NOVA

DAVID ATTENBOROUGH: Here in Southern England, the remains of ice age mammoths have just been discovered.

The bones reveal a species of mammoth that lived hundreds of thousands of years ago.

Must've been rather enchanting.

And carefully crafted stone tools show that early humans were here, too.

Really beautiful, actually.

A team of archaeologists is carrying out a forensic investigation of the site.

SALLY HOLLINGWORTH: It's like a time travel through the gravel.

(laughs) ATTENBOROUGH: Why were the mammoths here, and how did they die?

It's like a really big whodunit, isn't it?

ATTENBOROUGH: Could ancient humans have hunted them?

This is very typical of early Neanderthals.

ANNEMIEKE MILKS: This shows their technology was capable of distance hunting.

BEN GARROD: Oh!

MILKS: Brilliant.

ATTENBOROUGH: What can this remarkable site reveal about life and death in ice age Britain?

"Great Mammoth Mystery," right now, on "NOVA."

ATTENBOROUGH: You might expect to travel to remote parts of Siberia or South Dakota to uncover bones of ice age beasts.

But 90 miles west of my home in London, two of Britain's most prolific amateur fossil hunters have made the discovery of a lifetime.

(doorbell rings) I've come to meet Sally and Neville Hollingworth.

Hello!

(laughs) ATTENBOROUGH: Nice to meet you.

Lovely to meet you!

NEVILLE HOLLINGWORTH: Absolute pleasure to meet you.

SALLY HOLLINGWORTH: Come on in!

This is our humble home.

Gosh!

ATTENBOROUGH (voiceover): Sally and Neville both have office jobs, but they spend their weekends hunting for fossils.

Like me, they have a passion for doing so.

But theirs went rather farther.

SALLY HOLLINGWORTH: When we went on fossil hunts and Nev would invite me, and he passed me half a vertebrae.

It's Jurassic, it's marine reptile.

Yeah.

A couple of weeks later, he texts me to say, "I think I might've found the other half of that vertebrae.

"Do you fancy meeting for a drink and we'll see if they join together?"

(laughs) It's a good line, isn't it?

This is true!

(laughs) Well, of course.

And so we met, for a drink.

And ...they joined together!

NEVILLE HOLLINGWORTH: They joined together.

I thought, "Well, there we go, it's a match made in heaven... SALLY: And we clicked.

...then, isn't there?"

Not a dry eye in the house!

(laughs) NEVILLE HOLLINGWORTH: No, no, not at all, no!

SALLY HOLLINGWORTH: We've got some in the kitchen.

More fossils?

SALLY HOLLINGWORTH: Finds.

More finds.

I thought for a moment it was going to be sandwiches!

ATTENBOROUGH (voiceover): These are the finds I've come to see-- mammoth bones.

Wow, gosh.

And this is our kitchen dino.

(laughing) Yes.

Well, and I know it's a leg bone, isn't it?

Yes.

Yes.

Where was it?

NEVILLE HOLLINGWORTH: It was actually literally just sticking out of some gravel on the floor of a working quarry.

Which end?

This end.

So that bit...

So that was the... ...was all you could see?

That's all you could see.

We thought there might be a bit more of it.

So we started to excavate, and as we started digging, we found that it was actually a complete humerus of a mammoth.

This pelvis bone has actually gone through the processing plant and it dropped out in the, in the reject pile of the quarry.

ATTENBOROUGH (voiceover): Two years ago, Neville and Sally asked for permission to look for fossils in a freshly dug quarry.

They never expected to find pieces of bones of several mammoths.

Cup of tea for you, David.

Thank you very much.

There we are.

ATTENBOROUGH: Oh, hang on.

(laughs) Mammoth cake, yeah!

Yeah, so, mammoth cupcakes.

ATTENBOROUGH: Do you have one?

Yes... (laughing) (mumbling) I'm gonna have one.

I'm gonna have a chocolate one.

ATTENBOROUGH (voiceover): But there's one find that raises intriguing questions about how the mammoths died: a stone tool, a hand axe, made by an ancient human.

There was a small glint, and I thought, "Mmm, that looks a bit interesting, a bit different."

ATTENBOROUGH: You saw this?

I just, yeah.

Well, the main thing is that it was made by man.

Yes.

NEVILLE HOLLINGWORTH: Yeah.

And it was that feeling that I was the first human to touch this stone tool in hundreds of thousands of years.

It's a great thrill, isn't it?

It is, yeah.

Yes.

The whole of this business.

