09:08one step further.
0:09:08 > 0:09:11Yes, they're flying, but why?
0:09:13 > 0:09:17Well, in Willard Peak, the population has grown out of control
0:09:17 > 0:09:20and is overgrazing this fragile habitat.
0:09:22 > 0:09:24So, in Utah, we don't really have any natural predators
0:09:24 > 0:09:25for mountain goats.
0:09:28 > 0:09:31If the number of mountain goats gets too high in Willard Peak,
0:09:31 > 0:09:34we could start seeing them causing damage
0:09:34 > 0:09:35to the surrounding vegetation.
0:09:35 > 0:09:39So, we're trying to be proactive by taking goats off of there before
0:09:39 > 0:09:42they get too numerous and too dense.
0:09:42 > 0:09:45Kent needed to find a way to bring the numbers down,
0:09:45 > 0:09:49and with populations struggling in other areas, relocating them
0:09:49 > 0:09:51was the perfect solution.
0:09:53 > 0:09:56But first, he had to catch them.
0:09:58 > 0:10:00Something that's easier said than done.
0:10:04 > 0:10:09Mountain goats are 130kg of pure muscle.
0:10:09 > 0:10:12And they're not just powerful, they're nimble too.
0:10:12 > 0:10:16Able to jump over 3.5 metres in a single bound.
0:10:20 > 0:10:21So, Kent's solution?
0:10:21 > 0:10:25A crack team of relocation experts.
0:10:25 > 0:10:30An aerial A-Team, armed with high-powered pneumatic net guns.
0:10:33 > 0:10:37But even with these hi-tech solutions, success isn't guaranteed.
0:10:39 > 0:10:42So, mountain goats live in very steep, cliffy areas
0:10:42 > 0:10:44and so it's very difficult to catch them
0:10:44 > 0:10:46because if you were to shoot a net on them
0:10:46 > 0:10:49in the middle of a cliff, they would likely tumble down
0:10:49 > 0:10:52and likely injure themselves or possibly be killed.
0:10:52 > 0:10:56And so it's very important to make sure you use the helicopter
0:10:56 > 0:10:59and you gently push them into a relatively flat area where you can
0:10:59 > 0:11:00successfully put a net on them
0:11:00 > 0:11:03and they won't tumble down the side of the mountain.
0:11:04 > 0:11:05Bull's-eye.
0:11:10 > 0:11:14Now, it's all about speed and keeping stress to a minimum.
0:11:18 > 0:11:20So, to limit the stress on the animals,
0:11:20 > 0:11:22we put a blindfold on them so that they can't see.
0:11:22 > 0:11:26When we take away that visual sensation, it calms the animals down
0:11:26 > 0:11:28a lot and helps to make them relax quite a bit.
0:11:40 > 0:11:44By targeting the female goats, Kent and his team maximise
0:11:44 > 0:11:47the reproductive potential of the new population.
0:11:47 > 0:11:51After a few quick tests, they're driven to their
0:11:51 > 0:11:55snowy new home - Mount Dutton, a veritable goat utopia
0:11:55 > 0:11:58of unexplored peaks, 400km to the south.
0:12:01 > 0:12:02And the final result?
0:12:04 > 0:12:08So, when you look 10, 20 years into the future and you see that
0:12:08 > 0:12:12a population that you helped transplant is established
0:12:12 > 0:12:15and doing well and other people can enjoy it, it's a great feeling.
0:12:18 > 0:12:20Is it a bird? Is it a plane?
0:12:20 > 0:12:23No, it's a flying goat.
0:12:23 > 0:12:26Obviously, the best way to redistribute
0:12:26 > 0:12:27this important population.
0:12:27 > 0:12:30But I've got to tell you, that Kent and his team are not pioneers
0:12:30 > 0:12:34when it comes to this extreme animal relocation.
0:12:34 > 0:12:37Animals have been flying into new homes for years.
0:12:38 > 0:12:41Just ask Idaho's beavers.
0:12:42 > 0:12:45'20 beaver ready for the flight to Mountain Meadows.'
0:12:46 > 0:12:51Yes, back in the 1950s, the Idaho authorities wanted to save
0:12:51 > 0:12:55themselves the cost of building a dam, so they decided to enlist
0:12:55 > 0:13:00beavers to do it for them and they parachuted them in.
0:13:01 > 0:13:03That's a bit of a bumpy landing.
