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00:00Oh
00:30Dolphins are the most loved of all the creatures in the sea.
00:38They dazzle us with their beauty and grace, they inspire affection and even awe.
00:44I love dolphins, we've seen quite a few dolphins and whales and it's just addictive, you just
00:51have to go out there and see them again, just inspiring I think.
00:58The dolphins seem to like us too.
01:01Scenes like this have formed our image, friendly, loving and very intelligent, a creature that
01:08we could learn so much from.
01:10I actually do want to look at their faces, I want to, you know, have people talk about
01:16making eye contact, I would quite like to make eye contact with a dolphin, I wish I'd got
01:21the courage to actually get in the water, you know, like some people do and swim with them.
01:26But are we taking a risk?
01:29Would we let our child pat a strange dog?
01:32The dolphin is a wild animal, a 300 pound skilled predator.
01:37Some scientists think we may be making a mistake.
01:40I certainly think it's not ever a wise thing to swim with some of these wild groups of dolphins,
01:45I think one thing we're talking about very big animals, so if they decide even to be playful
01:48with you, you still stand a chance of injury.
01:53A look beneath the surface reveals some startling facts about how they live their lives.
01:57Head-to-head, these two males right here, head-to-head fight, a tiff, a tiff between these two males.
02:02They're head-to-head.
02:03They have another side to them.
02:06They can be aggressive and nasty, just like we can.
02:12Are dolphins nice or nasty?
02:15And how much do we know about what's going on in their minds?
02:19For the first time, animal behaviourists are taking the techniques of studying land animals
02:23under water to penetrate the secret world of dolphins and learn the truth about how
02:29they live their private lives.
02:33Until recently, almost everything we knew about dolphins was learned from captive animals.
02:46But behaviour in captivity gave little indication of how they would behave in the wild and of
02:51their natural relationships.
02:53Performing tricks led us to believe in their intelligence and the bottlenose dolphin was
02:57found to have the biggest brain for its body size of any animal besides humans.
03:01their communication system signalled a well-developed language and dolphin devotees believed that
03:12one day we might even learn to talk to dolphins.
03:15They use whistles to communicate with each other.
03:18They also have a type of sonar called echolocation, a series of clicks which bounce back from objects
03:23in their path.
03:25All dolphins seem to use echolocation and along with whales have a common ancestor.
03:30It was a meat-eating mammal, 55 million years ago it ventured into the water to feed.
03:42Over time its descendants grew more adapted to life in the sea.
03:46Bodies became streamlined, forelegs became flippers and hind legs gradually disappeared.
03:57This was the ancestor of all whales and dolphins, an air-breathing mammal modified by evolution
04:03for life in the sea.
04:07But because their world is an environment alien to humans, we had no idea how dolphins live their lives,
04:18what they might have in common with other mammals.
04:20But that's starting to change.
04:23Three groups of scientists have developed ways to look at how they live their lives in the wild.
04:32In Sarasota Bay off the Gulf Coast in Florida, the first long-term study of a community of
04:37wild bottlenose dolphins began over 20 years ago.
04:43Randy Wells started following these dolphins when he was still at high school.
04:47I feel like I know more about many of these animals out here than some of the people I went to high school with in the same area 20-some years ago.
04:55We've been keeping close track on them, on some of them now, for 22 years, following them through multiple generations.
05:01We now have several grandmothers out there and their daughters and their daughters have given birth to offspring as well.
05:06Randy Wells' community of street-wise urban bottlenose dolphins are used to dodging speedboats and people and to murky tropical waters.
05:18The core community consists of a hundred or so.
05:218,000 miles from Florida, another community of bottlenose dolphins are being studied.
05:29These dolphins crave human company, and these warm, crystal-clear waters in Western Australia are a perfect location.
05:36Richard Connor and Rachel Smoker began their research here in 1981.
05:41Well, we'd both been interested in dolphins for a long time, and a woman who had been to Australia, to Shark Bay,
05:47came to Santa Cruz and did a little song and dance and told us about the dolphins there and that there's nobody there studying them.
05:52And we both decided we had to go.
06:11Conditions here are very different from Florida.
06:13The shallow, transparent waters of Shark Bay are like a large aquarium.
06:17The intricate interaction of a community could be observed for the first time.
06:26Richard and Rachel found they could follow the dolphins for 10 to 12 hours a day, observing every detail of their private lives from a simple dinghy.