ATTENBOROUGH (voiceover): Finding a stone tool near mammoth bones is extremely rare.

But we don't yet know if it was left by humans from a more recent time in prehistory.

Well, you could certainly cut things with that, I'm sure.

SALLY HOLLINGWORTH: Mm.

Yeah, we did.

We did.

You did?

We cut our wedding cake.

(laughing) You cut your wedding cake?

Yes.

(laughs) Yeah.

Really?!

There we are.

(laughing) We cut our wedding cake, got married, and... And had a mammoth meal.

And had a mammoth meal, a mammoth event.

Yeah.

(laughing) Yeah.

ATTENBOROUGH (voiceover): Mammoths roamed the plains of Europe, Asia, and North America until the climate warmed at the end of the last ice age.

These extinct cousins of elephants had huge curving tusks and thrived during the ice age.

Their remains are usually tens of thousands of years old.

But Sally and Neville's finds could be far older.

They could offer an extremely rare glimpse of life deep in the ice age, a time we know little about, when early humans lived alongside mammoths.

But how did these mammoths die?

Was it from natural causes or could they have been hunted?

The quarry where Sally and Neville made their discovery lies just ten miles north of their home in Swindon, near the village of Cerney Wick.

Groundwater was deliberately allowed to flood the site to prevent any bones in the ground from drying out.

Now, two years after they made their first find, that water is being pumped out, ready for a team to begin investigating.

Leading the dig is another husband-and-wife duo, Brendon Wilkins and Lisa Westscott Wilkins.

WESTSCOTT WILKINS: Those ducks must hate us.

They had this place filled with water and now they've got nothing!

ATTENBOROUGH (voiceover): The team starts by mapping the site from the air.

(camera clicking) WESTSCOTT WILKINS: It's so important to record this from the instant that we're doing anything so that we can build that exact picture of how it was before we came along and disturbed it.

ATTENBOROUGH: The drone images provide a detailed map of the site so that the exact location of each find can be plotted.

The team searches for fragments of bone.

Biologist Ben Garrod has been helping coordinate the dig.

That, we think, is mammoth bone, because it's so thick.

Yeah.

Well, it's definitely mammoth.

ATTENBOROUGH: Ben was the first on the team to hear about the site and quickly realized its significance.

GARROD: Sally and Neville got in touch.

And I'd never met them, and they said, "Ben, we found some fossils that I think you might be interested in."

And I said, "Yeah, that's great, send some photos across."

And they did, and I was here the next day.

I jumped on a train and dropped everything and came to the site, and it was like someone had sprinkled mammoth bones everywhere, which I'd, I'd never seen.

I thought I had to go to Siberia to see that.

By looking at this in a forensic level of detail, that'll give us this really in-depth understanding of, of what was going on here whilst these animals and these people were walking around.

ATTENBOROUGH: What intrigued Ben, and me, is why there are so many mammoth bones here from at least four different animals, and the tantalizing mystery of who left that stone tool.

(motor running) So what did the landscape look like when the mammoths were here?

(tool shuts off) KEITH WILKINSON: Okay, up.

ATTENBOROUGH: To find out, geoarchaeologist Keith Wilkinson extracts samples of the underlying sediment.

WILKINSON: So the very bottom, we've got these blue sands.

So they are probably the layer with the, the mammoth fossils in.

We've got these river gravels.

And then these silts and sands at the top of the same ancient river channel.

ATTENBOROUGH: The layers of sediment beneath the surface reveal the bed of a prehistoric river.

This is probably the ancient route of the River Thames, which today lies nearly two miles away.

Could the mammoths have died further upstream and their bones have been washed here when the river flooded?

To find out, the team plots target areas for excavation.

And the digging begins.

They sieve every shovelful of soil in their search for fragments of bone or stone tools.

When the trenches start to reveal new finds, I can't resist stopping by to see how they're doing.

Welcome!

Thank you very much.

What do you think?

Well, I haven't seen it yet!

(laughing) Even I can see that's a tusk!

(laughing) ATTENBOROUGH: Well, let me get it right, where was the head?

So this is our proximal end.

That's the head there.

That's the one, yep.

And that's the tip of the tusk.

Yeah.

So coming round to the tip here.

So it's curving backwards.

Yes.

Exactly.

Exactly, yes.

WESTSCOTT WILKINS: This is possibly a bit of a mandible, this was just found.

So it's a left mandible?

Yep, well, yes.

And, and because we think that might be a left tusk, you know, it's possible that these belonged to the same animal.

WILKINS: You can see bones running into the section there and here, and you can also see a rib bone here.