0:13:03 > 0:13:07'And a most unusual and novel trip ends for Mr Beaver.'
0:13:07 > 0:13:10Look, look. He's OK. He's out. He's living.
0:13:10 > 0:13:14That is one bemused beaver.
0:13:14 > 0:13:17But thankfully, Kent and his helicoptering goats are proving
0:13:17 > 0:13:21that delivery methods have improved a little bit since the early days.
0:13:25 > 0:13:28From flying goats and parachuting beavers
0:13:28 > 0:13:31to a different kind of rescue mission entirely.
0:13:37 > 0:13:40700km from the coast of New Zealand is
0:13:40 > 0:13:44a strange volcanic island - the Pyramid.
0:13:44 > 0:13:48The most important place on the planet for an entire species.
0:13:50 > 0:13:51The Chatham albatross.
0:13:53 > 0:13:58The Chatham albatross is only found in the Chathams and there, even,
0:13:58 > 0:14:03it only breeds on one small rock stack.
0:14:05 > 0:14:09It literally is a pile of rocks coming out of the sea.
0:14:11 > 0:14:14But the species is under attack.
0:14:14 > 0:14:16Its very survival is in doubt.
0:14:18 > 0:14:22Unlike the other albatross species, the threat isn't from
0:14:22 > 0:14:25commercial fishing, nor is it disease
0:14:25 > 0:14:28or a rampaging rogue predator.
0:14:31 > 0:14:35No, the problem for the Chatham albatross is elemental.
0:14:39 > 0:14:42One of the biggest threats to Chatham albatross, actually,
0:14:42 > 0:14:43is climate change.
0:14:45 > 0:14:50The Chathams are lashed by storms all the time.
0:14:50 > 0:14:53So the islands and the species are adapted to that, but when the storms
0:14:53 > 0:14:56come from an easterly direction, that's what causes the havoc.
0:15:01 > 0:15:05This wonderful papier mache model represents the pyramid, and for
0:15:05 > 0:15:08thousands of years, the albatross have been nesting
0:15:08 > 0:15:13on the north-east side, protected from the prevailing winds.
0:15:13 > 0:15:18The thing is, the soil here, which they make their nest from,
0:15:18 > 0:15:23is very soft and easily eroded, and things are changing.
0:15:23 > 0:15:27Due to climate change, there's been an increase in the frequency
0:15:27 > 0:15:29and the severity of the winds.
0:15:29 > 0:15:30And the result...
0:15:32 > 0:15:35LOUDER: ..is that all of that soil is blowing away,
0:15:35 > 0:15:38making it impossible for the birds to nest here.
0:15:38 > 0:15:40So what can be done to save them?
0:15:44 > 0:15:46Well, move them from the island.
0:15:46 > 0:15:49Surely that would be the obvious solution?
0:15:49 > 0:15:52Yeah. But the thing with albatross, you see,
0:15:52 > 0:15:55is that they have a superpower and it's working against them.
0:15:58 > 0:16:03When the young albatross fledge their nest, they wander widely
0:16:03 > 0:16:07over the southern Pacific Ocean and they continue to do
0:16:07 > 0:16:11that for a number of years until they reach sexual maturity.
0:16:11 > 0:16:16Then, a homing instinct kicks in and they head back to the island where
0:16:16 > 0:16:19they grew up. And, do you know, sometimes, when they first land
0:16:19 > 0:16:23on it, they will land only a matter of metres away from the nest
0:16:23 > 0:16:25that they actually grew up in.
0:16:28 > 0:16:32So move an albatross and it'll come right back to its nest,
0:16:32 > 0:16:36a perfectly designed mound of insulating mud and vegetation,
0:16:36 > 0:16:39home for the chicks' first five months.
0:16:42 > 0:16:46So how do you undo thousands of years of evolution?
0:16:47 > 0:16:51Well, Mike and his team had a plan.
0:16:51 > 0:16:56In January 2014, they set about saving the Chatham albatross,
0:16:56 > 0:17:02moving them to a new safe island, 50km to the north.
0:17:02 > 0:17:05And for the plan to work, they had to target the chicks.
0:17:05 > 0:17:09The adults' natural compass was too well engrained.
0:17:09 > 0:17:12The Pyramid would always be their home.
0:17:12 > 0:17:1699.9% of sea birds will come back to the island they were raised from.
0:17:16 > 0:17:21So we're taking these chicks and trying to establish a new colony.
