The Social Cat The Truth about Lions


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The Social Cat

Lions are strangely social, the only wild cats to live in family groups. Jonathan Scott investigates why, with the help of the Marsh Pride of the Masai Mara.


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Skilful hunters.

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Violent and terrifying man-eaters.

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Devoted parents.

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'I'm Jonathan Scott and I've been captivated by lions all my life.'

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And for the last 30 years,

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'I've been watching, sketching, photographing and filming'

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one amazing lion pride, by day, and under the cover of darkness.

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And I've seen first-hand what makes lions unique.

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Whilst other big cats live solitary lives, lion's don't.

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They live in large family prides.

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The lion pride is the exception amongst the cat family.

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No other species lives this kind of social existence.

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Now, new research is revealing the reason for the lion's unique lifestyle.

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'Assumptions and misconceptions are being overturned.'

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We want to know, why are lions social?

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I'm going to look again at this unique animal.

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I'm searching for The Truth About Lions.

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I can hardly believe it's almost 40 years ago

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since I arrived in Africa with a degree in Zoology.

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I was passionate about wildlife and, in particular, I was fascinated by big cats.

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I wanted to explore every detail of their lives. I wanted to write about them, photograph them, draw them.

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In fact, I wanted to get right under their skin, to know them as individuals.

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And what better place to do that than right here,

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in the Maasai Mara in Kenya.

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The Maasai Mara is the northern tip of the vast Serengeti

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that stretches for 120 miles to the south, in Tanzania.

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This is classic African savannah, large areas of open grassland,

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scattered trees and small rivers criss-crossing the terrain.

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And running through the whole reserve on its journey to Lake Victoria is the mighty Mara river.

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This place is home to perhaps the most famous lions in the world...

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ROARING

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..The Marsh Pride.

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Together with colleagues from the BBC, I've filmed them extensively for shows such as Big Cat Diary.

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At times, under 24-hour surveillance...

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..revealing their lives in extraordinary detail.

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This particular pride of lions, the Marsh Pride, they're like family to me and I've been recording

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every detail of their life, going back to 1977. This notebook, 1981.

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And that's always been the fascination for me, the detail.

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But what drove lions to form prides in the first place?

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Why are they so different from all of the other cats?

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It's the fundamental question about lions that I'm still unable to answer satisfactorily.

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But over the border in Tanzania's Serengeti National Park is a project which could help me.

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The Serengeti is vast, equivalent in area to the whole of Wales,

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and, like the Mara, it's a stronghold for lions.

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It's home to the Serengeti Lion Project,

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the longest-running lion research project ever.

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This is the reproductive rates. Over 40 years of data, across our study area.

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They're about four or five.

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'It began in 1966 and, since 1978, it's been headed by Craig Packer.

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'the foremost lion scientist in the world.'

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Some places have very low reproduction, others are really high, especially up here.

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'He's been studying these cats for as long as I've been in Africa.

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'yet we've only met once before, 25 years ago.

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'So this meeting is long overdue.'

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My focus has very much been a single pride, the Marsh Pride, which I know

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intimately and I love that sense of knowing the group, but we're talking

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30 lions, maximum. Yes, I see the other lions at times that surround them, but for you, very different.

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Here we're trying to look at a population, so we look at between 13 and 28 prides

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at any one time, so over all the decades here, we've got data now on 5,000 lions.

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-5,000.

-Totally different approach.

-Yes.

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The first thing was, we had a long history in the study and so we inherited those records,

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so when I got here we already knew who the grandmothers were of some of the adult females,

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but we didn't know much about paternity until later, when we did DNA fingerprinting.

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We were one of the first animal projects to use the genetic tools

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to understand the kinship within a pride.

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Another thing that I've loved in the Mara is that I've been able to watch lions, leopards, cheetahs

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and I could really, sort of, see how different lions are to those other animals.

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And the key question has always been, I think for you, too,

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is, why are lions social? Can we answer that question now?

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Finally I think we have a good answer on this. It took us a long time. There were different ideas

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that had been floating around. We went through them all, one by one. But each took several years

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to answer, much longer than we thought,

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and it took us 30 years before we felt we'd nailed the answer.