ATTENBOROUGH: Yeah.

WESTSCOTT WILKINS: One of the things that we wondered with so many of these tusks around, could it have been, did they all fall into the river somewhere... Oh, I see.

...and then get washed down in one big event?

But what we're looking at is not a high-energy environment.

If, if it was a washout, you would expect to see more debris in the channel, more debris in the sediment around the tusks.

But this is basically lying in, in, where it fell.

And the same with the tusk over there.

So we think, you know, they could have just died and fallen.

But it's, it's a bit of a coincidence, really.

ATTENBOROUGH: This pit has been dug out by excavators because until just recently, it was full of gravel down to about this level.

But here is much more solid.

It's not gravel.

It's, it's mud, sticky mud at that, and it's in this undisturbed mud that these bones are now being discovered.

And because it's been undisturbed, very careful excavation can reveal a lot of details about the circumstances in which these animals got here and left their bones.

(voiceover): The most complete bones seem to be lying in the riverbed.

And they've been covered by the fine sediment of slow-moving water, not pounded by fast-moving floodwater.

So perhaps the mammoth died where the bones are lying now.

Spectacular fossils like these have always fascinated us.

Hundreds of years ago, it was thought that mammoth tusks belonged to mythical beasts.

In Siberia, mammoth remains were once thought to be from huge underground burrowing creatures.

In 17th-century Europe, mammoth bones were said to be those of giants, or unicorns.

By the 19th century, mammoths were described as prehistoric animals, but they were thought to have existed long before humans.

Then, in 1864 in France, a piece of mammoth ivory was found with an engraving so accurate, it was clear that the artist had seen a living mammoth.

The engraving shows a woolly mammoth, the most recent species on the mammoth family tree.

We now know that early mammoths first evolved in Africa around five million years ago, and then spread into Europe and Asia.

Around 1.7 million years ago, steppe mammoths evolved that grazed the grassy plains.

They then moved into Europe and North America, where Columbian mammoths later appeared.

The famous woolly mammoths developed around 700,000 years ago, adapted for colder climates, and they eventually spread first into Europe, and then North America.

So which kind of mammoth lived in Britain at our site?

To find out, mammoth evolution expert Steven Zhang is examining the remains found at the site.

The teeth have given him a crucial clue.

ZHANG: Looking at a mammoth tooth is like looking into a barcode for the mammoth itself.

We start by counting the number of enamel ridges, so...

This one has about 18, which is a very typical number for a steppe mammoth.

Looking at this piece of tooth, we know that it's a last molar or a wisdom tooth.

So we know this was a fully grown adult, except this is one of the smallest steppe mammoth teeth there probably is in existence.

It's like finding a German shepherd the size of a Westie.

ATTENBOROUGH: These teeth appear to be from a population of small steppe mammoths.

Their reduced size could be a consequence of food becoming less abundant.

If a steppe mammoth was here now, you would see that it wasn't particularly hairy, a sign that the climate must have been quite temperate.

And as for size, well, the female was about my size, male a bit bigger, and the baby, well, I guess, like that.

Must've been rather enchanting.

(baby elephant squeals, adult lowing) ATTENBOROUGH: There are also remains of another type of mammoth.

ZHANG: Over here, I would say this is a typical woolly mammoth.

So these two different kind of beasts were occurring at the same site.

One possibility was that this site was a habitat shared by both steppe and woolly mammoths, or, as woolly mammoths migrated westward from Siberia into Europe, they started to mingle with local steppe mammoths.

This is interesting, because not often do we see a snapshot like this.

It's exciting!

ATTENBOROUGH: Our site could be rare evidence of a transitional stage, when woolly mammoths are taking over from steppe mammoths.

These bones could have belonged to some of the last surviving steppe mammoths in Britain.

Back at the dig, Sally and Neville have ringside seats as the professionals continue their meticulous search.

NEVILLE HOLLINGWORTH: There is almost a forensic examination of the sediment and everything else.

But that's so they-- that's good, though.

So they don't miss anything.

NEVILLE HOLLINGWORTH: Yeah.

SALLY HOLLINGWORTH: It's like a time travel through the gravel!

I'd like them to solve the story.

Was it hunted?

That's the big question, isn't it?

Yeah, one of the questions.

What was the climate like?

Yeah.

What was the vegetation like?

And also, what else was here?

Not just mammoths, but were there early humans, hominins, wandering about?

Hm.

Were there groups of people, because of the hand axe?

Yes, there were, because we know that there's a hand axe.