0:17:22 > 0:17:25They chose only the healthiest youngsters,
0:17:25 > 0:17:28the ones old enough to cope with the separation from their parents
0:17:28 > 0:17:31but young enough to accept a new island.
0:17:33 > 0:17:36We're basically hoping that we can reprogramme their GPS
0:17:36 > 0:17:40so that they'll fly back to the main island rather than the pyramid.
0:17:41 > 0:17:47With the plan hinged on persuading the chicks to accept their new home,
0:17:47 > 0:17:50Mike needed to perfectly copy the colony
0:17:50 > 0:17:53and, most importantly, the nests.
0:17:57 > 0:18:01And his solution? Well, it was beautifully basic.
0:18:06 > 0:18:09For an albatross chick, its nest is its castle.
0:18:09 > 0:18:12It's parents know to come back to that nest,
0:18:12 > 0:18:15that's where it'll find its chick and that's where it'll be fed.
0:18:15 > 0:18:18So it's engrained in these chicks to stay on their nest until they leave,
0:18:18 > 0:18:22so we had to find something to replicate that nest.
0:18:22 > 0:18:27And who would've thought a flowerpot was the ideal replacement?
0:18:27 > 0:18:28Filled with rocks and peat,
0:18:28 > 0:18:32it provided not only a comfy seat but fantastic drainage too.
0:18:34 > 0:18:38But making the ultimate albatross nursery didn't stop there.
0:18:38 > 0:18:41Mike needed to make the chicks feel safe,
0:18:41 > 0:18:44so he's provided plastic bodyguards...
0:18:46 > 0:18:49..enlisted the help of the local community
0:18:49 > 0:18:54to become surrogate parents, delivering daily meals,
0:18:54 > 0:18:58and he's even playing mood music on hidden speakers.
0:18:58 > 0:19:02And if he's successful, for the first time,
0:19:02 > 0:19:07the Chatham albatross won't have all of its eggs in one basket.
0:19:07 > 0:19:12With two colonies on two islands, Mike hopes the species will survive,
0:19:12 > 0:19:15no matter what climate change throws at it.
0:19:16 > 0:19:20This project's going to have several different measures of success.
0:19:20 > 0:19:24The first one will be when the first birds return and breed.
0:19:24 > 0:19:28So, for us, it'll be when we've got a core of birds that are starting
0:19:28 > 0:19:32to breed and that's starting to grow to be a new colony.
0:19:32 > 0:19:35But our overall aim is to try and future-proof
0:19:35 > 0:19:38Chatham island albatross in a changing world.
0:19:40 > 0:19:42It'll be at least three more years
0:19:42 > 0:19:45before they know if they've been successful.
0:19:45 > 0:19:49So it's all fingers crossed that the first of
0:19:49 > 0:19:51this new generation of Chatham albatross
0:19:51 > 0:19:53will return to their safe new home.
0:19:55 > 0:19:59Who'd have thought the best way to save a bird would be to plant
0:19:59 > 0:20:01its chicks in a flowerpot?
0:20:01 > 0:20:03Fantastic.
0:20:03 > 0:20:07Has to be one of the best low-tech ideas in conservation
0:20:07 > 0:20:09that I've ever heard. Top work.
0:20:13 > 0:20:19So, from flying goats and falling beavers, to albatross in flowerpots,
0:20:19 > 0:20:23moving to a new home is fraught with challenges.
0:20:23 > 0:20:27'And a most unusual and novel trip ends for Mr Beaver.'
0:20:28 > 0:20:32Finally, bizarre chimpanzee behaviour...
0:20:33 > 0:20:36..and strange messages in prehistoric art.
0:20:40 > 0:20:42But our first story starts here in the UK.
0:20:48 > 0:20:51Cumbria, northern England.
0:20:53 > 0:20:56A place where ancient legends and romantic poetry
0:20:56 > 0:20:58are woven into the hillsides.
0:21:00 > 0:21:06But in November 2014, Dave Murphy was about to write his own chapter
0:21:06 > 0:21:07in the book of the bizarre,
0:21:07 > 0:21:11when a strange figure appeared in the clouds.
0:21:13 > 0:21:15Peace, we come in peace.
0:21:15 > 0:21:16Get closer!
0:21:20 > 0:21:23Dave and his friend were out wild camping,
0:21:23 > 0:21:28finding secret corners of the country, far from civilisation.
0:21:28 > 0:21:31I just love being by myself and getting out in the hills,
0:21:31 > 0:21:34and just putting my tent up and waiting for the sunset.
