0:00:07 > 0:00:11Millions of us watch clips of animals showing what looks like friendship,
0:00:11 > 0:00:13affection and even love towards each other.
0:00:15 > 0:00:18But what really lies at the heart of these behaviours?
0:00:20 > 0:00:23For centuries, it was thought animals didn't share the same emotions as us.
0:00:25 > 0:00:27But new research is changing all that.
0:00:30 > 0:00:33# Ain't no mountain high enough... #
0:00:33 > 0:00:36I'm Liz Bonnin and I'm going on a worldwide journey...
0:00:37 > 0:00:38Look at that!
0:00:38 > 0:00:43..to find out about these extraordinary animal relationships.
0:00:43 > 0:00:44Hello, my darling!
0:00:44 > 0:00:46These animals, definitely, without a doubt,
0:00:46 > 0:00:48show genuine emotion to each other.
0:00:49 > 0:00:51I think my heart has just broken.
0:00:52 > 0:00:55I'll meet the scientists who have devoted their lives
0:00:55 > 0:00:57to understanding these remarkable bonds.
0:00:58 > 0:01:02There is a commitment there that goes beyond their own life.
0:01:03 > 0:01:06I want to discover if animals are capable of the same emotions
0:01:06 > 0:01:08we experience.
0:01:08 > 0:01:09I can't help laughing!
0:01:12 > 0:01:15And along the way, I'm going to try and find an answer
0:01:15 > 0:01:17to the biggest question of all...
0:01:17 > 0:01:18Do animals love?
0:01:18 > 0:01:22# My love is alive deep down in my heart
0:01:22 > 0:01:24# Although we are miles apart
0:01:24 > 0:01:27# If you ever need a helping hand
0:01:27 > 0:01:31# I'll be there on the double just as fast as I can
0:01:31 > 0:01:35# Don't you know there ain't no mountain high enough... #
0:01:35 > 0:01:39I'm starting my journey in the forests of central Africa.
0:01:48 > 0:01:51I've come to the Democratic Republic of Congo
0:01:51 > 0:01:54because I've heard about a great ape that may just hold the secret
0:01:54 > 0:01:57to long-lasting happy relationships.
0:01:59 > 0:02:00They're called bonobos.
0:02:03 > 0:02:08Bonobos, along with chimpanzees, are our closest living relatives.
0:02:08 > 0:02:12We share 98.6% of our genetic information with them.
0:02:14 > 0:02:18I'm told these close cousins of ours could teach us a thing or two
0:02:18 > 0:02:20about how to build strong bonds.
0:02:21 > 0:02:24It's something every bonobo learns from a very young age.
0:02:32 > 0:02:36Dr Isabel Behncke is one of the few scientists in the world
0:02:36 > 0:02:39who's studied bonobos in the wild.
0:02:39 > 0:02:40You're a curious one!
0:02:41 > 0:02:45I'm meeting her at Lola Ya Bonobo sanctuary in Kinshasa.
0:02:45 > 0:02:46Hello. You must be Liz.
0:02:50 > 0:02:53The infants here are all rescued orphans.
0:02:58 > 0:03:00They've had a difficult start in life
0:03:00 > 0:03:03but each of them has a devoted foster mother,
0:03:03 > 0:03:05who will care for their every need.
0:03:12 > 0:03:16How important is it to match the right maman to the right bonobo?
0:03:16 > 0:03:19Is that really vital for the relationship to thrive?
0:03:19 > 0:03:22It is vital. It is like connecting with a child.
0:03:22 > 0:03:25These women are incredible and very loving.
0:03:25 > 0:03:30And these guys couldn't make it as they do without the mamans.
0:03:30 > 0:03:32It's hard to focus on what you're saying right now.
0:03:32 > 0:03:35- I think my heart has just broken... - I'm OK with that.
0:03:35 > 0:03:38..in two pieces, just looking at this beautiful little thing.
0:03:38 > 0:03:39I'm OK with that. Yeah.
0:03:40 > 0:03:43# Baby love, my baby love
0:03:43 > 0:03:45# I need your love... #
0:03:45 > 0:03:47The mamans, as they're known here,
0:03:47 > 0:03:49will spend the five years
0:03:49 > 0:03:52helping the infants to develop their social skills.
0:03:53 > 0:03:55It's vital they learn how to build bonds,
0:03:55 > 0:03:57so they can eventually be released
0:03:57 > 0:04:00into the sanctuary's larger adult group.
0:04:01 > 0:04:05# Baby love, my baby love... #
0:04:05 > 0:04:08To do that, like any bonobo mother,
0:04:08 > 0:04:10they encourage the little ones to play...
0:04:10 > 0:04:12# My whole life through... #
0:04:12 > 0:04:14..form friendships with each other...
0:04:15 > 0:04:18..and, above all else, they shower them with love.
0:04:19 > 0:04:20# I get this need... #
0:04:21 > 0:04:25Experiencing affection is an important part of their development.
0:04:26 > 0:04:29As adults, bonobos are extremely tactile.
0:04:29 > 0:04:32Touch helps to cement those close relationships.
0:04:34 > 0:04:37The dictum of bonobo society is good relationships,
0:04:37 > 0:04:40strong relationships.
0:04:40 > 0:04:45Another way of looking at bonobos is as the Peter Pan of the great apes.
0:04:45 > 0:04:48Bonobos are the eternally young ape.
0:04:48 > 0:04:52They retain juvenile characteristics, they keep young.
0:04:52 > 0:04:54Bonobos share more with others,
0:04:54 > 0:04:57they show less aggression.
0:04:57 > 0:04:59They are young at heart,
0:04:59 > 0:05:01whatever their age.
0:05:04 > 0:05:06To see that playful side in action,
0:05:06 > 0:05:08Isabel and I are joining the infants
0:05:08 > 0:05:11for their daily bout of rough and tumble.
0:05:14 > 0:05:17Play is a vital building block of bonobo relationships.
0:05:19 > 0:05:22It's so important that they continue to play as adults
0:05:22 > 0:05:25and that's unusual in the animal kingdom.
0:05:32 > 0:05:36But bonobos do something even more surprising.
0:05:38 > 0:05:40To demonstrate that,
0:05:40 > 0:05:42we've found ourselves a little volunteer.
0:05:44 > 0:05:47And in the name of science, we're going to tickle him.
0:05:47 > 0:05:48Tickle, tickle, tickle!
0:05:48 > 0:05:50Tickle, tickle, tickle!
0:05:50 > 0:05:51See that?
0:05:52 > 0:05:54MAKES CHUCKLING NOISES
0:06:00 > 0:06:01Look at her face!
0:06:01 > 0:06:04Scientists have only recently discovered that laughter
0:06:04 > 0:06:06is not unique to humans.
0:06:07 > 0:06:09I can't help laughing!
0:06:10 > 0:06:14Just like us, for bonobos, laughter is a form of communication.
0:06:16 > 0:06:18And what laughter is doing,
0:06:18 > 0:06:21it's a signal that tells other individuals
0:06:21 > 0:06:23I want to continue playing with you.
0:06:23 > 0:06:25I want to continue interacting with you.
0:06:25 > 0:06:27In humans, for example,
0:06:27 > 0:06:31conversations that have laughter last longer.
0:06:31 > 0:06:36If we share a bout of laughter, we feel bonded, we feel relaxed.
0:06:36 > 0:06:39It really is a booster to that internal motivation,
0:06:39 > 0:06:42like, yeah, this is wonderful, let's keep doing it.
0:06:45 > 0:06:49Play is a safe way to test the boundaries of a relationship
0:06:49 > 0:06:53and that helps to build an incredibly tolerant society.
0:06:58 > 0:06:59Juvenile!
0:07:00 > 0:07:01Oh, my God!
0:07:05 > 0:07:06We lost the boom!
0:07:07 > 0:07:09That's a naughty bonobo!
0:07:12 > 0:07:15In the wild, play makes all the difference.
0:07:21 > 0:07:24While chimps can be extremely aggressive towards each other,
0:07:24 > 0:07:27bonobos generally seem to get along.
0:07:35 > 0:07:37We've never observed lethal aggression.