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For over 30 years, Craig and his team of researchers

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have collected vast amounts of data, from 28 study prides,

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testing the many theories that have been proposed to explain the lion's sociality.

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What's the driving force that binds individual lions together in prides?

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A social structure amongst the most complex of any group-living animal.

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There are animals like meerkats and baboons that form troops or packs and they're always together,

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but a lion pride is much more complicated than that.

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The lion pride is more like a human family, where one individual may go off and do something

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on their own for a while, and then they come back.

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And so you begin to realise it's a great intricacy, there's

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a great complexity to this social system, that's far more elaborate than we see in most other animals.

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It's that complexity that's kept me fascinated by the Marsh Pride all these years.

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What I want to do now is take all the information that

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Craig and his team have collected and take another look at my pride. And see how it matches up.

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Ironically, to understand the complexity of a pride, you need to know all its members as individuals.

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Naming them does help.

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But telling lions apart in the field isn't easy.

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Thankfully, in the early 1970's, a method was discovered.

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Every lion, as it turns out, has its own unique pattern of whisker spots,

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which act just like a human fingerprint.

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By recording the behaviour of the named individuals in my pride,

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the reason behind pride living can be revealed and investigated.

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Let's just take a look at what the Marsh Pride are up to right now,

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I'm just going to draw a map here of their territory in the sand.

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It's about 20 miles, that's about 50 square kilometres, so quite big.

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River's over here, the marsh is there

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and right here, we've got two older generation females,

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that's White-Eye, Bibi and four of White-Eye's cubs.

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At 12 years old White-Eye, so called as she is blind in one eye, is the oldest female in the pride.

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I've seen female lions in the Marsh Pride reach 15,

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but despite her age, right now, she's the newest mum.

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Her four young cubs rely on her for everything and will stick with her for at least two years.

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Alongside White-Eye in this part of the territory

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is one of her pride mates, another 12-year-old lioness, called Bibi.

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Over here, towards the west, I've got another older generation female,

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that's Lispy, with nine sub-adults - five males, four females.

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Lispy is Bibi's sister from a litter born in the pride in 1998.

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The sub-adults with her are the sort of teenagers of the pride,

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almost, but not quite, ready to go it alone. They're free to roam throughout the territory,

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They need to, in order to find enough food to satisfy so many hungry mouths.

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And right at the other side of the territory,

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we've got Clawed and Romeo, the big pride males.

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At 12 and ten years old, they're clearly powerful lions.

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Unlike the females, who will live their whole life in the same pride, the adult males have to fend off

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challenges from younger rivals and, on average, their tenure as a pair is rarely longer than two years.

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Clawed and Romeo have now been pride males for over three years.

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They're living on borrowed time.

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And that's not all.

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They're spending much of their time, maybe too much of it,

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with a breakaway trio from the Marsh Pride, that we call The three Graces.

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These females have also had cubs, but are keeping well away from the main pride, for the moment at least.

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Now you might think it's unusual to have members of the same pride

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scattered all over the territory like this,

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but I've seen it many times before.

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The fact that the individuals of the Marsh Pride aren't all together right now is brilliant timing.

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Watching how the three distinct factions operate and seeing when and why they come back together

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as a whole pride will help me make sense of Craig and his team's huge amount of work

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and unravel the fundamental reason behind pride living.

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Along the way, discovering a wealth of surprises about these magnificent creatures.

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March is normally dry in the Maasai Mara,

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a traditionally lean time for my lions.

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The famous wildebeest migration is 120 miles south in Tanzania and my lions are hungry.

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The need for food unites all three factions of the Marsh Pride.

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But the starkest difference between the pride factions at the moment

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is between those with young cubs and those without.

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White-Eye has four young cubs to feed.

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And they're thin.

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With such a sparsity of prey at this time of year, White-Eye and her only adult lioness companion, Bibi,

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are forced to hunt even during the heat of the day.

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And they must travel large distances away from the cubs, leaving them vulnerable.

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But the nine young lions in Lispy's gang are far more self-reliant and can hunt as a team.

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This is the group that is perhaps most like many people's idea of a lion pride.

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Does their strength in numbers mean they'll fair better than White-Eye and Bibi?