0:21:38 > 0:21:42I can't think of anything else to be doing in my life, it's my passion.
0:21:44 > 0:21:47Pitching their tents on top of Dufton Pike,
0:21:47 > 0:21:50they thought they'd left everyone else behind.
0:21:53 > 0:21:56I've seen some amazing things on the hills when I've been out,
0:21:56 > 0:21:58but nothing compares to seeing what I seen that day.
0:21:58 > 0:22:01I just remember it being a nice morning,
0:22:01 > 0:22:05the sun was shining and I could see the clouds sort of coming in,
0:22:05 > 0:22:08and it just looked a lovely morning.
0:22:08 > 0:22:11A strange, shadowy figure had followed them.
0:22:11 > 0:22:13Oh, look at that!
0:22:13 > 0:22:17How bright it is!
0:22:17 > 0:22:18It comes and goes.
0:22:18 > 0:22:21It can be there for a second, and then it can be gone.
0:22:21 > 0:22:23Back again, look.
0:22:23 > 0:22:25DAVE LAUGHS
0:22:25 > 0:22:29It's getting further away though, isn't it?
0:22:29 > 0:22:33The figures inside can actually be small and then go large again,
0:22:33 > 0:22:35so it was like it's sort of focusing in and out.
0:22:35 > 0:22:38It's unbelievable, unbelievable.
0:22:38 > 0:22:40Looks like two aliens, you know, Jonathan?
0:22:40 > 0:22:43Look at that, look at that!
0:22:43 > 0:22:47And Dave isn't the only person to have seen these strange spectres
0:22:47 > 0:22:48in the sky.
0:22:48 > 0:22:52All over the UK, people were uploading videos to the internet.
0:22:56 > 0:22:59What on earth was it that these people were witnessing?
0:23:01 > 0:23:05Well, they're known as Brocken Spectre,
0:23:05 > 0:23:08and their appearance is all about perfect alignment.
0:23:10 > 0:23:15When you get some elevation above a layer of cloud and the sunlight's
0:23:15 > 0:23:20behind you, that's when you can sometimes see one of these eerie,
0:23:20 > 0:23:21strange optical phenomena...
0:23:26 > 0:23:28..that are to do with your shadow
0:23:28 > 0:23:30and the sunlight bouncing back at you.
0:23:30 > 0:23:36So, far from being a spooky figure, the Brocken Spectre is in fact...
0:23:36 > 0:23:38Well, it's you.
0:23:38 > 0:23:43As your shadow is cast down onto the layer of cloud below you,
0:23:43 > 0:23:45your shadow seems strangely distorted.
0:23:45 > 0:23:51Your head seems very, very small and your legs very, very large.
0:23:51 > 0:23:54This is simply the dramatic effect
0:23:54 > 0:23:56of the perspective as a shadow
0:23:56 > 0:23:58recedes away from you.
0:23:59 > 0:24:06The other strange phenomenon is a halo of rainbow colours.
0:24:06 > 0:24:09These tiny droplets of cloud scatter
0:24:09 > 0:24:10the sunlight back at us,
0:24:10 > 0:24:12and the way the sunlight is
0:24:12 > 0:24:14scattered, is different depending
0:24:14 > 0:24:19on the wavelengths. For this reason, we get this separation,
0:24:19 > 0:24:20this ring of colours around the shadow.
0:24:23 > 0:24:28The apparition is your own shadow, surrounded by a rainbow halo
0:24:28 > 0:24:33created by the sun's rays reflected and refracted by the water droplets.
0:24:35 > 0:24:38And for those of you who don't regularly climb mountains,
0:24:38 > 0:24:39never fear.
0:24:39 > 0:24:43There is another place to see this bizarre phenomenon at work.
0:24:49 > 0:24:50So they're just shadows.
0:24:50 > 0:24:53There's no need to be scared of a Brocken Spectre.
0:24:54 > 0:24:58Well, actually, legend has it that seeing one is a bad omen,
0:24:58 > 0:25:00a really bad omen.
0:25:00 > 0:25:03A foretelling of your own death.
0:25:03 > 0:25:06Perhaps because stormy weather had closed in below you,
0:25:06 > 0:25:09or you'd ventured too close to the edge to get a better look.
0:25:12 > 0:25:16For centuries, we've gazed up into the skies, searching for answers.