0:07:37 > 0:07:40We've never observed a bonobo kill another bonobo.
0:07:40 > 0:07:42And that is very special, that's very different,
0:07:42 > 0:07:44because that happens in chimpanzees
0:07:44 > 0:07:46and that happens in other primates as well.
0:07:51 > 0:07:55Another thing that makes bonobos different from every other great ape
0:07:55 > 0:07:58is that their society is run by females.
0:08:01 > 0:08:03Their approach to leadership involves a strict
0:08:03 > 0:08:06"make love, not war" policy.
0:08:11 > 0:08:14Adult bonobos have very open relationships,
0:08:14 > 0:08:16which involve a lot of sex.
0:08:19 > 0:08:21It's a win-win situation.
0:08:22 > 0:08:25Males don't have to fight for female attention.
0:08:25 > 0:08:29And with so much physical contact, everyone is much more relaxed.
0:08:34 > 0:08:36But is there any more to it than that?
0:08:41 > 0:08:44Can we go as far as saying that the bonds involve love?
0:08:45 > 0:08:47It depends what you mean by love.
0:08:48 > 0:08:53If you mean human-like, romantic, monogamous love, no.
0:08:53 > 0:08:55I would say no.
0:08:55 > 0:08:58Now, if you mean the core of love
0:08:58 > 0:09:00which, to me, is about protection,
0:09:00 > 0:09:05and is about the physiological machinery of love,
0:09:05 > 0:09:08I don't see why we wouldn't call that love.
0:09:10 > 0:09:12Love is ancient.
0:09:12 > 0:09:16Love was born approximately 250 million years ago
0:09:16 > 0:09:20in a very small primitive mammal and her kid.
0:09:21 > 0:09:22Mother-infant bond.
0:09:23 > 0:09:25Something so old
0:09:25 > 0:09:29is likely to remain and prevail all the mammalian species.
0:09:30 > 0:09:32Especially great apes, who are highly-bonded.
0:09:36 > 0:09:39Witnessing such a harmonious way of life
0:09:39 > 0:09:42in an animal that is our closest cousin,
0:09:42 > 0:09:43does make you stop and think.
0:09:45 > 0:09:47By building strong relationships,
0:09:47 > 0:09:51they've ended up with one of the most peaceful societies on the planet.
0:09:53 > 0:09:58While it's the females who can take much of the credit in bonobo society,
0:09:58 > 0:10:01for other animals, the success of a group is centred around
0:10:01 > 0:10:03the relationship of just one couple.
0:10:09 > 0:10:14I've travelled 2,000 miles south of the Congo to meet one such pair.
0:10:14 > 0:10:17They live here in South Africa's Kwazulu-Natal.
0:10:19 > 0:10:23The couple I've come to see are only just starting out.
0:10:26 > 0:10:28I want to find out what it will take
0:10:28 > 0:10:31to make their relationship a success.
0:10:32 > 0:10:36Axel Primmer and Taryn Gilroy have been tracking this pair
0:10:36 > 0:10:37since they first got together.
0:10:40 > 0:10:41Straight, Axel!
0:10:44 > 0:10:47Right in the road in front of us. Yeah. I can see them all, yeah.
0:10:47 > 0:10:49Oh, well, there you have it...
0:10:50 > 0:10:51Look at that!
0:10:51 > 0:10:55Sorry, I just can't get over what we're seeing here, we're so lucky.
0:11:01 > 0:11:03So, there they are.
0:11:03 > 0:11:06Feather, followed closely by Aladdin,
0:11:06 > 0:11:12the alpha pair of this eight-strong pack of African wild dogs.
0:11:14 > 0:11:18To see African wild dogs in the flesh is a real privilege.
0:11:19 > 0:11:22It's thought there may only be 3,000 left in the wild,
0:11:22 > 0:11:25making them one of the most endangered mammals in Africa.
0:11:31 > 0:11:34Aladdin, the alpha male, wears the radio collar.
0:11:36 > 0:11:41But it really is quiet fascinating to watch the alpha pair always together.
0:11:42 > 0:11:43Always together.
0:11:43 > 0:11:47The male is constantly tailing behind her, wherever she goes.
0:11:48 > 0:11:52Aladdin and Feather have only been together for four months,
0:11:52 > 0:11:54but they're already off to a flying start.
0:11:55 > 0:11:56Feather is visibly pregnant.
0:11:58 > 0:12:00But even though he has now done the job,
0:12:00 > 0:12:03she is pregnant with his pups,
0:12:03 > 0:12:05he doesn't leave her side for one minute.
0:12:06 > 0:12:13# I've got sunshine on a cloudy day
0:12:16 > 0:12:18# When it's cold outside... #
0:12:18 > 0:12:22It's unusual for an alpha male to be so attentive at this stage.
0:12:23 > 0:12:26Aladdin seems to be a particularly devoted partner.
0:12:26 > 0:12:29# I guess you'd say
0:12:29 > 0:12:33# What can make me feel this way? #
0:12:33 > 0:12:37Taryn has been monitoring Feather and Aladdin's progress from the start.
0:12:38 > 0:12:41So, tell me about how Aladdin and Feather behave with each other,
0:12:41 > 0:12:42as the alpha pair.
0:12:42 > 0:12:46We've often seen him with his chin resting on her rear end
0:12:46 > 0:12:48and just following her around.
0:12:48 > 0:12:52And she's been observed sleeping with his paw on her at night.
0:12:52 > 0:12:54It's typical. It's what we call mate-guarding behaviour.
0:12:55 > 0:12:57He's looking after her,
0:12:57 > 0:13:00he's making sure that she's fit and healthy.
0:13:00 > 0:13:03Once she's pregnant, he continues to follow her.
0:13:03 > 0:13:06Even though he's already done his job and fathered her litter.
0:13:06 > 0:13:09And I think that's his way of ensuring that his litter of pups
0:13:09 > 0:13:11survives and is healthy.
0:13:13 > 0:13:15Aladdin and Feather look like a solid couple.
0:13:17 > 0:13:21And that's good news for everyone else in the group
0:13:21 > 0:13:22because, as the alpha pair,
0:13:22 > 0:13:25it's their job to provide the pack with new pups.
0:13:27 > 0:13:28So, is that it?
0:13:28 > 0:13:32Are they completely established and their roles are determined
0:13:32 > 0:13:34and everything's hunky-dory with the whole pack?
0:13:34 > 0:13:36Well, so far, so good.
0:13:36 > 0:13:38The key will be how successful they are
0:13:38 > 0:13:40at raising that litter of pups as a pack.
0:13:41 > 0:13:46The success of a pack always depends on their reproductive success.
0:13:46 > 0:13:51So, how well they work together to successfully rear their young.
0:13:51 > 0:13:52So, they're not home free?
0:13:52 > 0:13:54Not at all. Not at all.
0:13:54 > 0:13:56So, whenever you get a new alpha pair,
0:13:56 > 0:13:57it doesn't mean anything
0:13:57 > 0:14:00until they've successfully reared their first litter?
0:14:00 > 0:14:02- Their first litter. - Oh, gosh, no pressure.
0:14:04 > 0:14:06Fortunately, for Aladdin and Feather,
0:14:06 > 0:14:09the rest of the group will be there to lend a helping hand.
0:14:10 > 0:14:12The other adult females are Feather's sisters
0:14:12 > 0:14:15and the males come from different packs.
0:14:17 > 0:14:19Here come the rest behind us.
0:14:20 > 0:14:21It's one big, happy family,
0:14:21 > 0:14:23where everyone pitches in.
0:14:27 > 0:14:29Feather's older sister, Batty,
0:14:29 > 0:14:31is the lead hunter.
0:14:32 > 0:14:36By sharing the workload, the pack runs like a well-oiled machine.
0:14:36 > 0:14:38The wildebeest are chasing here.
0:14:38 > 0:14:39He's gone in. He's gone in.
0:14:39 > 0:14:42The others have... Oh...!
0:14:42 > 0:14:43Well, most of the time.
0:14:45 > 0:14:49So, you've got wildebeest chasing the wild dogs.
0:14:50 > 0:14:51What's wrong with that picture?