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Could co-operative hunting - lions helping each other to gain a meal -

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be the reason why they became social in the first place?

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Is that why they form prides?

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Co-operative hunting has long been considered by many as THE reason why lions live in prides.

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But how does it stack up, when looked at closely?

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The gang spot an opportunity too good to miss,

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a pair of mating warthogs, whose attention lies elsewhere.

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Older, more experienced, Lispy leads the front -

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the perfect ambush predator.

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But the sub-adults do appear to be co-operating and working with her.

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Eyes are locked on the target, as they fan out...

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..closing the net on their prey.

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Surely with this many lions, the warthogs don't stand a chance?

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In fact, the warthogs give them the slip.

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It seems here, at least, that hunting as a group didn't help,

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so just how strong is the evidence?

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This was Craig and the project's first line of investigation.

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If co-operation was a strong advantage from hunting, we would think of two possible ways

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that it helps. First is, it means the group will be more successful than a solitary,

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so they might succeed 40-50% of the time, instead of 10% of the time.

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And in fact, that's not seen, there's not a huge improvement in group performance

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by having more animals hunting together.

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And the second way that co-operation can be important is that a larger group can pull down a prey item

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that a solitary cannot possibly capture on her own and that we do see.

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So, group hunting is needed, in order to take large prey.

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And it is usually seen as the main advantage lion prides have over solitary cats.

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The buffalo is the lion's most formidable opponent.

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Over half a tonne of solid muscle.

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Where a single lion would struggle, together there is strength in numbers.

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Lions do co-operate when they're trying to catch buffalo and in

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reports of lions catching hippo, those have to be done by a group.

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But those are not essential in terms of keeping the pride well nourished through a year.

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Co-operative hunting, it turns out, is essential to take down large prey but the advantage it brings to lions

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isn't enough to drive the evolution of pride life alone. And it could be looked at as a disadvantage,

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forcing lions to work together to bring down large animals, like buffalo.

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If you are in a group,

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you have the problem of dividing the prey into ever smaller shares,

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but you can overcome that cost by actually going for the larger prey.

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So we could almost look at a preference for larger prey, as a way of compensation

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against the cost of having to share out one meal amongst many mouths.

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When, as I've seen, individual lions catch smaller prey, they can keep all the food for themselves.

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So why are Lispy and the gang hunting small warthog as a group?

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This, it turns out, is an illusion.

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Small prey predominates in the territory right now.

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Only one lion actually takes down the warthog, yet it appears as if

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they're co-operating, as the rest of the group have to be close to stand a chance of getting any food.

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Scrapping over the spoils is normal in lion prides and those closest

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to the action get significantly more food than the others.

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Once the prey is down, any pretence of co-operation is gone.

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They're so incredibly selfish and aggressive to each other.

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They're snarling at each other, they're pulling food out of each other's mouth.

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How could you really imagine that this animal's so nobly co-operative, given the incredibly

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grabby table manners they have, once they've actually got dinner in front of them?

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It's like they're eating together, despite the fact that it's such an annoying thing to do.

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They're together for some other reason.

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So, co-operative hunting alone can't explain why lions form groups.

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Co-operative hunting is something that lions can do because they live in groups,

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but it isn't the reason why they evolved this social way of life in the first place.

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Craig and his team needed to keep looking for answers.

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So what about the cubs?

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After all, the success of any lion pride is judged by the numbers of cubs it can raise over time.

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Watching how the cubs in my pride are nurtured and protected is revealing.

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They grow fast and begin eating meat at just six to eight weeks old.

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The young cubs feeding on a fresh kill belong to the three Graces' faction of the pride.

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In these lean times, cubs would normally have to scrap at the dinner table with the adults,

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fighting their corner for food.

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But not here.

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The mothers are being kept from the kill by adult pride male, Romeo.

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Himself, also showing surprising restraint.

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This is behaviour I've witnessed before and is a graphic illustration of how vital cubs are,

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not only to their mothers, but also to their fathers, the pride males.

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As the likely father to these cubs, Romeo's behaviour actively ensures

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his offspring, the future of his genes, gets the best start in life.

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Males of all other cat species play no role in the raising of their cubs

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but here, once again, lions are different.