06:38The roaring waves and freezing waters of the Moray Firth in Scotland couldn't contrast more with the other two study areas.
06:45Paul Thompson and Ben Wilson from the University of Aberdeen have been working with a bottlenose dolphin community of about 130 animals for just on five years.
06:56This research team has built on the work of the other two groups, but these freezing waters make their job a good deal more difficult.
07:03When one looks at Randy Wells, and he's standing in the water with his colleagues for hours looking after dolphins, if we were to try that here, we'd be dead within half an hour.
07:16But the difference in the environment does provide a really interesting situation for seeing how the behaviour of the animals, and perhaps particularly their social behaviour and their mating patterns, varies according to the environment that they're living in.
07:30Paul and Ben are studying the most northerly community of bottlenose dolphins in the world.
07:39In these waters, even distinguishing their sex is a major problem.
07:42Because the water is like tea, the moment they're under the water, you can't see very much, and they don't look on the surface, bottlenose dolphins don't look different, males and females look very similar.
07:54Obviously, if they go two or three feet down, they haven't got a chance.
07:57They're right between me and you, right?
08:00Already, the work of these three teams allows us to get an insider's view of the dynamics of dolphin society.
08:09In Florida, Randy Wells uses a capture and release methodology. Once a year, he carries out physical checks on several of them.
08:21Two boats have followed a pair of dolphins into shallow water.
08:27Now they need to coordinate their movements perfectly so as not to startle or frighten the animals.
08:34Although they repeat this process each year, getting it right requires patience and skill.
08:46At full speed, they drop a 1,500-foot curtain of net in a big circle around the animals.
09:03The rest of the team, biologists, vets, trained dolphin handlers and a small army of volunteers, come in to help.
09:16They end up with a corral right in the shallow bay with the two dolphins inside it.
09:34This group will spend a few hours with the dolphins, learning every detail about them. Once they've done that, the animals will be released.
09:52At first, it's just observation. Later, a group of volunteers remains in the corral while each animal in turn is taken aboard a laboratory boat for physical checks.
10:06The capture of wild animals like this requires special permits.
10:13Randy Wells' work with these Sarasota dolphins is so highly regarded and his methods so skilled, he has been able to continue this program for more than ten years.
10:25By now, he has built up records of almost the entire core community of some 100 dolphins.
10:35And for most of this group, he has individual profiles.
10:46This is a ten-year-old male. He's been examined once before, and Randy has known him since birth.
10:54Dolphins born before the study began are aged by examining their teeth. Some are in their 40s and 50s.
11:11This is a simple check to monitor growth rates and general health.
11:17One of the most important procedures is the blood test. The sample from this ten-year-old will be used to test for pollutants,
11:37but its most significant function is in genetic identification. Randy wants to know who fathered this dolphin.
11:45That will show whether these animals mate within their core group or with dolphins outside the community.
11:52Over the years, the results of the analysis have surprised him, and may turn out to be highly significant in the light of the research elsewhere.
12:03Nice job, group.
12:09Yeah, there's some moving right down here.
12:16Capture and release is the highlight in a year-round research program.
12:20Combining information from the physical checks and observation, Randy has been able to piece together a picture of the architecture of dolphin society in this bay.
12:29The pattern of relationships between mothers and babies, siblings and outsiders.
12:35Building up a picture of this community has taken years of dedication.
12:40Results came slowly at first.
12:42The male pair I was talking about before.
12:44There were thousands of hours of painstaking observation.
12:46Location is Quick Point.
12:48That's right. Quick Point.
12:50Each sighting is noted.
12:52Still travel over shallows?
12:53Yes.
12:54How old are these guys, Randy?
12:56They're in their late teens.
12:57They're about a year apart in age.
12:59We've known 36 since 1975, and 38 we first identified in 1980.
13:07They formed a very tight bond.
13:11Randy now knows 150 animals by sight.
13:15Every sighting is also photographed.
13:18The photograph ID is then checked against the notes.
13:21Dorsal fins are the most certain form of identification.
13:24See how distinctive the fin is on 38?
13:26He's got a cut-off tip and then two low notches.
13:29And that's true for bottlenose dolphins all over the world.
13:35Nearly every dolphin the team has seen in the last 20 years here has been photographed and catalogued.