0:14:53 > 0:14:56When Aladdin and Feather's pups are born,
0:14:56 > 0:14:58everyone will help to feed and protect them.
0:15:01 > 0:15:03Here, bigger families do better.
0:15:06 > 0:15:08If the pack doesn't grow in size,
0:15:08 > 0:15:11they'll struggle to defend themselves and their territory.
0:15:16 > 0:15:19The survival of this endangered species
0:15:19 > 0:15:23rests on the shoulders of couples like Feather and Aladdin.
0:15:27 > 0:15:31And having seen how close they are, you can't help but root for them.
0:15:38 > 0:15:41Relying on your nearest and dearest to help raise your young
0:15:41 > 0:15:45is a tactic used by many other couples in the animal kingdom.
0:15:46 > 0:15:49So, how does an alpha pair make sure it's their young
0:15:49 > 0:15:50that get all the attention?
0:15:51 > 0:15:54To answer that, I'm going to the Isle of Wight,
0:15:54 > 0:15:56to meet an incredibly rare primate.
0:16:07 > 0:16:09So, these little monkeys,
0:16:09 > 0:16:11weighing no more than half a kilo,
0:16:11 > 0:16:13are cotton-top tamarins,
0:16:13 > 0:16:15for obvious reasons.
0:16:16 > 0:16:18And they're critically endangered.
0:16:18 > 0:16:20The only place they can still be found in the wild
0:16:20 > 0:16:22is a tiny part of Columbia.
0:16:28 > 0:16:33The leaders of this boisterous bunch are a couple called Carlos and Maria.
0:16:35 > 0:16:39They've been together five years and have five offspring,
0:16:39 > 0:16:41the latest of which is just a few months old.
0:16:50 > 0:16:54Tierney Smith has been caring for this family for the last year.
0:17:04 > 0:17:06What are Carlos and Maria like as a couple?
0:17:06 > 0:17:08Like most tamarins,
0:17:08 > 0:17:10they do have that really strong bond with each other.
0:17:11 > 0:17:13They are both quite a dominant pair
0:17:13 > 0:17:16and it's nice to see them work as a team
0:17:16 > 0:17:18to kind of keep their family in check.
0:17:18 > 0:17:20And do Maria and Carlos have
0:17:20 > 0:17:23very specific, like, personalities, anyway, of their own?
0:17:23 > 0:17:26He's more expressive, like, with his face.
0:17:26 > 0:17:27He'll frown at new things.
0:17:27 > 0:17:30He'll wade in and he'll want to check everything out.
0:17:30 > 0:17:33Maria, she'll check things out from afar.
0:17:33 > 0:17:35She'll let her family go in
0:17:35 > 0:17:39and she likes to survey the area, just check there's no threats
0:17:39 > 0:17:41and, if there is, she's in a position to call to them.
0:17:43 > 0:17:46Family is hugely important to these little monkeys.
0:17:48 > 0:17:51In the wild, raising young is so demanding
0:17:51 > 0:17:53that, just like African wild dogs,
0:17:53 > 0:17:54the whole family has to pitch in.
0:17:56 > 0:18:00And tamarins have a very effective way of making sure
0:18:00 > 0:18:02they get the help they need...
0:18:02 > 0:18:04And it's all down to some pretty clever tactics
0:18:04 > 0:18:06on the dominant female's part.
0:18:08 > 0:18:10When Maria is ready to get pregnant,
0:18:10 > 0:18:12she'll scent mark more than anyone else.
0:18:13 > 0:18:15And that's because hormones in her urine
0:18:15 > 0:18:17can temporarily stop the other females in the group
0:18:17 > 0:18:19from getting pregnant.
0:18:23 > 0:18:26This ensures that there are plenty of helpers when her babies are born.
0:18:31 > 0:18:33But it's not all about the little ones.
0:18:33 > 0:18:35Tamarin couples are extremely close
0:18:35 > 0:18:38and once again, this is very much related to hormones.
0:18:41 > 0:18:45Carlos and Maria spend a lot of time grooming and cuddling
0:18:45 > 0:18:48and that's the secret of their strong relationship.
0:18:49 > 0:18:51Scientists have discovered
0:18:51 > 0:18:54that tamarin pairs who show a lot of affection towards each other
0:18:54 > 0:18:57have higher levels of oxytocin,
0:18:57 > 0:18:58also known as the love hormone.
0:19:00 > 0:19:03It's the same hormone that helps human couples to bond
0:19:03 > 0:19:06and it's found in many other mammals.
0:19:07 > 0:19:10# Oh, my darling babe, I
0:19:12 > 0:19:14# I can't get enough of your love, babe... #
0:19:17 > 0:19:21Oxytocin is nature's way of helping us to stay together,
0:19:21 > 0:19:24reinforcing the connection we have with our partner.
0:19:26 > 0:19:27# My darling, I
0:19:29 > 0:19:31# Can't get enough of your love, babe
0:19:32 > 0:19:33# Oh, no, babe... #
0:19:34 > 0:19:36Showing affection to your partner
0:19:36 > 0:19:39is an important part of any relationship.
0:19:42 > 0:19:45# Oh, my darling babe, I... #
0:19:46 > 0:19:47But, when it comes to kissing,
0:19:47 > 0:19:49there's a lot more going on than you might think.
0:19:52 > 0:19:56I've travelled to Colorado to meet Dr Jennifer Verdolin.
0:19:59 > 0:20:02Jennifer has spent years studying North American prairie dogs.
0:20:04 > 0:20:07And there's one behaviour she's fascinated by.
0:20:11 > 0:20:13She's been trying to figure out
0:20:13 > 0:20:16why they spend so much time locking lips.
0:20:18 > 0:20:19They do this a lot.
0:20:19 > 0:20:22Almost inevitably, when two prairie dogs come together,
0:20:22 > 0:20:23they will greet kiss.
0:20:23 > 0:20:26It will happen between males and males,
0:20:26 > 0:20:27females and other females,
0:20:27 > 0:20:29mothers and their offspring.
0:20:29 > 0:20:31In saliva, you find all kinds of chemicals.
0:20:31 > 0:20:35You find pheromones, you get information about hormone levels.
0:20:35 > 0:20:37And so, between males, they could be evaluating
0:20:37 > 0:20:40the testosterone load of another male.
0:20:40 > 0:20:42And between males and females,
0:20:42 > 0:20:44the males might be able to detect whether or not
0:20:44 > 0:20:46a female is receptive to mating.
0:20:46 > 0:20:49So, it's not the similar kissing behaviour
0:20:49 > 0:20:52that humans exhibit when they kiss.
0:20:52 > 0:20:54Are there any similarities at all?
0:20:54 > 0:20:56There are. I mean, a lot of times,
0:20:56 > 0:20:59we think about our kissing behaviour in terms of giving affection.
0:20:59 > 0:21:00And certainly, it does.
0:21:00 > 0:21:04But, there's a whole cascade of chemicals that happen when we kiss
0:21:04 > 0:21:07and it's thought that we're getting information
0:21:07 > 0:21:11about how good a quality mate this particular individual is
0:21:11 > 0:21:12when we kiss.
0:21:12 > 0:21:16And do we know how this kissing behaviour might have evolved?
0:21:16 > 0:21:19One idea is that it might have evolved as a way
0:21:19 > 0:21:23for mothers and offspring to share information about what to eat.
0:21:23 > 0:21:25So, passing food from mother to offspring.
0:21:25 > 0:21:27And then, like any behaviour,
0:21:27 > 0:21:29it can become adapted to serve different functions.
0:21:29 > 0:21:31So, not only for learning what to eat,
0:21:31 > 0:21:33as it might also happen in prairie dogs,
0:21:33 > 0:21:36but information, or bonding, maintaining those bonds,
0:21:36 > 0:21:39not just between mother and infant, but between pair bonds.
0:21:40 > 0:21:43For us, kissing is such an intimate thing.
0:21:43 > 0:21:47And what's remarkable is that it has so many different purposes.
0:21:52 > 0:21:54But what I really want to find out
0:21:54 > 0:21:58is if there's an emotional side to animal relationships.