ATTENBOROUGH: You have established that there were mammoths here, and there were human beings alongside them, a human being wielding that axe?

I can say at this particular site, there were definitely mammoths, there were definitely human beings-- early human beings, admittedly, but I don't know yet if they were here at the exact same time.

Now, the issue is, it could be like you or I walking on a Viking settlement and dropping a crisp packet.

That's not from the same time period, obviously.

Now, that might have happened here.

I'll let you know in a few months.

ATTENBOROUGH (voiceover): Ben's "few months" becomes two years as COVID lockdowns keep the team away from the site.

But in 2021, they pick up where they left off, this time with some mechanical help.

If only we'd had this last time, it would have just made it so much easier!

The idea at the moment is just to plane down to that level where we've got material that hasn't been disturbed.

ATTENBOROUGH: They clear down to the undisturbed layers and dig new trenches.

Mammoth bones soon begin to appear.

Oh, wow!

That looks good, doesn't it?

Look at that!

GARROD: Wow!

So you got this wonderful little tusk here.

Beautiful, isn't it?

ATTENBOROUGH: To determine the age of these finds, they send sediment samples from the trenches to a specialist lab.

In darkroom conditions, grains of quartz from deep within the sediment are placed in a machine that records tiny levels of radiation.

(machine whirring) The amount of radiation emitted by the grains reveals when they were last exposed to sunlight, and allows the team to estimate the age of the ancient river channel.

Here we've got our distribution of age within our sample.

So, these three age estimates indicate that the channel was formed about 215,000 years ago.

ATTENBOROUGH: Our site dates to a period deep in the ice age.

But the ice age wasn't always icy.

Over the last two-and-a-half million years, huge ice sheets traveled down from the north and then retreated during warmer spells.

The advancing and retreating ice changed the sea level and the coastlines.

But for most of this period, Britain was connected to mainland Europe.

215,000 years ago, when the mammoths were living at our site, conditions were only slightly cooler than today, ideal for a variety of animals.

And evidence of tiny creatures at the site enables us to piece together a portrait of what was growing on this land back then.

JOSH HOGUE: There's loads of small shell fragments throughout this.

We've got this little snail in here.

ATTENBOROUGH: Environmental archaeologist Matt Law carefully identifies samples of tiny, but perfectly preserved, shells.

LAW: We have one land snail in there, so that's a very common species of short grassland snail, and the rest are looking like they're coming from a, a river-type setting.

Well-vegetated, well-oxygenated water, and, but not too much flow, either.

What's really remarkable is the level of preservation.

Not just the snails, but things like beetle remains, seeds, and bits of wood that we don't often see with the level of detail that they are here.

ATTENBOROUGH: The discovery of these species of animals and plants enables us to get a quite detailed picture of what the landscape here was like when the mammoths were roaming around.

This stretch of the ancient Thames was flowing through an open, grassy landscape, a perfect place for large herbivores to feed and find water.

Back at the site, after weeks of searching for more hand axes or stone tools among the mammoth bones, there's been a breakthrough: the telltale signs of humans.

I think this may be a flint artifact.

ATTENBOROUGH: Ben is eager to see the new finds.

It's really over in this area where we're starting to find the really exciting stuff.

Hiding in this sand we have a relatively large piece of mammoth bone sticking from the surface.

And just in the last few days, we've started to pick out just a couple of flints, so, little bits of stone which had been worked by humans.

And they're next door, just 50 centimeters away from this lovely bit of what looks to be a leg bone of a mammoth.

And you can see they'd been taking little chips out of the edge to create a sharp cutting surface, which they could scrape along bones, or along hides, to remove fat.

Something as simple as this starts to connect those, those dots, starts to bring the human story together with the mammoths.

And, and that's really quite special.

ATTENBOROUGH: The presence of these tiny fragments alongside the bone suggests people were here at the same time as the mammoths.

The tool Sally and Neville found could also have been made by the same people.

To find out how these early tools were made, Ben and I arrange to meet Karl Lee, an expert flintknapper.

LEE: So here we go.

(rock clinking, shattering) ATTENBOROUGH (voiceover): Flint is a hard, glassy rock, often found near rivers and beaches.

To shape it, Karl uses a rounded stone and then a piece of antler, just as early humans did.

There we go.

That is amazing.

That is amazing.

Thank you very much.

(chuckles) GARROD: What do you reckon, David?

Could you take down a mammoth with one of those?

I should certainly cut up a deer.

They're around here.

LEE: Yes.

If you killed it with a spear, that's for the butcher.

And, and you butcher it in half-an-hour.

