Woolly Mammoth: Secrets from the Ice Page #5

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and offload oxygen.

But what about at low temperatures?

Yeah, so as temperatures went down,

the abilities diverged.

So as temperature got lower

and lower,

mammoth haemoglobin, we found,

was more able to offload oxygen

than that of the Asian elephant,

and far better than that of humans.

It is incredible to be able

to take ancient DNA

and to resurrect

a protein from the past.

A protein which hasn't existed

in a living animal

for thousands of years,

and once we have this protein

we can look at how it behaves.

Mammoth haemoglobin can deliver

oxygen at very low temperatures,

meaning that mammoths could

let their legs,

their extremities GET cold.

And they could then

hold on to their body heat,

and conserve energy through the

long cold winters of the ice age.

It was crucial to survival.

'These new molecular level

investigations are bringing

'the science-fiction

style possibility

'of cloning a mammoth ever closer. '

'In the far east of Siberia

an incredible new discovery

'is being heralded as the holy

grail of mammoth science.

'In the city of Yakutsk, members of

the International Mammoth Committee

'have unearthed a completely intact

frozen mammoth thigh bone.

'Although thousands of years old,

'it's one of the best

preserved bone specimens

'retrieved from the permafrost.

'So perfectly frozen that it

contains pure mammoth bone marrow.

'This could be the best source

ever of fully intact mammoth cells,

'with undamaged DNA.'

THEY TALK IN JAPANESE

'The marrow will be sent to a lab in

Japan where they will try to extract

intact cell nuclei, and insert them

in to a host elephant egg.

'If successful,

'scientists there predict that they

will be able to clone a mammoth

'by using a female elephant as a

surrogate mother within five years. '

'But the ethics of creating

such a clone

'is likely to kick up

a storm of debate.

'Should scientists even be

attempting

'to resurrect an extinct species?

'Rather than trying to clone

a long-dead species,

'many scientists are far more eager

to understand why the mammoths

'died out in the first place. '

'Their extinction coincided

with the warming climate

'at the end of the ice age.

'The environment they'd perfectly

adapted to was changing.

'The blue skies that created

the steppe grew heavy with cloud.

'Rain returned to the North.

'Dry grassland was replaced with

wet tundra plants and forests,

'the mammoths' favoured food

supply was dwindling.

'But the genetic studies completed

recently,

'suggest that woolly mammoths

'had coped well with similar

changes in the past.

'A population crash occurred,

'30,000 years before they finally

disappeared.

'But they recovered,

suggesting that something else,

'other than changing habitat may

have spelt the end. '

The mammoth had survived through

many fluctuations in the climate,

through all of these warming

and cooling cycles,

why was it at the

very end of the ice age

that they seemed to give up?

It might not have been

an all-or-nothing process,

that it's just depending

on this one last cycle.

It might actually have been

a gradual process that after

every warming and cooling period,

that not only the population

numbers but also the diversity

of the animals went down.

'Professor Dan Fisher thinks

he might now have the answer.

'After analysing hundreds

of ancient tusks

'from different mammoth species,

'he's uncovered a pattern suggesting

'that mammoths were being

increasingly hunted

'by predators as the climate grew

warmer, and their numbers dwindled. '

So, you've obviously seen

changes in lots of tusks

that you think are evidence of

predation pressure.

So, what are those changes,

what was going on in these

mammoth populations?

The changes that we see

that seem best

explained by increases

in predation pressure,

are things like maturation at a

younger age, calving intervals,

or intervals between calves in

females

that are, if anything, shorter,

in other words these are changes

that are reasonable responses

to a changing balance of risk

between survival and reproduction.

It's better if there's more

predation going on

to reproduce a little bit earlier,

even if it's smaller body size.

And to have a few more calves,

even if there's less investment

in individual calves.

It's a better bet, so to speak,

in the long run to have that

kind of a life history in a regime

of higher incidence of predation.

So I think the evidence is that

human hunting was an extremely

important aspect of what drove

the extinction.

'If Dan Fisher is right it's a huge

step forward

'in explaining mammoths' extinction.

'He's sure mammoths were maturing

fast and having babies early towards

'the end of the ice age, a classic

sign that they were being hunted.

'But in Siberia, the evidence that,

that predation was by man is scarce.

'Now potential new evidence

has surfaced.

'Dan's colleague,

mammoth hunter Bernard Buigues,

'thinks he might have made a new

discovery which could support

'the idea that humans hunted

mammoths to extinction.

'In a secret location on the edges

of the Arctic Ocean,

'thousands of miles away from where

I first met him, he's recovered

'a new specimen, which was found

frozen in the banks of a river.

'He's suggesting it shows

signs of human interaction

'this could be a missing

link in the human/mammoth puzzle. '

CHATTER:

'I seize the chance to witness such

a find and fly back to Siberia

'to meet Bernard, who's transporting

the mammoth

'across the frozen tundra.

'We agree to rendezvous in the

remote wilderness of Yakutia. '

Well, this is it,

this is the rendezvous point.

And I know they're on their way,

I can't hear anything yet though.

But it is incredibly cold.

I hope it's worth it.

They're bringing this mammoth in,

they're going to eventually

take it to Yakutsk,

and we'll be able to have

a look at it there,

and hopefully it will be

another piece of the puzzle.

It will add to our understanding

of these ancient creatures

that once roamed around this

landscape.

Oh, I think I can see them.

Can you see the lights over there,

on the horizon?

They've just crested the hill.

Oh this is fantastic,

it's just so exciting.

Bernard! Oh, my God!

You've done it.

Yeah, yeah, yeah.

Oh my goodness,

and where's the mammoth?

The mammoth is

laying like this yeah,

he's on the back with

the four legs up,

and it's a young mammoth.

Yeah, it's smaller than I expected.

It's a wonderful specimen,

you will see. I want to show you.

Oh, fantastic. I want to show.

Oh, that's brilliant.

I want to share with you.

All right, lovely.

'We board an ex-military

transporter plane

'to travel a further

'where we'll start the analysis

of the mammoth

'in a permafrost ice cave.

'Will this frozen carcass reveal

any clues to help explain

'the mammoth's extinction?'

I can't wait to see it,

it's travelled all this distance.

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