0:22:02 > 0:22:04I am travelling deep into the Austrian Alps
0:22:04 > 0:22:07to meet a couple who seemed destined to be together.
0:22:14 > 0:22:17Dr Didone Frigerio is a biologist
0:22:17 > 0:22:20from the world-famous Konrad Lorenz research group.
0:22:21 > 0:22:23They've been studying this flock of greylag geese
0:22:23 > 0:22:25for more than 40 years.
0:22:27 > 0:22:29Greylag geese are known for having
0:22:29 > 0:22:32particularly strong long-term relationships.
0:22:32 > 0:22:34But I'm here to find out about a pair
0:22:34 > 0:22:36who really captured Didone's heart.
0:22:41 > 0:22:43Their names are Tarek and Judith.
0:22:43 > 0:22:45And they met eight years ago.
0:22:48 > 0:22:53They were together for three years without being success.
0:22:53 > 0:22:57That means they didn't have goslings together.
0:22:57 > 0:23:00So, is that a bit unusual that they would stay together for three years,
0:23:00 > 0:23:03even though they didn't rear young together?
0:23:03 > 0:23:04No, is not unusual.
0:23:04 > 0:23:08There are many pairs within the flock, who never reproduce.
0:23:08 > 0:23:09And yet, they stay together?
0:23:09 > 0:23:11Yes, they stay together for years.
0:23:11 > 0:23:13And then what happened?
0:23:13 > 0:23:16And then it was winter, it was January
0:23:16 > 0:23:19and there came a storm
0:23:19 > 0:23:22and Judith was gone.
0:23:22 > 0:23:24She got lost in the storm.
0:23:27 > 0:23:31Judith's sudden disappearance meant Tarek was now alone.
0:23:34 > 0:23:36When a mate are losing their partner,
0:23:36 > 0:23:38they are laying around a lot,
0:23:38 > 0:23:39they are feeding less.
0:23:39 > 0:23:42They are not joining the social life of the flock.
0:23:42 > 0:23:45Yeah, I would say they are quite depressed.
0:23:46 > 0:23:49Without a partner, Tarek was vulnerable.
0:23:51 > 0:23:55You have to imagine a pair is a social unit.
0:23:55 > 0:23:57And they are supporting each other.
0:23:57 > 0:24:00And when they are left alone, for sure, they are an easy target.
0:24:00 > 0:24:04And everybody else in the flock is attacking him,
0:24:04 > 0:24:06biting him, and chasing him.
0:24:09 > 0:24:11Having been alone for months,
0:24:11 > 0:24:14Tarek eventually began a new relationship
0:24:14 > 0:24:16with another female in the flock.
0:24:19 > 0:24:21His luck had finally turned
0:24:21 > 0:24:24and Tarek was back to his old self.
0:24:25 > 0:24:28The breeding season was only a few weeks away
0:24:28 > 0:24:31and there was every hope he would finally start a family
0:24:31 > 0:24:32with his new partner.
0:24:32 > 0:24:34But fate had other plans for Tarek.
0:24:37 > 0:24:41Almost a year after they were tragically separated by a storm,
0:24:41 > 0:24:43Judith returned.
0:24:43 > 0:24:46And Tarek's reaction was quite extraordinary.
0:24:51 > 0:24:54Tarek was going back to Judith.
0:24:54 > 0:24:57That's quiet incredible, isn't it? Because...
0:24:57 > 0:24:59- It's hard.- Like you... It's hard.
0:24:59 > 0:25:02It's hard. Well, it depends from which point of view.
0:25:02 > 0:25:05But it just goes to show, as you say, life goes on.
0:25:05 > 0:25:10Biology is such that Tarek needs to find a new mate.
0:25:10 > 0:25:13But something in Tarek
0:25:13 > 0:25:18made him want to be with Judith above his new mate.
0:25:18 > 0:25:20What do you think was going on there?
0:25:20 > 0:25:26Yeah, I think it is experience and how strong the pair bond was.
0:25:26 > 0:25:30They were a good pair. They were good match.
0:25:30 > 0:25:32It's fascinating to think about it.
0:25:32 > 0:25:33And whatever...
0:25:33 > 0:25:36You know, because we can never get into the head of a goose,
0:25:36 > 0:25:38to know what Tarek was thinking.
0:25:38 > 0:25:39What's absolutely clear
0:25:39 > 0:25:42- is that the strength of the bond he had with Judith...- Yes.
0:25:42 > 0:25:46..was strong enough for him to go, "She's back. She's the one.
0:25:46 > 0:25:47"I'm going back to her."
0:25:47 > 0:25:50- Yes, I think so. - Love that story.
0:25:52 > 0:25:54So... So, this is them?
0:25:54 > 0:25:56Yeah, this is them.
0:25:56 > 0:25:59As you can see on the right, the bigger one is Tarek.
0:25:59 > 0:26:00So, Tarek, Judith...
0:26:02 > 0:26:03And four goslings.
0:26:04 > 0:26:06The one here on the right is Tarek.
0:26:06 > 0:26:09And you can see he is watching and keeping everything under control.
0:26:09 > 0:26:12And this is the second year they've bred successfully?
0:26:12 > 0:26:15- And actually reared successfully, more to the point?- Yes. Yes.
0:26:15 > 0:26:18It was totally worth getting back together, wasn't it?
0:26:18 > 0:26:19Yeah, of course.
0:26:21 > 0:26:25The story of Tarek and Judith really is heart-warming
0:26:25 > 0:26:27and raises many intriguing questions.
0:26:28 > 0:26:30If it was simply a matter of survival,
0:26:30 > 0:26:33then why didn't Tarek just stay with his new partner?
0:26:36 > 0:26:39Why was he so compelled to be with Judith?
0:26:40 > 0:26:43Could it possibly have been love?
0:26:46 > 0:26:49Professor Kurt Kotrschal from the University of Vienna
0:26:49 > 0:26:52has spent decades studying the long-term bonds
0:26:52 > 0:26:53between greylag geese.
0:26:55 > 0:26:58I want to find out if he thinks there's an emotional side
0:26:58 > 0:27:01to Tarek and Judith's relationship.
0:27:03 > 0:27:06Do geese have emotions, then?
0:27:07 > 0:27:09Well, it's a difficult thing to know
0:27:09 > 0:27:10because, as a scientist,
0:27:10 > 0:27:13I'm not supposed to project something into a goose.
0:27:13 > 0:27:17But what we know is that kind of six basic emotions
0:27:17 > 0:27:20are common to mammals, to birds.
0:27:22 > 0:27:25Anger, fear, falling in love,
0:27:25 > 0:27:27sexual arousal, play.
0:27:27 > 0:27:30And we have these kind of erm...
0:27:30 > 0:27:33A pedative system, being interested in something.
0:27:33 > 0:27:35That's one of the basic emotional systems.
0:27:35 > 0:27:40I didn't realise that falling in love was considered a basic emotion.
0:27:40 > 0:27:42I thought that was quite a complex one
0:27:42 > 0:27:45and one that most people are loath to draw analogies about
0:27:45 > 0:27:47when it comes to humans and other animals.
0:27:47 > 0:27:50How controversial was it to come up with this?
0:27:50 > 0:27:53And how long has it been since it's been pretty much accepted
0:27:53 > 0:27:55within the scientific community?
0:27:55 > 0:27:59People didn't want to hear about it because they liked to be special.
0:27:59 > 0:28:04There was this deep trench generated over the centuries.
0:28:04 > 0:28:06And now we know.
0:28:06 > 0:28:10The last ten, 20 years we have produced increasing evidence
0:28:10 > 0:28:12that the trench between humans and animals
0:28:12 > 0:28:15is not as deep as many people would want it to be.
0:28:16 > 0:28:20The part of the brain responsible for the basic mechanisms
0:28:20 > 0:28:22are the same in humans and geese.
0:28:22 > 0:28:24The hormones involved are the same.
0:28:24 > 0:28:26The behaviour we see is the same.
0:28:26 > 0:28:29So, there is a lot of parallels.
0:28:29 > 0:28:32What we cannot say, of course, is how they are feeling.