So I have, completely normally, brought a piece of meat on the bone.

LEE: Okay.

ATTENBOROUGH: Gosh.

Huh.

Mind your fingers.

LEE: Yes, mind your fingers.

(chuckles): Thanks, David.

Oh, yeah.

That's gone straight through.

(flint cutting) ATTENBOROUGH: No problem at all.

ATTENBOROUGH (voiceover): Karl also shows us a second method of making stone tools, in which thin shards of flint, known as Levallois flakes, are knocked away from a large flint core.

I have to prepare a platform... ...at the base of the core, and then try and take a nice flake.

Using this method, they're actually planning exactly what that flake's going to look like.

So I'm going to be striking right at the base of the core here, and the flake will hopefully come off on the underside.

That's a brave thing to say.

(chuckles) (flint cracks) That is a Levallois flake.

Now, do watch your fingers on that one, because it's... (blows): It's going to be sharp.

(clears throat) Yes, it's razor-sharp.

Yeah.

Razor-sharp.

Where the edge is so thin, it's translucent-- it looks as though it's all got a halo all around it.

Really beautiful, actually.

LEE: This is a very versatile technology.

It's portable, very lightweight, rather than carrying around something four or five times the weight.

I can't imagine you teaching me this without a really good grasp of language.

Teaching this without language would be, in my opinion, impossible.

And I, my guess would be that children, just as they mimic their parents today, would have been mimicking their parents back then, as well.

(chuckles) So, try and catch it about two millimeters back from the edge, so we... Oh, I've got it, yeah, yeah, yeah, yeah.

That's it, you're away.

ATTENBOROUGH (voiceover): For hundreds of thousands of years, human beings have passed on that sort of skill, that sort of insight into the materials that lay around them.

Of course, they had to be fortunate to find such marvelous material as flint, but once they did, what fabulous things they created with it.

So who were the flint-workers at Cerney Wick?

We know very little about prehistoric people.

Most evidence of their existence has decomposed and disappeared long ago, but their stone tools remain.

They reveal the remarkable story of early species of humans spreading from Africa throughout Northern Europe.

To find out which type of human was living at Cerney Wick, I've come to a secure facility in London.

It holds one of the largest collections of prehistoric artifacts in the world.

Curator Nick Ashton is a renowned expert on these ancient tools.

He begins by showing me simple flint tools found near Happisburgh on the east coast of England.

ASHTON: We know that in Africa they'd been making these tools for some two to three million years.

But this is the earliest evidence that we have in Northern Europe of humans reaching this far north.

Dates to an astonishing 900,000 years ago.

So it's... How much?

900,000 years ago.

Really?

So it's the earliest evidence for humans in Northern Europe.

ATTENBOROUGH: In 2013, Nick's team made a truly extraordinary discovery at Happisburgh.

A storm washed away sand on a beach and revealed ancient footprints set in hardened mud.

They were the oldest human footprints ever documented outside of Africa, but within two weeks, they had vanished, washed away by incoming tides.

It's thought that early humans spread out of Africa around two million years ago.

A million years later, some of their descendants reached Britain.

What sort of people was it who did this?

I mean, did they have clothes of any kind?

Were they covered in hair?

I mean, do we, how, do we know what they looked like?

We, we actually know very little, but the species of human in Europe at that time was Homo antecessor.

They would have looked very similar to ourselves, apart from slightly different facial...

But it's a guess whether they were hairy or not.

It's a guess as to whether they're hairy... (laughs) ...or had extra body fat to cope with these cold winters.

Yeah.

ATTENBOROUGH (voiceover): By 500,000 years ago, humans in Britain were capable of crafting hand axes like the one found at Cerney Wick.

ASHTON: We know that they're hunting by this point, and they're certainly butchering a range of different deer, and probably larger animals, as well.

And one of the important things is, if you're a hunter, you get to the carcass first.

The hide is intact.

It hasn't been chewed to bits by the hyenas or the other carnivores or the big cats.

And that hide you would almost certainly use for either clothing or shelter to help you cope with those cold winters.

ATTENBOROUGH: Humans first used fire in Africa, and by 400,000 years ago, they were using it in Northern Europe, as well.

ASHTON: This is burnt flint.

It's a block of flint that shattered under heat.

What we think we're dealing with is a small campfire, which has all kinds of benefits.

It's not just warm, it's not just keeping away big cats.

It's also a hub for social life.

It extends your daylight hours into the night.

It means you begin to tell stories.

It's all part of the development of language and those all-important social bonds that make us human.