13:40That's about 1,200 dolphins along 120 miles of coastline.
13:45This one's up here.
13:47I think it's this one.
13:48Pictures from each observation period are compared with those on file.
13:51It's a way of confirming actual sightings.
13:53Different touch.
13:58Randy now knows more about social relationships and family dynamics in this core community than anyone.
14:03He's learned that about 100 dolphins live in the bay.
14:09It's a stable, resident community moving in a home range of around 75 square miles.
14:17The females have calves from the age of 12 or 13 when they reach sexual maturity.
14:22They continue to calf well into their 40s.
14:25Bands of related females, mothers, grandmothers and babies swim together.
14:30They socialize and even babysit for each other.
14:35Sharks are a serious threat here and 20% of baby dolphins do not survive their first year.
14:41It may be that the largest female bands are one way of protecting the young.
14:46Despite the dangers, sometime from the age of three, young calves leave their mothers to swim with their peer group.
14:52They do this until sexual maturity.
14:55Females return to their mothers group to raise their young.
15:01The males leave their mothers permanently at about the age of six, often forming tight pair bonds with other males.
15:08These pairs could be inseparable for years, perhaps even for life.
15:13Randy has noticed that dolphins appear to form very firm relationships.
15:18Moving from one companion to another daily, yet always within the same core community.
15:24In these murky waters, he couldn't find the answer to his next question.
15:30How were these bonds expressed and maintained?
15:41It was at Shark Bay in Australia that researchers began to unravel what was going on between the members of the community.
15:47Richard Connor is concentrating on the behaviour of male dolphins.
15:52Rachel Smoker is researching communication.
16:00Janet Mann is following the development of mothers and babies.
16:03Here she's with the matriarch of the Shark Bay community, Holy Finn, a 30-year-old grandmother now pregnant once again.
16:11The white patches along Holy Finn's back are sunburned scars.
16:18The first time Richard Connor followed the dolphins across the bay,
16:21he was excited by the possibilities.
16:24They're wild, but they're so habituated to our boat that we can follow them for up to ten hours at a time,
16:30staying within ten metres of them, and it appears that they just ignore us.
16:33They just go about their business, socialising with each other, feeding, whatever they're going to do, and we can just watch.
16:39That was a good example of baby position, what we call baby position when the baby rests underneath the mom, travels along with her.
16:51Janet Mann has been monitoring the bonds between mothers and infants.
16:55She saw the same female groups as in Sarasota, but here she can see how these family bonds are formed and compare dolphin development with that of other mammals.
17:08Like some others, dolphins have an extremely long and dependent childhood.
17:14Dolphin birth has never yet been observed in the wild, but it's often been seen in captivity.
17:33Dolphin babies are physically precocious.
17:36They have to swim from the moment of birth, but they remain dependent on their mother for up to six years.
17:43It's an extraordinarily extended period.
17:47Dolphins need this lengthy childhood to learn the skills of survival.
17:52The fact that it is so long is the evidence for how much there is to learn.
17:56We're following Yoda. She's a new baby this year.
18:05And she's pretty independent. She's been going well over 100 metres from her mom.
18:11Yoda will rely on her mother's milk for up to two years more.
18:16But meantime, she's practising her hunting, preparing for the day when she will feed herself.
18:21She's fishing.
18:22She's snacking on some tiny fish, little gar fish.
18:31There you go. She just snapped at one. Oh no, don't lose it on the boat.
18:36Yoda is one of 25 calves Janet is studying.
18:41She's noticed that some of the babies leave their mothers frequently, going off for hours at a time.
18:46She was puzzled. Why did they stray so far? And how do they find their way back when they've been apart?
18:55Six I think, six or seven.
19:00Today she's following Yoda, and she's joined by Rachel Smoker, who's working on how dolphins communicate.
19:07Rachel is following Jan, the mother.
19:13The idea is to record the son's mother and daughter exchange in getting back together.
19:18There he is. Can you hear that?
19:21It's Yoda's whistle.
19:23So I can see Yoda. Yoda's beelining towards us.
19:27Here's Jan, she's about 15 metres from us.
19:32Here's Yoda, right behind us, still beelining towards Jan.
19:36So those whistles were getting louder and louder as Yoda was approaching.
19:40Mother and baby are now happily reunited.
19:43In these clear waters, Rachel can test in natural conditions the research done on whistles in Sarasota Bay.