0:28:32 > 0:28:36Whether the human feeling of falling in love
0:28:36 > 0:28:38is the same that the goose feeling of falling in love.
0:28:38 > 0:28:41But it's not unlikely that it's really the same.
0:28:45 > 0:28:48The research Kurt and the rest of his colleagues are conducting
0:28:48 > 0:28:51is changing how we see animal relationships.
0:28:53 > 0:28:56It proves that, for some animals,
0:28:56 > 0:28:58it's not just about finding any partner.
0:28:58 > 0:29:01For Tarek, Judith really was "the one".
0:29:03 > 0:29:06And they've gone on to successfully raise a family together.
0:29:08 > 0:29:10Many animals form long-term relationships
0:29:10 > 0:29:12to raise the next generation.
0:29:12 > 0:29:14# Just the two of us
0:29:15 > 0:29:18# We can make it if we try
0:29:18 > 0:29:19# Just the two of us
0:29:20 > 0:29:21# Just the two of us
0:29:22 > 0:29:24# Just the two of us
0:29:25 > 0:29:27# Living in castles in the sky
0:29:27 > 0:29:31# Just the two of us, you an I... #
0:29:31 > 0:29:34But perhaps one of the most extraordinary new discoveries
0:29:34 > 0:29:38is that it seems there's much more to some animal relationships
0:29:38 > 0:29:39than just rearing young.
0:29:42 > 0:29:45I've travelled to Germany, to Bremerhaven Zoo,
0:29:45 > 0:29:49to meet one pair who have become something of a celebrity couple.
0:29:56 > 0:29:58They're called Dotty and Z
0:29:58 > 0:30:00and they're Humboldt penguins.
0:30:03 > 0:30:06They've been together for over a decade.
0:30:06 > 0:30:09And right from the very start, Dotty and Z have been inseparable.
0:30:13 > 0:30:17To all intents and purposes, they are the model penguin couple.
0:30:20 > 0:30:22In the ten years that they've been together,
0:30:22 > 0:30:25the bond between Dotty and Z is as strong as ever,
0:30:25 > 0:30:28but they have suffered one major setback.
0:30:28 > 0:30:31And that is they've never been able to produce a chick of their own.
0:30:32 > 0:30:36In 2005, the zoo discovered why this devoted pair
0:30:36 > 0:30:39hadn't had any luck starting a family.
0:30:40 > 0:30:46# Nothing you can do can tear me away from my guy... #
0:30:47 > 0:30:52A DNA test revealed that both Dotty and Z were males.
0:30:52 > 0:30:54# From my guy... #
0:30:54 > 0:30:57And what's more, they weren't alone.
0:30:58 > 0:31:01Of the ten penguin pairs at the zoo,
0:31:01 > 0:31:03there were three same-sex male couples.
0:31:05 > 0:31:09Vet Joachim Schoene has watched Dotty and Z's relationship unfold
0:31:09 > 0:31:11over the last decade.
0:31:13 > 0:31:16What happened when you figured out, oh, hang on, OK, they're males?
0:31:16 > 0:31:17What did you do then?
0:31:17 > 0:31:20This is one of the most endangered penguin species in the world.
0:31:20 > 0:31:23There may only be 2,000 birds left in the wild.
0:31:23 > 0:31:26So, just to give them an option to breed,
0:31:26 > 0:31:30we flew in six Swedish Humboldt penguins
0:31:30 > 0:31:31from the zoo of Kolmarden.
0:31:31 > 0:31:33And did they breed?
0:31:33 > 0:31:35Erm...no. They didn't.
0:31:35 > 0:31:38So, the three gay couples stayed together.
0:31:38 > 0:31:43Yeah. Showing us that those are really strong relationships.
0:31:44 > 0:31:47Although they could never produce a chick of their own,
0:31:47 > 0:31:50the parenting instinct between Dotty and Z
0:31:50 > 0:31:51remained incredibly strong.
0:31:51 > 0:31:55Each year, they built a nest, like all the other couples.
0:31:59 > 0:32:03But in 2009, the zoo gave Dotty and Z an unexpected opportunity.
0:32:05 > 0:32:08A rejected egg from another couple was placed in their nest.
0:32:10 > 0:32:14Between them, Dotty and Z shared the responsibly
0:32:14 > 0:32:15of incubating the egg.
0:32:15 > 0:32:18How did Z and Dotty fair when the chick hatched?
0:32:19 > 0:32:21They behaved like good fathers.
0:32:21 > 0:32:24They were taking care well of the little chick,
0:32:24 > 0:32:27sharing the feeding work.
0:32:27 > 0:32:32And, yeah, they behaved the same way as if they were heterosexual.
0:32:32 > 0:32:35Did you have any doubts that Dotty and Z would be good parents?
0:32:35 > 0:32:36We were quite confident,
0:32:36 > 0:32:39because there are some examples from other zoos in the world.
0:32:39 > 0:32:43So, we were quite excited about what would happen
0:32:43 > 0:32:45in our little colony here.
0:32:45 > 0:32:48And for us, yeah, and for the birds, it was quiet a success story.
0:32:48 > 0:32:51# Like a stamp to a letter, like birds of a feather
0:32:51 > 0:32:53# We stick together... #
0:32:54 > 0:32:57Z and Dotty's relationship is fascinating.
0:32:57 > 0:32:59And it's certainly challenging our understanding
0:32:59 > 0:33:03of the nature and benefits of pair bonds.
0:33:03 > 0:33:04But it also begs the question...
0:33:04 > 0:33:07How common is this in the animal kingdom?
0:33:10 > 0:33:12To find out more about Dotty and Z's relationship,
0:33:12 > 0:33:16I'm meeting Dr Qazi Rahman from King's College university.
0:33:19 > 0:33:21I mean, Dotty and Z are a great example, aren't they?
0:33:21 > 0:33:24Because what I find most fascinating about their story
0:33:24 > 0:33:25is that they may have gotten together
0:33:25 > 0:33:27because there weren't any females around.
0:33:27 > 0:33:30But, when they were introduced to females, they were like,
0:33:30 > 0:33:32"No, we're happy together and we don't want to breed with a female."
0:33:32 > 0:33:35Yes. And I think, for me, that's really good evidence
0:33:35 > 0:33:38that this same-sex pair bond is solid and it's stable.
0:33:39 > 0:33:43Same-sex bonds have the same quality and same intensity
0:33:43 > 0:33:45as heterosexual bonds do
0:33:45 > 0:33:47in the animals that have been studied so far.
0:33:47 > 0:33:49So, we see same-sex behaviour
0:33:49 > 0:33:52both in animals in captivity and in the wild.
0:33:52 > 0:33:54And in fact, we now think we underestimate
0:33:54 > 0:33:56same-sex behaviour in the wild.
0:33:59 > 0:34:01One fascinating example of this
0:34:01 > 0:34:04can be found on the Island of Oahu in Hawaii.
0:34:09 > 0:34:13Scientists have been monitoring Laysan albatrosses here for decades.
0:34:14 > 0:34:17But it wasn't until 2008 that they discovered that
0:34:17 > 0:34:21almost a third of their couples were same-sex female pairs.
0:34:24 > 0:34:27One pair had been together for 19 years.
0:34:35 > 0:34:39Researchers believe the high levels of female pairs on this island
0:34:39 > 0:34:41is due to a shortage of males.
0:34:48 > 0:34:53Certainly, a shortage of one sex is associated with same-sex pairings
0:34:53 > 0:34:54in some of these species.
0:34:54 > 0:34:58But, equally, there is evidence that these same-sex pairings
0:34:58 > 0:34:59arise naturally.
0:34:59 > 0:35:01It's as if it's a preference.
0:35:01 > 0:35:04You might even say an inborn preference in some of these species.
0:35:06 > 0:35:08The thing to remember is that there are benefits
0:35:08 > 0:35:11other than reproduction, in an evolutionary sense.
0:35:11 > 0:35:14And I think the really critical point here is that
0:35:14 > 0:35:16there are advantages to survival
0:35:16 > 0:35:18from being in a monogamous partnership.
0:35:20 > 0:35:23Scientists are discovering that, for animals who mate for life,
0:35:23 > 0:35:25having a partner, same-sex or otherwise,
0:35:25 > 0:35:28can improve the quality of your life.