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If cubs growing up in a pride had better nutrition

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and, as a result, better survival prospects, then this advantage could be the explanation for pride living.

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It's been one of the most strongly favoured theories over the years.

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Until now.

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When I first started studying lions, people used to think of

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mother lionesses as suckling their cubs communally,

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as nurturing them as a group. Could that be the reason why lions became social in the first place?

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For the first three months of life, White-Eye's four young cubs are dependent on milk.

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As her companion Bibi isn't lactating, the cubs are entirely dependent on their mum.

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There are no other females in this section of the territory.

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The more usual situation in a pride, is one of multiple mothers

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and multiple litters of cubs, forming a creche.

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It's a situation I've seen

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many times in the Marsh Pride.

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When White-Eye herself was a cub, she was nurtured in a creche with multiple mothers.

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And it does appear that cubs are being suckled by all the mothers indiscriminately.

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But does communal suckling give cubs in a creche an advantage over those

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raised by single mothers, like White-Eye?

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It's really fascinating that lions are one of the few species

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where cubs may nurse from more than one female.

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But when we looked at it in much more detail,

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we found there's a lot of conflict of interest going on.

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In fact, each mother would prefer to nurse only her own cubs.

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The problem for the mothers is,

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they've been out all night, looking for food.

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They've come back and they've got to sleep and so they've got to

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divide their time between allowing their cubs to catch up with them and then also to get a good nap.

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So it turns out the cubs are very crafty and they'd wait till the mothers were asleep

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and then they'd go sneaking in to another female that wasn't their own.

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So there wasn't that much real co-operation going on,

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but that the cubs are more like parasites, taking advantage of the inattentiveness of the mothers.

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And crucially, watching White-Eye's four cubs here

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shows that they are getting enough milk just from their own mother.

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Boisterous enough now to get on Bibi's nerves.

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Closer investigation by Craig and his team showed that whilst cubs in a creche can suckle

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from multiple mothers, they don't get any nutritional advantage.

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And the data clearly shows their survival chances are not increased.

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If communal suckling doesn't help us to answer why lions are the only

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living social cat, what else is there that could have driven lions to form prides?

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Perhaps the answer is defence.

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THUNDER

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They may be near the top of the food chain, but lions of the Marsh Pride

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still live in danger, from predators close to home.

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Two young, strong male outsiders are sniffing around the edge of the Marsh Pride,

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in search of territory and females with whom they can breed.

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Males, who given the chance will try to oust the current

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aging pride males, Clawed and Romeo.

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They spot Lispy and the eight young lions.

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It may be two against nine, but Lispy and the gang recognise the threat posed by them.

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The pair target their attack on the young males in the group,

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as chasing them off could give them access to the females.

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This bold incursion into Marsh Pride territory is perhaps

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their first show of serious intent - and more may follow.

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To win the Marsh Pride territory, the outsiders will ultimately

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need to displace the current pride males, Romeo and Clawed,

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an encounter which could happen at any moment.

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But Romeo and Clawed may be spending too much time with the three Graces,

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leaving the rest of the pride vulnerable.

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And for vulnerable, read, "cubs".

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If we think of cub rearing, it's not just a matter of delivering food to their young.

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Mothers also have to protect their young against various different enemies.

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We often think of an enemy of a lion as maybe being a leopard that might eat the cubs,

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but, in fact there's a much more common and more pervasive enemy - and that's their own species,

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And it's the male, the male that's not the father of the cubs.

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New males from outside the pride encountering young lions like White-Eye's cubs will kill them.

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Violent behaviour, known as infanticide.

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Infanticide is very common in nature and it's really widespread in the cats.

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If the fathers happen to be out patrolling the edge of the territory and a guy sneaks in,

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then the females may encounter a nomadic male, who will quickly try to eliminate the cubs.

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I've seen the impact of infanticide affect the Marsh Pride.

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Most dramatically, for a lone mother, known as Tamu, and her four young cubs,

0:32:280:32:33

spotted by a nomadic male.

0:32:330:32:37

To the male lion, the mother is a resource.

0:32:490:32:52

He wants to be able to have her rear his offspring. He doesn't want to be a stepfather.