19:55This team started the research on dolphin whistles during their annual capture and release sessions.
20:02A microphone is attached to every animal they examine.
20:06Dolphins make sounds in their nasal cavities.
20:08The sounds pass through the melon, which is a waxy mass of tissue at the front of the head, directly into the water.
20:22It acts like an acoustic lens, focusing the sound to give it direction.
20:27Dolphins do not have to open their mouths to communicate.
20:31This made it difficult for researchers watching dolphins to determine which animal was making a particular sound.
20:38The only way to be sure was to record directly from the melon.
20:51Dolphins begin whistling at birth and soon develop their own unique signature whistles.
20:57Researchers suspect they may use them like names to keep track of each other in a murky underwater world.
21:02This experiment is designed to see whether one animal can identify another dolphin by its whistle.
21:09White strings form a visual grid over the dolphin, so its movements can be measured on videotape.
21:15Everybody just be quiet, please.
21:16Through an underwater speaker, the signature of a dolphin known to be a close associate to the one held in the corral is played back.
21:26It's alternated with the signature whistle of another dolphin, not as close, but from the same community.
21:36Analyzing the tape later, it's shown that the dolphin reacts more strongly to the sound of her friend, evidence for the first time that a dolphin can recognize another individual by its signature whistle.
21:50There have also been reports of dolphins using each other's whistles, perhaps like calling a friend by name.
22:03Back in Shark Bay, Rachel and Janet have witnessed how the whistles work in practice.
22:07Yoda is back with her mother, but that leaves Janet's second question unanswered.
22:14If a baby leaves the mother, it's probably under much higher risk of predation or getting stranded or lost from the mother.
22:24It might be very difficult to find her, which is death to an infant if it can't find its mother.
22:29Why do they have to do it? That's a puzzle.
22:32She believes it's probably because there's something much more important going on.
22:39That's social bonding, getting to know other members of the group.
22:43Developing these relationships keeps babies away from their mothers for long periods.
22:48They're keeping very tight around Puck.
22:51Janet is now following Cookie, a three-year-old male.
22:55He's been away from his mother all morning playing with his sister, Puck.
22:58They're joined by Rabble, also a three-year-old male, on leave from his mother.
23:05Rabble and Cookie are frequent companions.
23:11Puck is Cookie's big sister.
23:15She's about ten years older than he is.
23:21They're very tight.
23:24They engage in a lot of social, sexual behavior together.
23:32Now there's starting to be some active petting.
23:36Puck, who's female, it's very common for her to go belly up under males and do this kind of rub along the male's pec fin.
23:47He's jerking a little bit, but she's doing most of the active movement.
23:52And now Rabble's come over and joined the two of them.
23:55They're all very tight together again.
23:56That's for the 13, 25, also group comp.
24:0122, 16.
24:03Both males behind her.
24:05They come up, Puck goes on side.
24:07Suddenly there's a change.
24:10The fondling play seems to become more explicitly sexual.
24:14Cookie and Rabble begin mimicking adult courtship behavior.
24:18And simultaneous sort of goose on Puck's peed uncle.
24:2222, 30.
24:23They're all in contact with the nearest neighbor.
24:26See, both males have erections.
24:28And they're both poking into her, trying to poke into her gentle area, but she goes on side.
24:34Cookie is quite an erection.
24:37And Puck goes on side.
24:38Cookie pushes up underneath.
24:41Now she goes, Puck goes belly up.
24:43And Cookie rubs his penis alongside her peed uncle again.
24:49Rubs up against her again.
24:51Looks like he's sort of attempting a mount, but Puck's not quite letting him do that.
24:57She goes on side.
24:5918, 47.
25:01He's trying what he can.
25:04Puck seems to be willing to let the younger males practice their sexual behavior.
25:08She's in control, but letting them try out sexual strategies.
25:13So does Rabble.
25:15The researchers have noticed that young males in particular seem to need this practice.
25:19Both males.
25:21It appears that although this looks serious, it is just play.
25:25And it can change quickly.
25:27Baby position with Puck.
25:29A minute ago, he was doing the sexual stuff with Puck.
25:32Now he's acting like her infant.
25:36But Rabble and Puck are not related as far as we know.
25:45This is really weird.
25:47Look, he's trying to nurse.
25:49He's sticking his rostrum to the mammary slit.
25:55This is just amazing.