0:25:16 > 0:25:20And these days, science can explain some of these bizarre apparitions.
0:25:20 > 0:25:23We know what they are, how they work.
0:25:23 > 0:25:26But that, nevertheless, can't detract
0:25:26 > 0:25:28from their simply awesome beauty.
0:25:33 > 0:25:38So, from legends in the sky to strange signs in the trees.
0:25:43 > 0:25:45March 2011.
0:25:45 > 0:25:49A research team are deep in the Forest of Guinea in Western Africa.
0:25:49 > 0:25:52They were studying an area for the very first time
0:25:52 > 0:25:54when they noticed something strange.
0:25:59 > 0:26:01I was at the back of the group that day,
0:26:01 > 0:26:03because I got caught in some thorns.
0:26:03 > 0:26:07So when I caught up, the group had stopped and we were gathered around
0:26:07 > 0:26:12these markings on a tree, which the main field guide had found.
0:26:14 > 0:26:16They looked really innocuous.
0:26:16 > 0:26:19I mean, it would be impossible to tell what they were.
0:26:25 > 0:26:27We weren't sure if they were wild pigs,
0:26:27 > 0:26:30or if they were human created or if they were cows.
0:26:30 > 0:26:34What they'd found was utterly baffling.
0:26:34 > 0:26:38Strange notches on a tree, and below them, large piles of rocks,
0:26:38 > 0:26:41seemingly placed there deliberately.
0:26:42 > 0:26:46Laura set up camera traps to see who or what had made them.
0:26:51 > 0:26:54Two weeks later, she recovered the footage.
0:26:55 > 0:26:57What we saw was really incredible.
0:26:57 > 0:27:02It was a male chimpanzee arriving at the site, pausing,
0:27:02 > 0:27:05looking around and picking up quite a large stone...
0:27:07 > 0:27:10..and flinging it at the tree.
0:27:10 > 0:27:14We didn't know what it could mean, we didn't know how common it was,
0:27:14 > 0:27:16we didn't know if it was just a once off event.
0:27:21 > 0:27:24So, a chimp throwing a stone against a tree.
0:27:24 > 0:27:27What's so weird about that?
0:27:27 > 0:27:30Well, the problem is, you see, explaining WHY a chimp would want to
0:27:30 > 0:27:32throw a stone against a tree.
0:27:32 > 0:27:33There's no obvious reason.
0:27:33 > 0:27:36It is, in fact, a great ape mystery.
0:27:39 > 0:27:42Anybody that's been to the zoo knows that chimpanzees can throw stones.
0:27:42 > 0:27:44I mean, that's not new.
0:27:44 > 0:27:47The really new and interesting thing is that they come back to the same
0:27:47 > 0:27:49site with the same repeated behaviour,
0:27:49 > 0:27:52and only at certain specific locations.
0:27:54 > 0:27:57But as her cameras gathered more footage,
0:27:57 > 0:28:00Laura realised this wasn't an isolated case.
0:28:00 > 0:28:02This was a real phenomenon,
0:28:02 > 0:28:05and it had never been reported anywhere before.
0:28:08 > 0:28:09What we were seeing was something
0:28:09 > 0:28:12that had never been seen before in chimpanzees.
0:28:15 > 0:28:19It seems like a new level of tool use. It was astounding.
0:28:24 > 0:28:28So, what on earth were humans' closest relatives doing?
0:28:32 > 0:28:35Laura quickly ruled out the most obvious answer.
0:28:35 > 0:28:39Unlike other examples, termite fishing, cracking nuts
0:28:39 > 0:28:44and making spears, this behaviour wasn't connected to finding food.
0:28:44 > 0:28:48So we checked the area to check that there was no fruit trees that it
0:28:48 > 0:28:51could be affecting, or any different kind of food source that it
0:28:51 > 0:28:53could be related to.
0:28:53 > 0:28:57And it really is quite sure that it's nothing to do
0:28:57 > 0:28:58with gaining food.
0:28:58 > 0:29:01Could it have been a male status display,
0:29:01 > 0:29:05an aggressive show of dominance that sometimes involves throwing stones?
0:29:10 > 0:29:13No, it wasn't, because it wasn't just males doing this.
0:29:13 > 0:29:16Teenagers and even mothers with babies had been captured
0:29:16 > 0:29:18by the camera traps.
0:29:20 > 0:29:24So what could inspire this ritualised act of chimpanzee vandalism?
0:29:26 > 0:29:29Laura developed two main theories.