0:35:29 > 0:35:31It can reduce your stress levels,
0:35:31 > 0:35:33help you to protect your home
0:35:33 > 0:35:36and can even increase your life expectancy.
0:35:39 > 0:35:42Which is why same-sex relationships occur in nature
0:35:42 > 0:35:44a lot more often than you might think.
0:35:45 > 0:35:47# I'm coming up
0:35:47 > 0:35:48# Coming
0:35:48 > 0:35:50# I want the world to know
0:35:50 > 0:35:52# That you love me so... #
0:35:52 > 0:35:57In the last decade, scientists have discovered same-sex pairings
0:35:57 > 0:36:00in almost 450 different species.
0:36:00 > 0:36:01# Got to let it show... #
0:36:04 > 0:36:07I'm finding out that relationships in the animal kingdom
0:36:07 > 0:36:12are far more complex and diverse than we could possibly have imagined.
0:36:13 > 0:36:16But, for many animals, we humans included,
0:36:16 > 0:36:19some of the most important relationships we have
0:36:19 > 0:36:21are not necessarily with our partners.
0:36:24 > 0:36:28Sometimes, it's our friends who we need to rely on most
0:36:28 > 0:36:32and I've heard of a friendship between two African elephants
0:36:32 > 0:36:33that I want to investigate.
0:36:37 > 0:36:42I've travelled to Thula Thula, a reserve in South Africa's Zululand.
0:36:48 > 0:36:52David Bozas has known the elephants here for the over a decade
0:36:52 > 0:36:55and has played a very important role in their lives.
0:36:57 > 0:36:58Do you see them?
0:37:02 > 0:37:05Look at that, they're right there in the open.
0:37:05 > 0:37:06That's a stroke of luck.
0:37:08 > 0:37:09Fantastic.
0:37:11 > 0:37:15The two females I've come see are incredibly close.
0:37:16 > 0:37:18The one on the left is called Frankie.
0:37:18 > 0:37:20And the smaller of the two is called ET.
0:37:23 > 0:37:25Most herds are made up of family members.
0:37:27 > 0:37:30What's unusual about ET and Frankie's relationship
0:37:30 > 0:37:32is that they aren't even related.
0:37:36 > 0:37:40I'm here to find out how that friendship saved ET's life.
0:37:42 > 0:37:44Their story begins 15 years ago,
0:37:44 > 0:37:48when Frankie and the rest of her family were brought to this reserve.
0:37:49 > 0:37:51It was a difficult time in the herd's life.
0:37:53 > 0:37:58When they arrived, it was visible they were heavily traumatised.
0:37:59 > 0:38:02They were aggressive, they were violent.
0:38:02 > 0:38:03And when it came to light
0:38:03 > 0:38:06the history of what had happened to these animals,
0:38:06 > 0:38:07it became clear why they were like that.
0:38:09 > 0:38:12The reason Frankie and her family were so stressed
0:38:12 > 0:38:15is that they were the victims of a brutal culling.
0:38:18 > 0:38:22Hunters had shot and killed several members of their herd.
0:38:24 > 0:38:27Frankie's close-knit family had been fractured
0:38:27 > 0:38:30in ways they might never fully recover from.
0:38:40 > 0:38:42Fear quickly turned to aggression
0:38:42 > 0:38:45and, soon, the herd had earned themselves a reputation
0:38:45 > 0:38:47for being a danger to humans.
0:38:50 > 0:38:52We had to recognise
0:38:52 > 0:38:55that we were the reason these animals were like this.
0:38:56 > 0:39:00Witnessing the killing of family members had left them traumatised.
0:39:01 > 0:39:05These animals had lost complete trust, and for good reason.
0:39:05 > 0:39:06They look at a human
0:39:06 > 0:39:08and they just go back to what happened to their family?
0:39:08 > 0:39:12They see destruction, they see turmoil, they see loss.
0:39:15 > 0:39:18The underlying thing was, we had to gain these animals' trust back.
0:39:20 > 0:39:22ELEPHANT TRUMPETS
0:39:26 > 0:39:29David wasn't alone in this enormous task.
0:39:29 > 0:39:32He was working alongside the late Lawrence Anthony.
0:39:33 > 0:39:35For their own safety,
0:39:35 > 0:39:38when the elephants arrived, they had to be corralled into an enclosure.
0:39:40 > 0:39:44David and Lawrence camped out next to the herd day and night
0:39:44 > 0:39:45to gain their trust.
0:39:46 > 0:39:49You always had the sense of
0:39:49 > 0:39:51aggression and animosity from the herd.
0:39:51 > 0:39:53I mean, the atmosphere was very thick.
0:39:55 > 0:39:59But it was Frankie who would prove the most difficult to win over.
0:39:59 > 0:40:01She was the principal aggressor.
0:40:01 > 0:40:04I mean, she just wanted to get hold of us and flatten us
0:40:04 > 0:40:05and get rid of us.
0:40:05 > 0:40:07FRANKIE TRUMPETS
0:40:07 > 0:40:09Weeks passed with no improvement.
0:40:10 > 0:40:15But David and Lawrence persevered until, finally, one month later,
0:40:15 > 0:40:16they had a breakthrough.
0:40:17 > 0:40:20It was almost like someone had just turned on the light.
0:40:21 > 0:40:26It was like there was this calm serenity around the whole place.
0:40:27 > 0:40:30And Lawrence was like, "Well, this is it."
0:40:30 > 0:40:32And he got up and just walked towards the boma.
0:40:32 > 0:40:34There was just something different about her.
0:40:34 > 0:40:36And he was standing there
0:40:36 > 0:40:40and she put her trunk over the fence and touched him.
0:40:43 > 0:40:45It was the briefest moment of contact,
0:40:45 > 0:40:48but it proved to be a major turning point.
0:40:50 > 0:40:54It would take years of hard work to fully rehabilitate the herd.
0:40:54 > 0:40:57But, knowing the elephants had finally accepted them,
0:40:57 > 0:41:01David and Lawrence released the herd into the wider game reserve.
0:41:06 > 0:41:09A year and a half later, David was called upon again
0:41:09 > 0:41:11to help with another elephant in need.
0:41:13 > 0:41:15A young female named ET.
0:41:18 > 0:41:21She was just ten years old at the time
0:41:21 > 0:41:23and she'd lost her whole family.
0:41:27 > 0:41:30And she was so traumatised, she'd lost her voice.
0:41:31 > 0:41:34It was almost like we were watching the same movie again.
0:41:34 > 0:41:36Except, we had this individual.
0:41:44 > 0:41:47All David and Lawrence knew was that they had to help her.
0:41:48 > 0:41:52ET was moved to their reserve and placed in a safe enclosure,
0:41:52 > 0:41:55while they figured out how they could rehabilitate her.
0:42:00 > 0:42:03And while we were asking ourselves these questions on how to do it,
0:42:03 > 0:42:05well, the herd answered it for us.
0:42:06 > 0:42:09They turned their back to the boma, where ET was,
0:42:09 > 0:42:10and they started communicating.
0:42:12 > 0:42:14And you could really see she was starting to settle down.
0:42:14 > 0:42:17Immediately settle down.
0:42:17 > 0:42:19And Frankie came to the fore
0:42:19 > 0:42:24and immediately just took ET under her wing, so to speak.
0:42:26 > 0:42:30Is it the case that Frankie could relate to how ET was feeling
0:42:30 > 0:42:33and can we go as far as saying it took her back to how she felt?
0:42:33 > 0:42:36And, therefore, she wanted to protect this little one
0:42:36 > 0:42:38because she could understand what she was going through,
0:42:38 > 0:42:40because she'd gone through it herself?
0:42:40 > 0:42:44It was clear that they recognised this young female
0:42:44 > 0:42:48was crying out for help, was in desperate need of help,
0:42:48 > 0:42:52was in need of social bonding, was in need of emotional stability.
0:42:52 > 0:42:53And they gave it to her.
0:42:53 > 0:42:55What do you think would have happened
0:42:55 > 0:42:57if the herd hadn't approached ET
0:42:57 > 0:43:00and Frankie hadn't reached out to ET?