25:57Puck lost her baby about six weeks ago.
25:59I mean, it's possible that she would still have a little bit of milk.
26:03But it seems unlikely.
26:05Anyway, Rabble is clearly trying to nurse her.
26:07He's done it several times.
26:09I don't know if he's getting anything.
26:11Rabble has given up his sexual play.
26:13Apparently, he's ready to be a baby again.
26:16He leaves soon afterwards to rejoin his mother.
26:19And Puck and Cookie are splitting up too.
26:21Looks like they're splitting up.
26:23Cookie's heading to the south.
26:25Looks like she's going more to the north.
26:27Cookie spends all day moving from one social encounter to another.
26:36Slow down.
26:39That's Joy.
26:42This is Dagwood, a young male.
26:45And Cookie.
26:47Cookie lives a life filled with these relationships.
26:50Meeting with companions, playing with older sisters.
26:52These social bonds are nurtured by physical contact.
26:56Contact which is far more obviously physical or sexual than anyone ever realized.
27:02This is how dolphin calves come to know the members of their own community.
27:06And learn the rituals of social life.
27:08The physical contact seems to consolidate social bonds.
27:12And the importance of knowing members in their own community seems to answer Janet's question.
27:16That's why babies leave their mothers.
27:19But the relationship between mothers and babies tells only one side of the story.
27:28It was when they began to look at the sexual strategies of the adult males,
27:33that some startling and even unpleasant sides to dolphin behavior emerged.
27:37Like the male dolphins in Sarasota Bay, the males of Shark Bay are almost always seen in tight pairs or triplets.
27:47Richard Connor has spent more than a thousand hours in the field watching them.
27:51He wanted to know what the males were up to.
27:53One of the most striking things in following the males was their synchronous behavior.
28:00You just see them often surface in just exact, precise synchrony.
28:05And you see them perform displays around females that were like anything you've seen dolphins trained to do in captivity.
28:12Leaping out in opposite directions or crossing in mid-air.
28:15Beautiful synchronous underwater ballets around the female.
28:18Amazing.
28:20And we think it could be two things.
28:24Sort of signaling to each other that we're very tight.
28:28Or perhaps a message to other dolphins that we're very tight and you have to watch out for us.
28:35Richard noticed that male pairs would often come to the beach with single females.
28:40If the female tried to get away, they'd chase her down, sometimes biting and snapping.
28:48The males would become very synchronous in their movements and displays, as if to intimidate or impress the female.
29:03He often saw the same thing offshore, sometimes involving more than one female and more than one male coalition.
29:20That's interesting. That's the two females who are being herded.
29:24They're side by side and surfacing synchronously there.
29:27And all the males in the two different coalitions right behind.
29:30These episodes of herding might last from several minutes to several weeks.
29:37Richard thinks that it's a part of dolphin courtship.
29:43Basically, we believe that herding is a strategy to monopolize the females,
29:49prevent the female from having access to other males and other males from having access to the females.
29:53We think that by herding females, males are increasing the chance that they'll be the father of the offspring.
29:58But the females are not always easily dominated.
30:03They have their own agenda and may be making mating choices.
30:07Females may prefer one male over another.
30:11Or even within the herding context itself, it may be that females will try to escape harder from one alliance of males than from another alliance of males.
30:18And we certainly see that outside of the herding context, certain males and females appear to have special friendly relationships,
30:26which indicate to us that there certainly are other kinds of relationships and other kinds of mating strategies.
30:31For example, the old female holy fin who comes into the beach and takes fish.
30:35We often see her off with a couple old males slashing crinkles and they'll be petting with holy fin.
30:42And even when she's pregnant, even at a time when she couldn't possibly conceive.
30:47And why would they bother except that they have another kind of relationship?
30:51Could this mean that dolphins engage in sex for fun, as well as procreation, like humans?
30:56There's also a dark side to dolphins' sexual politics.
31:02A lot of people have had sort of a false notion about what dolphins are really like.
31:05I mean, dolphins can be wonderful and friendly and a lot of good things, but like any complex mammal or any not very complex mammal,
31:14they have another side to them. They can be aggressive and nasty, just like we can.
31:18Sometimes male aggression looks like bullying. In this case, a male named Patches is ganged up upon by his own partners and another coalition.
31:33The aggressive sounds are picked up by an underwater microphone.