0:29:30 > 0:29:35So, chimpanzees live in close-knit groups and they defend territory.
0:29:35 > 0:29:38And so there's other groups around their boundaries,
0:29:38 > 0:29:43so maybe these stone cairns are symbolic of a chimpanzee's territory
0:29:43 > 0:29:45that they protect.
0:29:46 > 0:29:51Theory one. It's possible that the rock piles are territorial markers,
0:29:51 > 0:29:55a way for the chimps to declare their space in the forest.
0:29:58 > 0:30:02But it's theory two that Laura feels is most likely.
0:30:04 > 0:30:08Chimpanzees, during the day, they'll split off into subgroups,
0:30:08 > 0:30:11but they'll often communicate with things like calls and drumming,
0:30:11 > 0:30:14and doing a loud pant hoot.
0:30:14 > 0:30:17And it was this call, the pant hoot,
0:30:17 > 0:30:19that was Laura's most convincing clue.
0:30:22 > 0:30:24It's generally thought of as a long-distance call.
0:30:24 > 0:30:30It kind of starts out like "Hoo-hoo-hoo-hoo-ah-ah-ah-ah!"
0:30:35 > 0:30:37Often, when you see a chimp doing this,
0:30:37 > 0:30:39if you can really study the community,
0:30:39 > 0:30:43you see that other individuals will actually change direction.
0:30:43 > 0:30:46It seems like there's signals being given that affect other members
0:30:46 > 0:30:48in the group.
0:30:48 > 0:30:52And so possibly this stone throwing is an add-on to that,
0:30:52 > 0:30:54and therefore maybe it's a kind of chimpanzee Morse code.
0:30:57 > 0:31:03So this strange behaviour could be a form of territorial marking.
0:31:03 > 0:31:05It could be a form of communication.
0:31:05 > 0:31:10But then, some truly extraordinary new evidence came to light.
0:31:15 > 0:31:19Researchers across Western Africa started to look out for
0:31:19 > 0:31:21telltale notches on the trees.
0:31:22 > 0:31:25Three of the four subspecies reported nothing.
0:31:27 > 0:31:29But sites in neighbouring Guinea-Bissau,
0:31:29 > 0:31:35Liberia and the Ivory Coast reported positive sightings.
0:31:35 > 0:31:38These groups either passed the ritual to each other,
0:31:38 > 0:31:43or they've developed this behaviour entirely independently.
0:31:43 > 0:31:45This wasn't an isolated incident.
0:31:45 > 0:31:50It was occurring across the species range, and that meant that
0:31:50 > 0:31:55the scientific community became immediately a lot more interested.
0:31:55 > 0:31:59And one rather bizarre theory surfaced.
0:32:02 > 0:32:06They seem to be responding to something in the space
0:32:06 > 0:32:08that we can't see.
0:32:16 > 0:32:19There's something in that space that they're returning to,
0:32:19 > 0:32:23that is fascinating to them, that has a hold over them.
0:32:27 > 0:32:31Is there a memory that they have attached to that particular spot,
0:32:31 > 0:32:36like the death of a member of their clan, or a leader of their clan?
0:32:36 > 0:32:39Or was there some other anomaly at that site,
0:32:39 > 0:32:42like a lightning strike, or a fire,
0:32:42 > 0:32:46or a particular storm that they witnessed together?
0:32:46 > 0:32:51We might never have an answer to the question of why a particular space
0:32:51 > 0:32:54seems to have become charged,
0:32:54 > 0:32:58seems to have become electrified for these chimpanzees.
0:32:58 > 0:33:02But similarly, we don't necessarily have good answers as to why it is
0:33:02 > 0:33:06that our sacred spaces have become charged or electrified for us.
0:33:10 > 0:33:14OK. Now, identifying these sites as chimpanzee sacred spaces
0:33:14 > 0:33:20might seem a little crackpot. But, when you think back to our own past,
0:33:20 > 0:33:23and how human beliefs were formed,
0:33:23 > 0:33:26it's not really as crazy as it sounds.
0:33:26 > 0:33:31If we go back to the beginning of human beings as a species,
0:33:31 > 0:33:35which is generally believed to be about 50,000 years ago,
0:33:35 > 0:33:37we would be seeing a range of behaviours
0:33:37 > 0:33:38that looked very similar to this.