You paint a very, very convincing picture, actually, and anyone who's sat by a fire knows how hypnotic it can be.

ASHTON: Yes.

ATTENBOROUGH: Just sitting there watching the flames.

ASHTON: Yeah, yeah.

ATTENBOROUGH: That's a very exciting picture.

ATTENBOROUGH (voiceover): By 250,000 years ago, Levallois flakes appear like the ones that Karl had shown us.

ASHTON: Here we have these carefully crafted points.

And this is a massive step forward in terms of technology.

ATTENBOROUGH (voiceover): So where does our site fit in?

I've brought Sally and Neville's stone tool.

Now, this, which I know you haven't seen before... What... ...was found alongside this mammoth which we have been excavating.

What does that tell you about dating, or indeed anything else?

Well, it's undoubtedly a hand axe, and very typical of early Neanderthals, quite similar to some of these.

I gather that the site dates to roughly about 200,000 years ago.

So it would actually be contemporary with these Levallois points.

But it's very different.

Here we have a traditional hand axe.

So what's going on?

One idea is that you've got different populations coming in from different parts of Europe with different technologies.

Another idea might be that maybe you've got a residual population in Britain, in Western Britain, who are still making hand axes.

We're still talking about Neanderthals?

We're still talking about Neanderthals.

ATTENBOROUGH (voiceover): Stone tools like these, together with rare fragments of human bone, reveal that four species of human have occupied Britain.

The stone tools and the dating of our site both suggest that the humans who were living here were, in fact, Neanderthals.

To find out more about them, Ben is meeting anthropologist Ella Al-Shamahi.

So our ancestors and the ancestors of Neanderthals were in Africa, and then at some point, a group of them left, and we don't know where and we don't know when.

But they became Neanderthals.

We have sites all the way as far as Siberia, and then we have a whole pile of sites in Europe.

Doesn't mean that they are a European species.

It just means that a lot of the archaeologists are actually in Europe and were digging in their own backyards.

We've got this massive array, actually, of Neanderthals in this whole region.

And if you look at that region, that's a number of different environments, and a number of different climates, as well.

And do we know what they looked like?

Yeah, so Neanderthals were very similar to us, but there were crucial differences.

So, for example, we know that Neanderthals, on average, were, well, they were shorter.

So male Neanderthals would have come in at about five foot four, five foot five.

They were also really stocky.

But, you know, people have said, "Well, if you got a Neanderthal, "you gave him a shave, and you give him a bowler hat, you put him on the New York subway, would anyone notice?"

And then somebody else obviously said, "Well, that probably says more about the New York subway than it does about Neanderthals."

(laughs) But the point stands, you know.

How different were they, really?

ATTENBOROUGH: Back at the site, the team is finding that nearly all the tusks and bones are lying in a single layer of sediment, suggesting the mammoths all died around the same time.

What could have killed a group of mammoths in such a short period?

WILKINSON: And we can trace this layer pretty much all the way around to the tusk on the far side, now.

So it's, they're all...

It's all the, formed at the same time.

And we can't see flooding?

'Cause I'm just trying to think what's, what's forcible enough to move a tusk.

No, there's nothing, I mean...

This is, this is weird, 'cause there's not enough mud.

There's not enough, there's no flood.

No.

They just died in this area for some reason.

Yeah.

ATTENBOROUGH: Ben is doubtful that the mammoth got stuck in the mud.

GARROD: The mud's deep, but it's not up to a mammoth's armpits deep.

Disease?

I mean, there's nothing, really, in terms of, of modern relatives, that-- the elephants-- that would kill a whole group that quickly in one site at one time to explain this.

And we've got adults and juveniles, as well.

So it's not the classic elephant graveyard all, all being left in one site, either.

And it leaves this idea, this possibility, that it was people.

So were they chasing them in?

Were they corralling them somehow?

Were they-- I, I don't know.

But that's almost weirder, because I can't imagine quite early Neanderthal people bringing down a bunch of mammoths.

Because these things were tons of anger and intelligence.

ATTENBOROUGH: Evidence suggesting that Neanderthals could successfully hunt mammoths is extremely rare.

But this is the island of Jersey, and here, at La Cotte de St. Brelade, piles of mammoth bones have been found that suggest that Neanderthals may indeed have been killing mammoths here.

Archaeologist Matt Pope has been studying the site for years.

POPE: Our first glimpse of La Cotte de St. Brelade, towering up above us.

GARROD: Oh, wow, It's like this huge cathedral fortress, isn't it?

It's beautiful.