31:36There's no way of knowing what Patches did to provoke this abuse, but he disappeared from the bay and was never seen again.
31:59Aggressive encounters take a toll on the males. They don't live as long as females,
32:03and the older they get, the more battle scars they have.
32:17Disputes sometimes arise between coalition partners.
32:21Longtime allies, Snubby and Bibi, had been getting along fine until they were joined by six other males.
32:27Then, for some reason, they begin having a tiff.
32:33It's mostly noise at first, but gradually their tiff erupts into a fight.
32:56It doesn't last long. An hour later, they'll be friends again.
32:59It typifies what kind of a complex society they live in and how context-dependent their interactions are.
33:09How you're getting along with somebody depends on what you're doing and also who you're with.
33:14Like, I might get along fine with another individual as long as we're alone, but if somebody else shows up who likes me and I like them, but hates this other individual I'm with, then I might turn on them.
33:24That's what goes on in the dolphins' lives.
33:30The most complex relations are between coalitions.
33:33Richard's been with two pairs of males since early this morning.
33:37It's Wave and Shave, along with Spud and Astro.
33:39There they go again, very tight.
33:48At the moment, they are travelling with a mother and calf.
33:52These are all the males behind the female and calf who just dove, petting between two of the males there and they go shooting down after the female.
33:59They seem to be interested in there. It's not hurting yet.
34:05These two are petting each other.
34:09Even though the male dolphins are obviously pursuing the females, there's quite a bit of friendly stroking going on among the males themselves, both within the coalitions and between them.
34:19It's typical male behaviour, a way of promoting friendly relations.
34:26Ooh, that's a little synchronous turn for the males there.
34:30That was Scud and Shave.
34:32Again, one member from each coalition.
34:36An expression of unity between the two alliances, at least for the moment.
34:40But the social landscape is about to change.
34:49Okay, they've joined up with a bunch of other dolphins here.
34:56See if I recognise any of them.
34:59Pick up some rowdy stuff now.
35:05Wave and Shave move toward a female, and suddenly a chase is underway.
35:11Whoa!
35:13We may be seeing a capture attempt.
35:20There it goes.
35:22Chasing over here.
35:23There they go, porpoising.
35:25In a few seconds, they're nearly out of sight, and by the time we catch up, it's all over.
35:31Okay, we have, I believe, a capture attempt here.
35:34There was a long chase, and these males are getting excited.
35:36I think the individual snagging there is the one they probably captured.
35:41Looks like Jasmine.
35:43Raven Shave around the female they've just apparently captured.
35:49Captures like this are the way herding usually begins.
35:52Wave and Shave seem to have Jasmine under control.
35:54Now, some other males are, looks like males coming in to join this group.
36:00It's Astro and Spud.
36:02The coalition Wave and Shave had been so friendly with earlier in the day.
36:06But things are different now.
36:08Astro.
36:10Pretty excited socializing going on down there.
36:13Some synchronous stuff.
36:14Head-to-head, these two males right here.
36:15Head-to-head fight.
36:17A tiff.
36:18A tiff between these two males.
36:19They're head-to-head.
36:21Oh, this is an interesting aggression between these two.
36:24They're lined up head-to-head, jawing at each other.
36:26And there's two more.
36:28They're growling.
36:29There's two tiffs going on here at once.
36:31I've never seen two tiffs right next to each other like that.
36:36Head-to-head, aggression.
36:38Then, as quickly as it began, the tiff is over,
36:41and the two coalitions are friendly again.
36:46Look at these guys. They're so tight together.
36:49They're touching pecs. Look at this.
36:50Petting. Look at this.
36:52Almost synchronous petting against the snout of the one in the middle there.
36:57That was a wave in the center and Shave and would be Astro on the other side.
37:03Often after an aggressive interaction,
37:05you might see dolphins pet each other and you get the sense that they're making up almost.
37:09And that's what we might have been seeing there.
37:13The on-again, off-again friendliness between alliances
37:16is something that puzzled Richard in the first years of research.
37:19We had been seeing that each alliance had one or two other alliances that they spent a lot of time with.
37:28And we knew something had to be going on there,
37:30because if alliances were simply hurting females and competing for access to females,
37:36you'd think, well, why would they ever be friendly to each other?
37:38Their relationships should be exclusively hostile.
37:40So something else must be going on.