0:43:00 > 0:43:01She quite possibly could have died.
0:43:03 > 0:43:06The support and friendship Frankie gave her
0:43:06 > 0:43:07could well have saved ET's life.
0:43:10 > 0:43:12Having heard their remarkable story,
0:43:12 > 0:43:15I want to meet these closest of companions for myself.
0:43:19 > 0:43:23I'm told that ET has a six-month-old calf.
0:43:23 > 0:43:27It's a sign of just how well she's settled into the herd.
0:43:33 > 0:43:35Oh, my gosh... Look at this.
0:43:38 > 0:43:41They've come a long way from their troubled past,
0:43:41 > 0:43:42but they're still wild elephants.
0:43:44 > 0:43:47Any encounter will always be on their terms.
0:43:47 > 0:43:50- This is Frankie on the left? - On your left, yeah.- On the left.
0:43:50 > 0:43:51Hello, my darling.
0:43:51 > 0:43:52Oh, my gosh...
0:43:53 > 0:43:54Hello, my darling.
0:43:55 > 0:43:58- And this is Frankie here? - Frankie and ET.
0:43:58 > 0:43:59ET!
0:43:59 > 0:44:01Frankie and ET. You see the baby there? There's ET's baby.
0:44:01 > 0:44:03Hello, my darlings!
0:44:03 > 0:44:08Getting so close to ET and Frankie is very special.
0:44:08 > 0:44:10And the herd's connection with David is remarkable.
0:44:10 > 0:44:13Hello, my darling. Yes, my girl. Yes.
0:44:13 > 0:44:14Hello, Frankie.
0:44:15 > 0:44:19David doesn't take credit for saving ET's life.
0:44:19 > 0:44:20He gives that honour to Frankie.
0:44:24 > 0:44:26But the story doesn't end there...
0:44:30 > 0:44:34What's even more remarkable is the relationship that developed
0:44:34 > 0:44:38between the herd and the man who saved them in the first place,
0:44:38 > 0:44:39Lawrence Anthony.
0:44:41 > 0:44:43Lawrence's wife, Francoise,
0:44:43 > 0:44:46watched that relationship develop over the years.
0:44:47 > 0:44:50It was like erm...spectacular.
0:44:51 > 0:44:53You could see the love.
0:44:53 > 0:44:55You could see the trust.
0:44:55 > 0:44:56You could see the feelings.
0:44:57 > 0:45:00Lawrence had never worked with elephants
0:45:00 > 0:45:02before he rescued Frankie's family.
0:45:04 > 0:45:08He was very spontaneous, he had that child enthusiasm,
0:45:08 > 0:45:10you see, of anything is possible.
0:45:10 > 0:45:13Lawrence, like, every day used to go and spend two, three hours
0:45:13 > 0:45:15with the herd of elephants
0:45:15 > 0:45:19and this is what created that most amazing, amazing relationship.
0:45:20 > 0:45:24Whenever Lawrence left the reserve for more than a day or two,
0:45:24 > 0:45:27the herd would often appear outside his house when he returned.
0:45:30 > 0:45:34Even with 4,000 kilometres of natural reserve to roam in,
0:45:34 > 0:45:37it seems they chose to seek Lawrence out.
0:45:40 > 0:45:44But on the 2nd of March 2012, Lawrence died unexpectedly.
0:45:48 > 0:45:52Frankie's family hadn't been seen at Lawrence's house for some time.
0:45:54 > 0:45:57But, on that day, they marched 12 hours to get there.
0:46:02 > 0:46:03When they arrived,
0:46:03 > 0:46:05the herd stood in total silence.
0:46:07 > 0:46:09They stayed by the house for two days.
0:46:13 > 0:46:16Exactly one year later, to the day,
0:46:16 > 0:46:18the herd marched again.
0:46:19 > 0:46:22Since then, they've come to Lawrence's house
0:46:22 > 0:46:25on the anniversary of his death every year.
0:46:29 > 0:46:32It's something which is more than emotional.
0:46:32 > 0:46:35It's beyond our understanding.
0:46:35 > 0:46:38Their intelligence, their sensitivity,
0:46:38 > 0:46:41their sensibility, their emotions.
0:46:43 > 0:46:45Do we know everything?
0:46:45 > 0:46:47I think we've got so much to learn from them.
0:46:49 > 0:46:52It's not something that science can explain
0:46:52 > 0:46:54and, of course, there's every possibility
0:46:54 > 0:46:57that these could be extraordinary coincidences.
0:46:57 > 0:47:02But could it be that the elephants were responding to Lawrence's death?
0:47:09 > 0:47:14It makes me think about grief and its place in the animal kingdom.
0:47:19 > 0:47:22If animals are capable of grieving
0:47:22 > 0:47:25can this help us to answer the ultimate question?
0:47:25 > 0:47:26Do they love?
0:47:27 > 0:47:31To explore this, I've come to Dorset in the UK
0:47:31 > 0:47:34to find out about a devoted male, who lost his partner.
0:47:36 > 0:47:39Sam is a 22-year-old siamang gibbon
0:47:39 > 0:47:42and he was with his mate for more than a decade.
0:47:45 > 0:47:49Siamangs are renowned for forming lifelong relationships
0:47:49 > 0:47:51and for being extremely committed.
0:47:54 > 0:47:58Dr Alison Cronin is the director of Monkey World Ape Rescue Centre
0:47:58 > 0:48:01and she's known Sam almost all his life.
0:48:03 > 0:48:06If Alison has learned anything about caring for primates,
0:48:06 > 0:48:10it's that the nurturing of their relationships is absolutely vital.
0:48:11 > 0:48:13Obviously, we have very basic needs,
0:48:13 > 0:48:16in terms of food and water and that kind of thing.
0:48:16 > 0:48:18But, in terms of your lifestyle and emotions,
0:48:18 > 0:48:21the very most important thing to a human being
0:48:21 > 0:48:23or a siamang gibbon or a chimpanzee
0:48:23 > 0:48:26is companionship of their own kind.
0:48:26 > 0:48:3018 years ago, Sam was paired with the gibbon of his dreams,
0:48:30 > 0:48:33an attractive female named Sage.
0:48:33 > 0:48:36THE GIBBONS SING
0:48:37 > 0:48:38They immediate hit it off
0:48:38 > 0:48:40and, like all siamang gibbons,
0:48:40 > 0:48:43they proudly announced their relationship to world
0:48:43 > 0:48:45every day with a song.
0:48:49 > 0:48:53So how important is song to the siamangs?
0:48:53 > 0:48:56The duet is critical for a couple of reasons.
0:48:56 > 0:49:00For their social pair bond, you sing with people,
0:49:00 > 0:49:02your partner that you love,
0:49:02 > 0:49:04and your song becomes tighter and better.
0:49:04 > 0:49:08And it also announces your territory to other neighbouring groups.
0:49:08 > 0:49:10So, it's a way of you two sticking together
0:49:10 > 0:49:13and telling everybody else, "Go away, this is our patch."
0:49:16 > 0:49:19Over the years, the pair grew closer.
0:49:19 > 0:49:22So much so, they rarely spent a moment apart.
0:49:25 > 0:49:28It's seemed Sage and Sam were the perfect match.
0:49:35 > 0:49:38Five years into their relationship, they started a family.
0:49:42 > 0:49:45The team at Monkey World took great pleasure
0:49:45 > 0:49:48in naming Sam and Sage's son Onion.
0:49:52 > 0:49:55Sam and Sage weren't just a great partnership,
0:49:55 > 0:49:57they proved to be great parents, too.
0:49:59 > 0:50:00Just like any young gibbon,
0:50:00 > 0:50:04Onion learned to sing from both his mother and father.
0:50:04 > 0:50:06GIBBONS SING
0:50:06 > 0:50:08You could start hearing a little third voice.
0:50:08 > 0:50:13And often, that third voice is out of tune, out of key, out of place.
0:50:13 > 0:50:14And, "Yaaaaaah!" You know?
0:50:14 > 0:50:17Different noises here and there and it's quite funny to watch.