POPE: We can see a lot of the site from here, the main granite structure, the arch that takes you through to the north ravine, and in front of us, the west ravine, the main open space.

ATTENBOROUGH: The site has been investigated since 1881.

And over the years, archaeologists excavated down into the ravine.

At two levels, they discovered heaps of bones of butchered mammoths.

The mystery is how these bones got there.

POPE: An original explanation, and a very good one, was that the mammoth were all herded together, by Neanderthal hunters, and driven over the cliffs to their death.

So you imagine... GARROD: From right up there?

POPE: From right up there.

I mean, that's quite a thought, to think of a whole herd of mammoths coming cascading over the edge right there.

POPE: It's a good theory, but it's not a very good headland for actually concentrating a herd.

There is simply no way you could funnel the mammoth into this ravine.

They'd be splitting off into all different directions.

We've been recently relooking at those bone heaps and looking at the evidence, and we put forward an alternative idea.

And that idea is that these bone heaps didn't form in one go... Mm-hmm.

...in mass kills.

But actually, they formed over a long period of time, and the hunting was taking place out here on the surrounding landscapes.

They were bringing these bones back, and then over time, they put these heaps of bone together.

And this whole area, as we look at it now, it's this beautiful coastline that stretches out to the, the Channel here.

But this would have all been one big grassy plain.

POPE: We've got the seabed landscape mapped.

There's little cul-de-sacs where you get dead ends, and you could control game.

And we know from other Neanderthal sites where hunting is taking place, they love landscapes in which they control game.

Probably the whole Neanderthal community would be involved in hunting, corralling, controlling, moving, isolating particular members of a herd.

ATTENBOROUGH: Most archaeologists now think that the Neanderthals were capable of hunting large prey like mammoths, as they seem to have done in Jersey.

But it would be much harder to trap them on the flat grasslands of Cerney Wick.

Perhaps the river might have slowed the mammoths down.

But how would the Neanderthals have killed them?

Wooden spears may well have been used.

Wood, of course, rots away quickly, so we're very unlikely to find one.

But there are some.

In 1911, in Essex, a wooden spear tip was found in waterlogged soil.

And in 1948, stronger evidence of spear hunting was uncovered.

A spear was found within the fossilized ribs of a straight-tusked elephant.

Then, in 1995, at a mine in Schningen in Germany, ten miraculously well preserved Neanderthal spears were found lying among the skeletons of around 50 horses, the oldest complete prehistoric hunting weapons ever found.

Archaeologists had assumed these early hunters thrust their spears into the flanks of prey at close range.

But could spears like this have been thrown at mammoths from a longer distance?

To find out, we asked a wood carver to make exact replicas of the Schningen spears from spruce, the same shape, weight, and type of wood as the ancient spears.

MILKS: Hi, guys.

GARROD: We've brought you some spears.

ATTENBOROUGH: Annemieke Milks is an investigator of Neanderthal hunting methods.

She wants to see how well these replica Neanderthal spears will perform in the hands of Bekah Walton and Harry Hughes, two of Britain's leading javelin throwers.

I'm really curious to see what an experienced thrower makes of how they feel.

WALTON: They are the right length, compared to a normal spear.

Yeah, the balance is really good.

Yeah, they're surprisingly similar to a normal javelin, actually.

Yeah.

ATTENBOROUGH: Annemieke wants to test how the spears fly, and if they can be used accurately, to hit a target.

GARROD: We want to know, can you two kill that mammoth silhouette for us, please?

HUGHES: Okay, right, should we give it a go?

WALTON: Let's go.

(Garrod chortling) WALTON: Oh, my gosh.

First time.

MILKS: Up until fairly recently, most people were arguing that Neanderthals were only capable of hunting at immediate distances.

And this shows that their technology was capable of distance hunting.

(Garrod chortles) MILKS: Brilliant.

GARROD: Okay, big question of the day.

Our site, is there any chance that our Neanderthals could have been hunting mammoths, do you think?

Given the fact that we have a whole load of evidence that the spears are functional weapons-- both as thrusting weapons and as throwing weapons-- and that we see this evidence of exploitation of mammoth, I think it's very much in the realm of possibility that mammoths were being hunted by Neanderthals with spears like these.

ATTENBOROUGH: So Neanderthals could possibly have hunted mammoths at Cerney Wick over 200,000 years ago.

But in the millennia that followed, both the Neanderthals and the steppe mammoths disappeared.

Neanderthals resettled in Britain around 60,000 years ago.

But our own species, Homo sapiens, arrives soon after that, and evidence of the presence of Neanderthals vanishes.