37:45One day, he found out what it was.
37:48He'd been on the beach, watching a male coalition herding a female.
37:54Another alliance came in and approached very close, but didn't do anything.
37:59You know, we thought, this is strange.
38:00And then they turned and left, and about a mile offshore, we found them later,
38:04they had joined up with another alliance.
38:07Then they came into the beach, and they attacked and took the female.
38:13And there they go, out northwest.
38:17The kidnappers took off across the bay, with the coalition from the beach in hot pursuit.
38:21Andrew, they got Holyfin, they went in there and stole her.
38:26This is like science fiction.
38:28It was the first time Richard had seen two coalitions join forces to overpower a third.
38:36On another day, he saw a similar situation escalate into a virtual war involving two super coalitions.
38:44The chase and battles lasted an hour and a half.
38:46This explained why rival coalitions aren't exclusively hostile to each other.
38:52They may need to join forces to pursue their goals.
38:55It's part of their sexual strategy to get control of females.
39:07When you talk about political behavior in animals, you're talking about the same thing you're talking about in humans.
39:12You're talking about conflicts of interest.
39:13In animal societies, individuals need to cooperate together sometimes, but they're also in reproductive competition with each other.
39:22It seems these dolphins colluded.
39:25They joined forces to overpower and steal a female.
39:29This is the dark side of the smiling dolphin we thought we knew.
39:33And what of the Moray Firth dolphins? How much aggression is there in their social relationships?
39:49The researchers here have only been observing bottlenose dolphins for five years, but they've built on the Florida and Shark Bay studies.
39:57There are similarities, but the researchers haven't seen the collusion between males for access to females.
40:10It's absolutely fascinating because we've seen nothing like that.
40:13We obviously see fighting, we see males battling with one another, we see a lot of animals jumping around, hitting each other in the air.
40:21But we don't see the coordinated behavior of two males either side of a female, the herding that's been described elsewhere.
40:27And it's a real mystery why in the Moray Firth this isn't the case.
40:30But the bonding between mothers and their calves is clearly similar to Florida and Australia.
40:45We've got a lot of mump-carved pairs here.
40:49Each adult is accompanied by a slightly smaller individual and often these are some of these sort of four or five-year-old calves.
40:56It's the male behavior which is radically different.
41:01Here, the males are real loners.
41:04There's one called number 20 and one called, well, Black and Decker we call him and another one 19.
41:09And we see them moving great distances.
41:11They've moved over 100 kilometers once in four days and they seem to just travel all over the place.
41:19The male range is so wide, the researchers have trouble unraveling what their reproductive strategies might be.
41:26We've really been trying to describe the female distribution rather more.
41:34But even when you have a good idea what the different strategies are, you don't necessarily know who obtains the mating.
41:41After all, if you've got three males chasing one female, only one of those males can fertilize the egg.
41:45And without a blood test, you can't be sure which one did. But could it be that the females choose?
41:52We've seen some activity where a female will roll upside down or onto her back or onto her side and she'll actually protect her genital area from, you know, she'll have it actually out of the water so that the males can't get alongside her to mate.
42:03And I'm sure there's other ways by going back into a group of females and this kind of thing.
42:08I'd be very surprised if females don't have a choice about which males they actually mate with.
42:12So a distinction between sex play for social bonding and for reproduction.
42:17There's sexual activity between siblings, peers and parents and their young.
42:22But it seems that females may choose to mate outside this close community.
42:27A good example came from the study in Florida where they found that when they did paternity testing on the young, they looked at the genes and who was the mother and the father of the offspring.
42:40They found that 13 out of 14 of the young came from males that weren't in the community of animals that they were looking at.
42:48So the fathers came from a different social unit.
42:52So apparent sexual interaction between members of family groups or even the same community may be just a means of consolidating social bonds.
43:00And sexual rivalry is not the only reason for aggression.
43:04The Moray Firth Dolphins are an isolated community. Their nearest neighbours are about 800 miles away.
43:10Nevertheless, aggressive encounters do take place between resident males. What's the reason for that?
43:16It's very difficult to interpret what's going on. It's like watching a fight in a pub between humans.
43:22If you can't understand the language or you just come across what's going on, you just see the fight.
43:26You don't necessarily understand the context.
43:28And we do see quite a lot of violence between both bottlenose dolphins with other bottlenose dolphins.