0:50:17 > 0:50:19SINGING
0:50:25 > 0:50:28The trio lived happily together for eight years.
0:50:30 > 0:50:31Until tragedy struck.
0:50:33 > 0:50:36Unexpectedly, Sage died.
0:50:36 > 0:50:39She actually got a peach pit embedded in her gut
0:50:39 > 0:50:42and it took her out, sadly.
0:50:42 > 0:50:44So, it was sad for all of us here at the park
0:50:44 > 0:50:47but, in particular, for Sam, her devoted partner,
0:50:47 > 0:50:50who had been with her for 13 years singing that song
0:50:50 > 0:50:54and just every day reaffirming that they were a pair.
0:50:58 > 0:51:00Sam was so profoundly affected
0:51:00 > 0:51:02by the sudden loss of his long-term partner,
0:51:02 > 0:51:05he stopped singing his song.
0:51:07 > 0:51:10For a siamang, it's almost a double tragedy.
0:51:10 > 0:51:13You lose your mate, you lose your song.
0:51:13 > 0:51:15Potentially, that means you lose your territory.
0:51:17 > 0:51:18In the wild,
0:51:18 > 0:51:22Sam might not have been able to defend himself from other gibbons.
0:51:23 > 0:51:27In a sanctuary, he was spared the loss of his home.
0:51:27 > 0:51:30But losing his partner had a huge impact.
0:51:37 > 0:51:39Sam became completely withdrawn.
0:51:39 > 0:51:41He struggled to eat
0:51:41 > 0:51:43and would sit alone in complete silence.
0:51:53 > 0:51:58For his keeper, Cat Talbot, it was heart-breaking to see him suffer.
0:51:58 > 0:52:01But, unfortunately, things were only going to get worse for Sam.
0:52:04 > 0:52:07His son Onion became critically ill.
0:52:08 > 0:52:11Tragedy was to strike us again,
0:52:11 > 0:52:12because Onion actually had
0:52:12 > 0:52:15a massive cancerous inoperable tumour in his bowel
0:52:15 > 0:52:19and we actually had to euthanize him rather than bring him back.
0:52:19 > 0:52:22So, almost two years later, he lost Onion.
0:52:23 > 0:52:26When he lost Onion, he had no-one and he was on his own.
0:52:26 > 0:52:30Sam, basically, would just sit in a corner with his head down
0:52:30 > 0:52:32and just looked really, really miserable.
0:52:32 > 0:52:36He was really looking for physical contact with us
0:52:36 > 0:52:39and the easiest way for that was just to hold our hands.
0:52:39 > 0:52:42And where it became really difficult emotionally for us
0:52:42 > 0:52:44was when we tried to pull our hands away,
0:52:44 > 0:52:47to go away and look after all the other gibbons
0:52:47 > 0:52:48or do some work or whatever.
0:52:48 > 0:52:51Sam would actually tighten his grip and kind of hold on to you
0:52:51 > 0:52:54and kind of make it clear that he really didn't want you to go.
0:52:56 > 0:52:59Once again, it would take weeks for Sam to recover.
0:53:02 > 0:53:06His behaviour certainly resembled what we would describe as grief.
0:53:08 > 0:53:09But is that possible?
0:53:10 > 0:53:14There's no doubt about it in my mind that non-human primates
0:53:14 > 0:53:16and siamangs, specifically,
0:53:16 > 0:53:20can experience grief and sadness.
0:53:20 > 0:53:22Definitely, Sam went downhill.
0:53:22 > 0:53:25He went off of his food, he wasn't behaving properly,
0:53:25 > 0:53:27he was depressed.
0:53:27 > 0:53:30And that kind of grief isn't good for him.
0:53:31 > 0:53:34So, what does Sam's behaviour tell us?
0:53:36 > 0:53:38If animals do grieve,
0:53:38 > 0:53:41does it help us to answer the ultimate question?
0:53:42 > 0:53:43Do they love?
0:53:46 > 0:53:50Does that add to the evidence they might feel love in the first place,
0:53:50 > 0:53:52to feel that way when they lose their partner?
0:53:52 > 0:53:54Yeah, I'd like to think that,
0:53:54 > 0:54:00not only do they have an incredible pair bond, for a survival reason,
0:54:00 > 0:54:02but that it is a true reflection of love.
0:54:04 > 0:54:06Sam went through an extremely difficult time.
0:54:08 > 0:54:11But a year and a half after he lost Sage,
0:54:11 > 0:54:13he was introduced to a female called Sasak.
0:54:15 > 0:54:19And to everyone's relief, the pairing was a complete success.
0:54:20 > 0:54:22SINGING
0:54:25 > 0:54:28At the ripe old age of 19,
0:54:28 > 0:54:30Sam had a reason to sing again.
0:54:30 > 0:54:33SINGING
0:54:36 > 0:54:39Seeing them, their behaviours and the way that they communicate,
0:54:39 > 0:54:41the way that they touch, the way that they respond,
0:54:41 > 0:54:46I would definitely say that they feel the same emotions that we do.
0:54:46 > 0:54:48And I don't see why we can't allow them that.
0:54:49 > 0:54:53You sing the song to announce to everybody this is how tight we are.
0:54:53 > 0:54:57That, if they come into that territory, you're going to go to war
0:54:57 > 0:54:58and that's because you're together.
0:55:00 > 0:55:01That's got to be love.
0:55:01 > 0:55:02They're in it together
0:55:02 > 0:55:04and they're prepared to put their necks on the line
0:55:04 > 0:55:06and not many people would do that.
0:55:17 > 0:55:21I have been amazed at the sheer variety
0:55:21 > 0:55:23of relationships animals can build.
0:55:25 > 0:55:27And just how many benefits they gain from them,
0:55:27 > 0:55:30far beyond the need to have offspring.
0:55:31 > 0:55:33Now, we're only just beginning to understand
0:55:33 > 0:55:36the complex emotions animals are capable of,
0:55:36 > 0:55:38but is it possible that they love?
0:55:40 > 0:55:43To want to be with another individual, to protect...
0:55:44 > 0:55:47..I don't see why we wouldn't call that love.
0:55:48 > 0:55:50Not only are they capable of love,
0:55:50 > 0:55:53but the way they demonstrate that love is very similar,
0:55:53 > 0:55:56in terms of compassion and genuine caring and comfort.
0:55:56 > 0:55:58That is love.
0:55:58 > 0:56:01These animals, definitely, without a doubt,
0:56:01 > 0:56:02show genuine emotions to each other.
0:56:02 > 0:56:04So, whatever you want to call it,
0:56:04 > 0:56:06love or emotional intelligence, absolutely.
0:56:07 > 0:56:11Science is discovering that the hormones, the chemicals,
0:56:11 > 0:56:15the emotions that drive animals to seek each other out and stay together
0:56:15 > 0:56:18are similar in many species, including us,
0:56:18 > 0:56:23and may well be at the root of what humans call love.
0:56:23 > 0:56:25So, if we have those drives in common,
0:56:25 > 0:56:27then, can't we say animals love?
0:56:28 > 0:56:30Just straight in front of us...
0:56:30 > 0:56:31Next time...
0:56:33 > 0:56:37..having discovered that some animals seem to share our deepest emotions...
0:56:39 > 0:56:42..I set out to explore the weird and wonderful ways
0:56:42 > 0:56:44they get together in the first place.
0:56:46 > 0:56:48I'll meet the trail-blazing monkeys
0:56:48 > 0:56:51who've developed the most outrageous technique to attract a mate.
0:56:53 > 0:56:55He's not paying me any attention. What if I throw it?
0:56:59 > 0:57:02I'll come face-to-face with a ferocious flirt
0:57:02 > 0:57:05to hear one of the oldest love songs on the planet.
0:57:05 > 0:57:06DEEP, SONOROUS SOUND
0:57:06 > 0:57:11The most extraordinary set of events unfolding...
0:57:13 > 0:57:15And I'll reveal 21st century dating,
0:57:15 > 0:57:17orang-utan style.
0:57:19 > 0:57:20He was playing hard-to-get.
0:57:20 > 0:57:23Yes, he didn't seem to be very interested.