0:32:540:33:01

So when he first encounters a new pride, he'll quickly

0:33:020:33:06

try to eliminate those cubs that prevent the mothers from mating again for a year and a half.

0:33:060:33:11

For as long as Tamu had dependent cubs, at least 18 months, she would not be ready to mate.

0:33:130:33:19

Killing her offspring would bring her into season again

0:33:210:33:24

and give this male a chance to father his own cubs with her.

0:33:240:33:28

But lone females fight hard to protect their cubs.

0:33:300:33:34

Tamu fought off the nomadic male, but there was a heavy price to pay.

0:33:460:33:51

One cub was badly injured and later died.

0:34:000:34:03

This mother's struggle to chase away the incoming male

0:34:080:34:11

simply wasn't enough to protect all her cubs...

0:34:110:34:14

..which may be why most prides contain multiple mothers,

0:34:180:34:22

who, with their cubs, stick close together, forming a creche.

0:34:220:34:25

If Tamu and her cubs had been part of a creche, perhaps things would have been different.

0:34:310:34:36

A lone female has almost no chance to protect her cubs against a male.

0:34:420:34:46

The male's much bigger, but sisterhood is powerful.

0:34:460:34:50

Groups of females, working together, can stand up against the males,

0:35:040:35:09

chase them away and effectively protect their cubs.

0:35:090:35:12

So what you see with a creche, with a communal litter, is a defensive formation of females

0:35:160:35:20

always ready to defend their cubs against invading males.

0:35:200:35:24

At last, a reason for lionesses to group together - to protect their offspring.

0:35:310:35:36

Who could argue with that? But there is a niggle with this theory.

0:35:360:35:41

Lion's are not the only species with murderous stepfathers. You have other species that

0:35:440:35:50

are infanticidal, like leopards, tigers, house cats, but all those species are solitary.

0:35:500:35:56

So there's nothing unique about lions and facing that threat

0:35:560:35:59

of having males that might come in and kill the cubs.

0:35:590:36:02

The lions are already in a social formation, but then in this special

0:36:030:36:08

case where they have the young, they draw together even tighter,

0:36:080:36:11

so they're already living in a group, for some other reason.

0:36:110:36:14

Infanticide is not the root cause of their sociality.

0:36:140:36:18

So, on detailed investigation,

0:36:280:36:30

it turns out that many of the obvious theories citing co-operative hunting...

0:36:300:36:35

..communal suckling...

0:36:360:36:38

..or protection from infanticide

0:36:400:36:42

as the cause of lion prides don't provide the answer.

0:36:420:36:45

'And remember these are theories I've held myself for many years.'

0:36:510:36:56

With the main behavioural theories discounted, Craig and his team turned their attention

0:37:130:37:18

to the places where lion prides lived.

0:37:180:37:21

For my pride, the Marsh Pride, the extent of their territory

0:37:240:37:28

has remained constant over all my years of watching them.

0:37:280:37:32

Looking at how they use, defend and roam within their territory

0:37:360:37:41

could hold the secret to understanding pride living.

0:37:410:37:44

After their encounter with the nomadic males, Lispy and the gang

0:37:530:37:58

have scattered and relocated to the opposite side of the territory.

0:37:580:38:01

Away from the intruders, but into the area that the splinter group,

0:38:030:38:07

known as the three Graces consider theirs.

0:38:070:38:10

The three Graces, although once part of the main pride,

0:38:220:38:26

do not tolerate other lions in what they consider as their territory...

0:38:260:38:30

..even if they are part of the same extended family.

0:38:310:38:34

The three Graces give short shrift to two of the young lions

0:38:500:38:54

from Lispy's gang, who have become separated from the main group.

0:38:540:38:58

This is the real relationship between neighbouring prides.

0:39:510:39:54

Constant readiness to do battle, held in check by the threat of mutually-assured destruction.

0:39:540:40:02

Having shown who's boss, the three Graces move off.

0:40:050:40:10

The most violent encounters amongst lion prides are always over territory.

0:40:200:40:25

The space in which lions live is so important that they literally shout about it.

0:40:320:40:37

ROARING

0:40:370:40:42

The lion's roar is amazingly primal, a terrifying sound.