43:33But we've also observed them having violent interactions with harbour porpoises in the area.
43:39Maybe that's competition for food or competition for areas.
43:43We just don't know the reasons why.
43:45But certainly it's fairly aggressive and violent interactions we see.
43:51About 30% of harbour porpoises washed up dead here have been battered to death by bottlenose dolphins.
43:5710 to 20 animals a year.
43:59This aggression cuts right across our image of the dolphin.
44:03Even the scientists who've seen it don't want to publicise this aspect of dolphin behaviour.
44:09It's not that I'm reluctant to tell people about it.
44:11It's just we don't really understand it to put it in a context that is sort of...
44:17Well, to put it in any scientific context at the moment in relation to other questions like aggression and friendliness and social behaviour.
44:26It's just, it's a complete mystery really.
44:33One possible reason perhaps could be that the porpoises interfere with the dolphins' echolocation, disrupting their hunt for fish.
44:42This makes the work of Vincent Yannick of great importance.
44:45He is studying the way in which dolphins use sounds using underwater microphones.
44:50Certain sounds are important in aggressive encounters.
44:57There's one idea that these sounds are actually so high in amplitude that they could hurt the other animal,
45:03and especially the auditory system of the animal.
45:06Dolphins actually perceive sounds through their lower jaw.
45:09And if you see these head-to-head interactions between males they actually are directed head-to-head
45:14and it's possible that they try to focus their sounds towards the lower jaw of the other animal,
45:20but that hasn't been shown in any experiments so far.
45:28Using a multi-channel recorder, Vincent can pick up the sounds from three underwater microphones.
45:34By filming what he sees on the surface, and by working out the distance each dolphin is to the nearest microphone,
45:44he can link the sounds to an individual dolphin.
45:51Previous research methods such as attaching a microphone to the dolphin are too limiting.
45:56This way he can record the use of sound in natural circumstances.
46:00These are clicks and signature whistles.
46:07And two other adults, a bit more to the left,
46:10fourth to the fifth house on the other side.
46:20The left one's now moving more towards the end of the house is there.
46:25Just follow the camera.
46:27Just follow the camera.
46:30These high intensity sounds, called burst pulse sounds, are used in aggressive encounters.
46:35This channel, where the dolphins come in to feed, is ideal for this research,
46:45and the three microphones can be fixed to strategic points.
47:00Listening to the noises that they make is going to be a new revolution in understanding what's going on.
47:10And there's other techniques like using sonar to actually almost take away the problems of visibility
47:15and being able to see what they're doing underwater.
47:17I think we're just teetering on the brink of an understanding.
47:20We've just had the first look.
47:22It's like the edge of an iceberg.
47:24Really understanding how animals develop as well.
47:27How an individual, from growing up as a calf, starts to fit into the social network.
47:31To chart the life successes of individual dolphins will be the next challenge.
47:38What we have gleaned of the private lives of dolphins so far can only tell us a little.
47:44But what we do know is that dolphins have a complex social life,
47:49a network of important and substantial relationships,
47:52and an ability to communicate with each other.
47:55They seem to express that closeness by sexual and physical contacts.
48:00The need to nurture these social bonds explains not dolphin intelligence as such,
48:05but the reason they need big brains.
48:09Very large brains help individuals model their external world.
48:14And one thing an individual might need to model is the distribution of food, for instance.
48:20But an idea that's had a lot of attention lately is that individuals might be modelling their social world.
48:28Like most other animals, the most successful dolphins are those which pass on their genes
48:34to the next generation.
48:36Like Holyfin, the matriarch of Shark Bay with her newborn baby, Nova.
48:41We don't know what sex Nova is yet.
48:44And she was probably born early last night.
48:57Long-lived animals require long research projects.
49:00These three teams of researchers hope to devote the rest of their lives
49:03to their studies.
49:05If they succeed, their work may help us understand all social animals a little better,
49:11including ourselves.
49:33They really move towards social social and social media.
49:35They're like,
49:39they don't have to touch on social media.
49:41They live in terms of social media.
49:43They can benefit from their lives and think of them.
49:45They don't feel that much focus on social media.
49:47They're such a bit of a society.
49:48They're like, you know.
49:50They're like, you know?
49:52They make some sense?
49:54They don't be able to do things.
49:56They can make sure they can make new monkeys.
49:57Next Sunday at 9 p.m.
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