0:33:42 > 0:33:47The religions that we have now would be the descendants of these
0:33:47 > 0:33:51amalgamations of early human behaviours that would have looked
0:33:51 > 0:33:54like these animal rituals.
0:33:54 > 0:33:58Perhaps we'll never fully understand why these chimpanzees engage
0:33:58 > 0:34:00in such bizarre behaviour.
0:34:00 > 0:34:03But for Laura, this discovery is just the beginning.
0:34:03 > 0:34:08I do think that we constantly underestimate other species.
0:34:08 > 0:34:12And so, I think it's worth wondering what this could mean in,
0:34:12 > 0:34:14potentially, a higher sense.
0:34:14 > 0:34:17And I think the real thing that we should take from this is
0:34:17 > 0:34:20how important it is to protect the future of these chimpanzees,
0:34:20 > 0:34:23because I'm sure there's a lot more
0:34:23 > 0:34:25to discover that we haven't yet seen.
0:34:26 > 0:34:28Who'd have thought it?
0:34:28 > 0:34:33A few mysterious notches on a tree growing into such a great mystery.
0:34:33 > 0:34:35But we really shouldn't worry.
0:34:35 > 0:34:38Planet of the Apes? Well, it's not round the corner.
0:34:38 > 0:34:40Well, not quite yet, anyway.
0:34:42 > 0:34:47So, from chimpanzee rituals that tell us about the beginnings of
0:34:47 > 0:34:51human religions, to early human religions that might just point
0:34:51 > 0:34:56to a god of a very different kind. Something totally alien.
0:35:00 > 0:35:0311th of May, 2002.
0:35:04 > 0:35:07An expedition is exploring the deserts of Gilf Kebir,
0:35:07 > 0:35:10the great barrier in the Egyptian Sahara.
0:35:10 > 0:35:14And at 4.30 in the afternoon, with the sun burning down,
0:35:14 > 0:35:21Jacopo Foggini sought out shade in a cave and made a startling discovery.
0:35:27 > 0:35:30Thousands of cave paintings.
0:35:30 > 0:35:338,000 years old.
0:35:33 > 0:35:36One of the most important prehistoric sites ever discovered.
0:35:39 > 0:35:43The big question everybody's asking about this cave is,
0:35:43 > 0:35:46"What the heck are these animals?"
0:35:46 > 0:35:49These big animals.
0:35:49 > 0:35:50And the beast, what is it?
0:35:50 > 0:35:54Whilst most were fascinated by the strange images
0:35:54 > 0:35:57of headless creatures, one archaeologist
0:35:57 > 0:35:59was drawn to something else.
0:35:59 > 0:36:01Something everyone had overlooked.
0:36:03 > 0:36:07When I arrived on the site, I did not believe my eyes.
0:36:14 > 0:36:17I immediately noticed the tiny stencil hands.
0:36:17 > 0:36:20There were 13 of them, and I thought,
0:36:20 > 0:36:24"Wow, it's really different from any stencil hand
0:36:24 > 0:36:26"I've seen before in my career."
0:36:27 > 0:36:31Prehistoric handprints have been found at cave art sites all over
0:36:31 > 0:36:34the world, from Australia to Argentina.
0:36:34 > 0:36:37And in evolutionary terms, they're fascinating.
0:36:37 > 0:36:41They provide one of the first insights into humans developing
0:36:41 > 0:36:43a sense of self.
0:36:51 > 0:36:57Look at that. It's a signature, a sort of prehistoric spray tag.
0:36:57 > 0:37:00But the prints that fascinated Emmanuelle
0:37:00 > 0:37:03were altogether more bizarre.
0:37:03 > 0:37:05What she'd found weren't just handprints.
0:37:05 > 0:37:11Inside each of the 13 larger ones was strange, second, smaller print.
0:37:11 > 0:37:15All of the experts had assumed that they were children's hands.
0:37:15 > 0:37:17But Emmanuelle wasn't so sure.
0:37:20 > 0:37:25We did some measurements on dozens of pre-term new-borns,
0:37:25 > 0:37:30and even if they were matching in terms of hand length,
0:37:30 > 0:37:32the proportions were really different.
0:37:33 > 0:37:37With a probability of less than 0.01%,
0:37:37 > 0:37:42Emmanuelle proved that humans hadn't made these handprints.
0:37:43 > 0:37:46But who, or what, had?
0:37:49 > 0:37:53My first hypothesis was, it could be monkeys' hands.
