-
2. Mountains
Human
beings venture into the highest parts of our
planet at their peril. Some might
think
that by climbing a great mountain they have
somehow conquered it, but we can
only
be visitors here. This is a frozen alien world.
This is the other extreme - one of
the
lowest hottest places on Earth. It'sover a hundred
metres below the level of the sea.
But
here a mountain is in gestation. Pools of
sulphuric acid are indications that deep
underground
there
are
titanic
stirrings.
This
is
the
Danakil
Depression
in
Ethiopia,
lying within a
colossal rent of the earth's surface where giant
land masses are pulling
away
from
one
another.
Lava
rises
to
the
surface
through
this
crack
in
the
crust
creating
a
chain
of
young
volcanoes.
This
one,
Erta
Ale,
is
today
the
longest
continually
erupting
volcano
on
the
planet,
a
lake
of
lava
that
has
been
molten
for
over a hundred years. These same
volcanic forces also created Ethiopia's highlands.
70 million years ago this land was just
as flat and as deep as the Danakil Depression.
Molten
lava
rising
from
the
earth's
core
forced
up
a
huge
dome
of
rock
500
miles
wide, the roof of Africa. Over
millennia, rain and ice carved the rock into a
landscape
of
spires
and
canyons.
These
summits,
nearly
3
miles
up,
are
home
to
some
very
remarkable
mountaineers
Gelada
baboons.
They
are
unique
to
the
highlands
of
Ethiopia.
The
cliffs
where
they
sleep
are
for
expert
climbers
only,
and
Gelado
certainly have the right equipment. the
strongest fingers of any primate and an utterly
fearless disposition. But you need more
than a head for heights to survive up here. A
day
in
a
Gelado's
life
reveals
how
they've
risen
to
the
challenge.
For
all
monkeys
morning
is
grooming
time,
a
chance
to
catch
up
with
friends.
But,
unlike
other
monkeys,
Gelados
chatter
constantly
while
they
do
it.
It's
a
great
way
to
network
while your hands are
these socials can't go on for too long. Gelados
have a
busy daily schedule and there's
work to be done. Most monkeys couldn't live up
here.
There's no food and few insects
to feed on. But Gelados are unique they're the
only
monkeys
in
the
world
that
live
almost
entirely
on
grass.
They
live
in
the
largest
assemblies formed by any monkeys. Some
groups
are 800 strong and they crop the
high
meadows
like
herds
of
wildebeest.
The
Gelados
graze
alongside
Walia
ibex,
which are also unique
to these highlands. These rare creatures are
usually very shy but
they
drop
their
guard
when
the
Gelados
are
around.
You
might
expect
that
grazers
would avoid each
other's patch but this is a special alliance from
which both partners
benefit. It's not
so risky to put your head down if others are on
the lookout. Ethiopian
wolves
-
they
won't
attempt
an
attack
in
broad
daylight.
But
at
dusk
the
plateau
becomes a more dangerous place. With
the grazing largely over there's a last chance
to
socialise
before
returning
to
the
sleeping
cliffs.
An
early
warning
system
puts
everyone
on
the
alert.
Their
day
ends
as
it
began,
safe
on
the
steep
cliffs.
The
Ethiopian volcanoes are dormant, but
elsewhere others still rage. Volcanoes form the
backbone of the longest mountain chain
on our planet - the Andes of South America.
This
vast
range
stretches
5,000
miles
from
the
Equator
down
to
the
Antarctic.
It
formed as the floor of the Pacific
Ocean slid beneath the South American continent,
buckling
its
edge.
At
the
southern
end
stand
the
mountains
of
Patagonia.
It's
high
summer,
but
the
Andeshave
the
most
unstable
mountain
weather
on
the
planet
and
storms
can
erupt
without
warning.
Temperatures
plummet
and
guanacos
and
their
newborn
young must suddenly endure a blizzard.
Truly, all seasons
in
one
day...
A
puma - the lion of
the Andes. Pumas are usually solitary and
secretive. To see a group
walking
boldly in the open is extremely rare. It's a
family - a mother with four cubs.
She
has
just
one
brief
summer
in
which
to
teach
them
their
mountain
survival
techniques. Rearing four cubs to this
age is an exceptional feat, but she does have an
excellent territory, rich in food and
water. Although the cubs are now as large as their
mother, they still rely on her for
their food. It will be another year before the
cubs can
hunt
for
themselves.
Without
their
mother's
skill
and
experience
they
would
never
survive
their
first
winter.
Battered
by
hurricane
force
winds,
these
slopes
are
now
lifeless.
Further
north,
they
hold
other
dangers.
Moving
at
250
miles
an
hour,
an
avalanche
destroys
everything
in
its
path.
In
the
American
Rockies
a
100,000
avalanches devastate the slopes every
winter. This huge mountain chain continues the
great
spine
that
runs
from
Patagonia
to
Alaska.
The
slopes
of
the
Rockies,
bleak
though they are, provide a winter
refuge for some animals. A mother grizzly emerges
from her den after six months' dozing
underground. Her two cubs follow her and take
their first steps in the outside world.
These steep slopes provide a sanctuary for the
cubs. A male bear would kill and eat
them given the chance. But big animals findit
difficult to get about here. Males may
be twice the size of a female and even she can
have problems. Her cubs, however, make
light of the snow and of life in general. But
the mother faces a dilemma: it's six
months since she last fed and her milk is starting
to run dry. She must soon leave the
safety of these nursery slopes and lead her cubs
away from the mountain. If she delays,
the whole family will risk starvation. Summer
reveals the true nature of the Rockies.
Stripped of snow, the peaks bear their sculpted
forms.
Only
now
can
mountaineers
reclaim
the
upper
reaches.
Two
miles
up
the
crumbling precipices seem devoid of
life. But there are animals here - a grizzly bear.
It seems to be an odd creature to find
on these high rocky slopes. It's hard to imagine
what could have attracted it here. At
this time of the year bears should be fattening up
for the winter. Yet
they
gather in
some numbers on
these
apparently
barren
slopes.
They're searching for a rather
unusual food - moths. Millions have flown up here
to
escape the heat of the lowlands and
they're now roosting among the rocks. Moths may
seem a meager meal for a bear, but
their bodies are rich in fat and can make all the
difference in a bear's annual struggle
for survival. Another battle is being waged here
but on a much longer timescale. These
loose boulders are the mountain's crumbling
bones.
The
Rockies
are
no
longer
rising
but
slowly
disintegrating.
All
mountains
everywhere are being worn down by
frost, snow and ice. The Alps were raised some
15 million years ago as Africa,
drifting northwards,collided with the southern
edge of
Europe. These spires are the
eroded remains of an ancient seabed that once
stretched
between the two continents.
But these are just the Alpine foothills. The range
at its
centre rises to 3 miles high and
is crowned with permanent snows. The Matterhorn,
its
summit
too
steep
to
hold
a
snow
field.
Mont
Blanc
-
the
highest
peak
in
Western
Europe.
The
distinctive
jagged
shapes
of
the
Alps
were
carved
by
those
great
mountain
sculptors
-
the
glaciers.
Immense
rivers
of
moving
ice,
laden
with
rock,
grind
their
way
down
the
mountains,
gouging
out
deep
valleys.
They're
the
most
powerful
erosive force on our planet.
A moulin
-
a
shaft
in
the ice opened by
melt
water as it plunges into the
depths of the glacier. Like the water running
through it,