0:41:040:41:09

It's the declaration of territory ownership - "This is my place."

0:41:090:41:14

But what can it tell us about the evolution of prides?

0:41:170:41:20

To understand the roar in more detail, Craig and his team needed to start talking to the lions directly.

0:41:220:41:28

We were able to record roars and then broadcast them back to the lions.

0:41:310:41:35

And much to our surprise, they responded as if there was

0:41:370:41:41

a real invader, right there in their bedroom.

0:41:410:41:43

And the fact that lions often roar as a group gave the team a bit of a headache.

0:41:500:41:55

To investigate, they had to play back different numbers of lions

0:41:550:41:59

roaring to different numbered groups of real lions,

0:41:590:42:03

but it produced perhaps the most surprising results of all of Craig's research.

0:42:030:42:10

When we played back the roars, if we did one against one, there was no response,

0:42:100:42:15

but three against one, they would always respond.

0:42:150:42:18

And then we played the roars of three back to a group

0:42:200:42:23

and three against three was the same as one against one

0:42:230:42:26

and five against three was exactly the same as three against one.

0:42:260:42:29

So with three invaders, five real lions would always go forward. That meant they could count.

0:42:310:42:36

They could count how many invaders there were and how many they had in their own group,

0:42:360:42:40

to be able to fight against the strangers. They could calculate the odds.

0:42:400:42:43

As long as they outnumbered their opponents by two,

0:42:470:42:50

lions would move towards rivals that appeared to be in their territory.

0:42:500:42:55

That was the first experiment to show any animal, besides humans, could count

0:42:550:42:59

and so we were really astonished. We thought these dumb blondes were not up to this kind of thing,

0:42:590:43:04

but when it came to the fights against their neighbours, this was where they really were co-operative.

0:43:040:43:09

The most co-operative we've ever seen the lions is when it's life or death, it's us against them.

0:43:090:43:14

It's over territory that lions are the most co-operative, working together to declare

0:43:160:43:22

ownership and even willing to risk their lives in its defence.

0:43:220:43:26

ROAR AND COUNTER ROAR

0:43:290:43:33

Territory clearly held the key to understanding why lions evolved their unique way of life.

0:43:360:43:41

'The Marsh pride are a boundary pride.'

0:44:210:44:24

Whilst much of their territory is within the protection of the Mara reserve,

0:44:250:44:29

the absence of fences marking the boundary means part of their territory lies outside it.

0:44:290:44:35

It brings them into close contact with the local Maasai.

0:44:500:44:55

Lions have lived alongside pastoralists for hundreds, if not thousands, of years.

0:45:340:45:39

Tompoi and his family have grazed cattle here for as long as I can remember.

0:45:430:45:48

I first met him 30 years ago.

0:45:520:45:54

THEY CONVERSE IN MAASAI

0:45:560:46:00

Each day, he brings his cattle down to the edge of the reserve,

0:46:020:46:06

to the spring that feeds the marsh, for water, a route he's taken for many years.

0:46:060:46:11

And he regularly sees my lions in the area.

0:46:110:46:14

-You see the lions, the Marsh lions, every day?

-Every day.

0:46:210:46:24

The marsh is a key part of my lions' territory.

0:46:280:46:32

After all, that's why we call them the Marsh Pride.

0:46:320:46:35

Why is it so important?

0:46:360:46:38

Because this area provides shelter and ambush sites for them.

0:46:380:46:43

And, crucially, attracts the lions' prey, looking for water and grazing.

0:46:450:46:49

It's just as important an area for Tompoi,

0:46:580:47:02

giving his cattle year-round access to water.

0:47:020:47:05

-All of those cows are yours?

-Yeah.

-200?

-Yeah.

-Whoa.

0:47:100:47:14

'In many ways, the lion pride has similarities to human societies.'

0:47:210:47:24

A pride territory is like the ancestral family estate.

0:47:260:47:30

'In the same way that generation after generation of Tompoi's family have grown up and grazed cattle

0:47:350:47:42

in this area, generations of the Marsh Pride, too,

0:47:420:47:45

have been raised in this territory and continue to be so.