0:37:53 > 0:37:57And for that time, 8,000 years ago,
0:37:57 > 0:38:01imagine that people have taken monkeys under their shoulders
0:38:01 > 0:38:05and stencilled their hands, it was really crazy to imagine it.
0:38:06 > 0:38:10Crazy maybe, but impossible, certainly not.
0:38:10 > 0:38:12But no matter which monkey she tested,
0:38:12 > 0:38:17she just couldn't get the thumb in the right place.
0:38:17 > 0:38:20Emmanuelle was at a loss, but there were some other theories
0:38:20 > 0:38:22out there she couldn't ignore entirely.
0:38:26 > 0:38:29Our first publication was about telling it's not human.
0:38:29 > 0:38:32But we didn't find yet the solution,
0:38:32 > 0:38:36so after that I got plenty of e-mails telling me,
0:38:36 > 0:38:38"Would you investigate the alien path?"
0:38:38 > 0:38:41And I thought, "But how can I measure aliens?"
0:38:43 > 0:38:45But Emmanuelle wasn't quite ready to
0:38:45 > 0:38:46give up on a more terrestrial answer.
0:38:49 > 0:38:52We did a lot of measurements on the hands of crocodiles
0:38:52 > 0:38:57and the match was quite good, but it was not 100% convincing.
0:38:59 > 0:39:04After nearly ten years, her search had become an obsession.
0:39:04 > 0:39:09At this point, we had investigated the human path, monkey path,
0:39:09 > 0:39:14the crocodile path, and no-one was really matching.
0:39:14 > 0:39:17I have to confess, it began to haunt my dreams.
0:39:19 > 0:39:23Determined to find an answer, she scoured the records
0:39:23 > 0:39:26and discovered one animal, no longer found in the area,
0:39:26 > 0:39:29that would have once walked the dunes here.
0:39:32 > 0:39:37This desert monitor lizard had lived here 8,000 years ago.
0:39:37 > 0:39:39I contacted a lot of crocodile farms,
0:39:39 > 0:39:44and I realised they were also keeping a lot of monitor lizards.
0:39:44 > 0:39:47So I asked them if they would enjoy
0:39:47 > 0:39:49to take part in the study,
0:39:49 > 0:39:53and to my surprise they were all very enthusiastic.
0:39:55 > 0:39:58Hunted for centuries by humans for their skins,
0:39:58 > 0:40:02these throwbacks to the time of dinosaurs were in the right place
0:40:02 > 0:40:03at the right time.
0:40:03 > 0:40:08But could they be the source of the non-human handprints?
0:40:09 > 0:40:12When I got the final result, I couldn't believe my eyes.
0:40:12 > 0:40:15We got the closest match with lizards,
0:40:15 > 0:40:20and they are actually matching with more than 85%.
0:40:21 > 0:40:25But one vital question remains.
0:40:25 > 0:40:29Why were they using these lizard feet in the first place?
0:40:30 > 0:40:36We have no evidence of a reptile worship, but the fact that
0:40:36 > 0:40:41those hands are stencilled exactly as the human ones are done,
0:40:41 > 0:40:47it does testify of really different relationship to nature
0:40:47 > 0:40:49than the one we have today.
0:40:49 > 0:40:53Today, we consider that humans are separated from nature.
0:40:53 > 0:40:58But in animalistic societies, people consider that
0:40:58 > 0:41:04they are equivalent of any living entity in the world.
0:41:05 > 0:41:08After ten years of enquiry,
0:41:08 > 0:41:11I really feel happy to have found the solution!
0:41:11 > 0:41:13So now I can sleep at night.
0:41:16 > 0:41:19So, from humans to monkeys, from crocodiles to aliens
0:41:19 > 0:41:22and finally to the desert monitor lizard,
0:41:22 > 0:41:25what Emmanuelle has proved here is that to solve
0:41:25 > 0:41:27the perfect prehistoric riddle,
0:41:27 > 0:41:29you've got to pull out all of the stops.
0:41:29 > 0:41:31Determination is key.
0:41:33 > 0:41:37From weird clouds bringing portents of doom,
0:41:37 > 0:41:42to a chimpanzee ritual that sheds light on our own early religions.
0:41:42 > 0:41:46And a prehistoric discovery that hints at a very different set
0:41:46 > 0:41:47of beliefs entirely.
0:41:49 > 0:41:52We've found that in our search for deeper meanings,
0:41:52 > 0:41:56some of the answers can be found in the most unexpected places.