AL-SHAMAHI: It might be that we out-competed them, right?

We were just better at using the landscape and resources.

One of the things that we know is that they lived in small, isolated populations.

That is not going to do your gene pool any good.

Hm.

At all.

There's even an argument that they're still with us today.

Me and you will have about two percent Neanderthal DNA in us.

And that's because our ancestors-- multiple times, it seems-- interbred with Neanderthals.

So actually, the end of the story isn't completely tragic, because it turns out that there's a little bit of them...

Still here.

In us, yeah.

ATTENBOROUGH: Back at the site at Cerney Wick, there's excitement as they assess their haul of flint tools.

(laughing): Are you okay?

Are you okay?

Breathe-- I think he forgot to breathe.

Wow, wow.

This, this lovely little flake.

So you can see it's got a little point where they hit it with a stone hammer to remove it.

WESTSCOTT WILKINS: It's perfect.

WILKINS: Wow, and that was the first hint that you found?

That was the first one, yeah.

WILKINS: So there was a party straight after that?

And then the next one we found... WILKINS: Oh, my goodness.

...is this beautiful scraper edge.

Typically we think, you know, you would have held it like this.

WESTSCOTT WILKINS: Look how it fits.

They would have pulled the fat off of the hide.

It's really quite impressive.

We've got these five flint tools all from the same area, all finely worked, all really, really clear.

And that's quite exciting and quite rare.

I mean, it's really easy to say, "Oh, five things.

That's not many."

But actually, when we're talking about 200,000 years ago, we might only be finding one or two things in a site which has been excavated for decades.

ATTENBOROUGH: On the mammoth leg bone they found next to the flints, they've seen scratch marks that could provide evidence of butchery.

HOGUE: We see little marks and nicks... WILKINS: Yeah.

...in the top.

HOGUE: Two lovely parallel lines.

There's one slightly longer.

WILKINS: Yeah.

There's another one, just a short one, just in beside it.

Yeah.

And it's really tempting to call them cut marks, but we'll have to get it back into the lab to actually determine.

Yeah.

It's like a really big whodunit, isn't it?

Mm-hmm.

So, did they all die of a disease?

Was there a massive flood that came in?

Or were we hunting them?

Having worked with elephants in the wild, I think possibly, a juvenile, very, very young one might have just got stuck in the mud.

It panicked the group.

Things went really badly really quickly, and we came along as scavengers and possibly found the world's biggest buffet lying there for us.

We're just opportunists, is what you're saying.

GARROD: I think we were opportunists.

HOGUE: Well, I just love the idea that the, you know, Neanderthals are sitting on the ridge over the far end, hiding amongst the tall grass.

And then mammoths are coming down to the water and they're panicking them.

Neanderthals come in and they take advantage of, of the mammoths, they sort of start butchering and taking away the nice meat for meals.

GARROD: Isn't it wonderful to think that the last time someone sat exactly on this spot in a little group with that stone tool in their hands was 200,000 years ago, as a mammoth lying just over there?

WILKINS: Wow.

And here we are talking about it... Yeah, they were about to have their lunch.

...hundreds of thousands of years later.

Yeah.

It's quite poignant, isn't it?

WILKINS: Yeah, absolutely.

It really is.

ATTENBOROUGH: The evidence paints a tantalizing picture of ice age Britain: an ancient River Thames flowing through grassland; a group of some of the last steppe mammoths in Britain; and Neanderthals using flint tools to butcher mammoth meat.

Whether or not they hunted the mammoths requires more evidence, but at this site, it certainly looks as if something extraordinary happened: Neanderthals feasting on mammoth on the banks of the River Thames.

At the end of the dig and before the area is flooded again, we invite Sally and Neville to return to the site so that we can show them what the scene might once have looked like.

SALLY HOLLINGWORTH: Okay.

GARROD: We've prepared something where... (exhales): You don't have to use your imagination to, to visualize this area.

If I give these to you...

Okay, cool.

Thank you.

Put them on, make sure they're comfy, and enjoy.

Righty-ho.

(squeals): Mammoth!

(laughing) Oh, that is just incredible.

SALLY HOLLINGWORTH: Oh, my God, that's amazing.

ATTENBOROUGH: The finds at this remarkable site have given us a rare glimpse of early Britain.

A time when humans were fully immersed in the wild, living as part of nature.

It's thought that Neanderthals may have been around for some 400,000 years.

Their survival relied on their understanding of the natural world.

Whether our own species can thrive for quite as long remains to be seen.