0:47:450:47:49

With so little prey in the area at this time of year,

0:47:560:47:59

the pride have been operating as three distinct factions.

0:47:590:48:03

But things are about to change.

0:48:050:48:07

Lispy approaches her two pride mates White-Eye and Bibi and is warmly greeted.

0:48:110:48:18

Lispy's approach is followed by the young lions of the group.

0:48:290:48:33

Whilst the mother's reaction to their daughters is warm, their sons receive a less welcoming reception.

0:48:350:48:42

The young males will be driven out of this territory, but females stay,

0:48:510:48:56

ultimately replacing their mothers, when they die, as the core of the pride.

0:48:560:49:01

Pride's are, at their heart, a matriarchal society.

0:49:090:49:14

The fact that I knew this generation's grandmothers and great-grandmothers as individuals

0:49:170:49:22

is proof how successful this pride has been in this territory.

0:49:220:49:26

But whilst I've studied the success of just this pride of lions,

0:49:370:49:41

the Serengeti Lion Project has been busy recording

0:49:410:49:44

the breeding success of a grand total of 28 study prides.

0:49:440:49:48

And only by doing that, have they been able to collect enough data to discover the critical role

0:49:510:49:57

territories played in shaping lion societies.

0:49:570:50:01

Plotting the long-term success of their study prides

0:50:030:50:07

on a map of the Serengeti revealed striking differences.

0:50:070:50:11

Some prides had vastly greater breeding success than others.

0:50:130:50:18

Shown here on a map as the deepest colour.

0:50:180:50:21

'And, most tellingly, those prides with the greatest success shared something in common.'

0:50:330:50:40

Craig, you've spent years examining the reasons as to why lions might be social.

0:50:450:50:50

You've ticked off the reasons that don't seem to fit the picture, so what is it?

0:50:500:50:54

Well, I wanted to bring you up here because I think the best way

0:50:540:50:59

to think about lion sociality is to look at the landscape.

0:50:590:51:02

If you look out across the plains, we see a river running through it

0:51:020:51:07

and along the river there are certain spots that tributaries run together. They're confluences.

0:51:070:51:13

Where you get water that persists well into the dry season,

0:51:150:51:18

moisture that attracts the prey, so that the lions can feed

0:51:180:51:23

throughout all of the year and shelter for the cubs.

0:51:230:51:26

These are the places that have the highest real estate value.

0:51:280:51:31

These are the places that a very successful female,

0:51:310:51:34

if she were a solitary, would not be able to hold onto by herself.

0:51:340:51:38

She would need to have her daughter stay with her.

0:51:380:51:41

Her daughter who would then work with her mum, as a unit,

0:51:410:51:45

to keep the strangers away and all the family jewels would be safe.

0:51:450:51:49

The lion pride is a joint defence system against invaders

0:51:490:51:53

who want to take away that high-valuable real estate.

0:51:530:51:56

The map revealed the common feature for all the enduringly successful prides.

0:52:020:52:09

Their territories were all centred around river confluences...

0:52:090:52:14

..areas Craig has dubbed "lion hot-spots".

0:52:170:52:19

There was a huge evolutionary advantage for lions to gang up, form prides, to hold and protect

0:52:250:52:33

those areas which offered the best long-term success.

0:52:330:52:36

Survival of the fittest - and the fittest here were those in prides.

0:52:420:52:47

The Project finally had their answer.

0:52:490:52:53

Pride life is a direct result of the landscape and the habitat in which lions evolved.

0:53:010:53:07

For over 30 years, I've thought that the reason for lions' social living

0:53:130:53:18

was somehow rooted in their behaviour.

0:53:180:53:20

But Craig and his team's work has elegantly shown that, in fact,

0:53:220:53:26

the root cause is not how, but where, they live.

0:53:260:53:30

The reason I've been able to watch so many generations

0:53:320:53:36

of the Marsh Pride is that their territory is a lion hot-spot.

0:53:360:53:39

This is what I came to Africa to see and I've been fortunate

0:53:500:53:54

to document the last 30 years of this amazing lion pride.

0:53:540:53:59

Whilst watching my lions has helped me make sense

0:54:020:54:05

of Craig and his team's work, their success and TV popularity masks a rather uncomfortable truth.

0:54:050:54:12

Something Craig brought home to me graphically, projecting 35,000-year-old cave paintings

0:54:180:54:24

from Europe onto a rock face in the Serengeti.

0:54:240:54:27

These are pictures from France.

0:54:310:54:34

This is amongst the oldest art in the world.

0:54:340:54:37

They were discovered about 15 years ago and it has more pictures of lions than almost any other species.

0:54:370:54:43

I mean, it's mind-boggling.

0:54:430:54:46

35,000 years ago, to capture the sense of the lion.

0:54:460:54:52

I mean, the quality of the observation is remarkable.

0:54:520:54:56

This shows something that you and I have been talking about already - the way you identify the lions.

0:55:010:55:06

-The whisker spots.

-They've drawn the whisker spots

0:55:060:55:09

and they didn't have Land Rovers, they didn't have binoculars.

0:55:090:55:12

So unless we had The Flintstones, I mean, this is all being done

0:55:120:55:15

without any assistance, from a safe distance presumably,

0:55:150:55:20

because look, the lions are relaxed and the artist was able to get all these details.

0:55:200:55:24

They were not scared of the lions while they were drawing.

0:55:240:55:27

And the next slide, we can see the way they're...

0:55:270:55:30

'Here were paintings from Southern France of lion prides in action, in staggering detail,

0:55:300:55:35

'much as I would draw them today, even down to the whisker spots.'

0:55:350:55:39

The Chauvet Cave, where the paintings are found,

0:55:480:55:51

is in the limestone cliffs that have been carved out by the Ardeche River.

0:55:510:55:55

And along with other paintings and artefacts, found as far apart as Alaska and Asia,

0:55:590:56:05

they reveal, graphically, how lions were once a truly global species.

0:56:050:56:09

In fact, after humans, the lion was once the most widespread land mammal on earth.

0:56:170:56:24

Today, the lion is restricted solely to Africa and a tiny population of perhaps just 350 lions in India.

0:56:320:56:39

And most of these populations are under threat.

0:56:400:56:43

There's real cause for concern.

0:56:450:56:48

The latest studies in the Mara show a decline of 30% in the lion population during the last 20 years.

0:56:500:56:57

And in Africa, as a whole, the population has dropped to perhaps just 25,000 lions.

0:56:570:57:03

Everywhere, virtually, the trend is downwards.

0:57:030:57:06

Understanding the way in which the habitat has shaped lion societies and how change to it can affect

0:57:070:57:13

these complex and fascinating creatures, is essential to helping to ensure their future success,

0:57:130:57:19

a future which right now is anything but certain.

0:57:190:57:23

Next time on The Truth About Lions....

0:57:260:57:29

The world of the Marsh Pride changes dramatically with the arrival

0:57:300:57:34

of the annual wildebeest migration.

0:57:340:57:36

There are some new cubs,

0:57:360:57:39

but the old guard are beginning to show their age.

0:57:390:57:42

And I discover how the lion's unique social nature could be part of the reason for their worrying decline.

0:57:450:57:51

If we look at all the remaining lion populations,

0:57:510:57:54

there's a number of tiny populations scattered around Africa,

0:57:540:57:57

but they need to be big enough, in order to be viable for the next century or the next millennium.

0:57:570:58:03

And we believe there's only six of those left in Africa.

0:58:030:58:06

Subtitles by Red Bee Media Ltd

0:58:270:58:30

E-mail subtitling@bbc.co.uk

0:58:300:58:33

Lions are strangely social, the only wild cats to live in family groups. Lion expert and BBC Big Cat Diary presenter Jonathan Scott investigates the reason why with the help of the most famous lion pride in the world - the Marsh Pride of the Masai Mara in east Africa.

Jonathan's intimate knowledge of this massive pride and their various subgroups helps him explore the possible reasons for the lion's social lifestyle. While there are some apparent benefits to living in prides, from co-operative hunting to raising cubs, none appear to be a reason enough to evolve social living. Now, after 30 years of intensive study, the Serengeti Lion Project, lead by Professor Craig Packer, may have finally found the answer and it could have direct consequences for the survival of the lion as a species.