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Few babies have such a compressed childhood
as this young elephant seal

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born on a beach in Patagonia
only a few days ago.

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Its mother can't feed out of water,
so she won't stay here for long,

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and her pup has to suck the milk
it needs from her as quickly as it can.

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The milk contains twelve times
more fat than cow's milk.

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The mother produces it directly from her blubber,

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and the pup converts most of it
straight back to blubber.

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The nursery is dangerously crowded,

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and pups can easily be crushed
and killed by the huge bulls

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as they quarrel and chase after the females.

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After only three weeks,
the pup has quadrupled its birth weight.

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But its mother is now starving.
She has to get back to the sea.

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So now this pup is on its own.

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And it'll remain here
for another six to eight weeks

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while it converts the fat it took on
so urgently from its mother

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into flesh and bone

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and gets strong enough to go out to sea.

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And that task of gaining size and strength

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sufficient to survive unaided

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is the main task of childhood.

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And the main trial of childhood
is avoiding danger and remaining alive

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during this difficult period
when an animal is almost defenceless.

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Baby terns need fish,

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and their parents bring it to them
several times a day.

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They too grow up in a crowded nursery,

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for all terns in the colony start laying
almost simultaneously in the late spring,

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when days are beginning to lengthen

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and there is more time for the adults
to catch the large quantities of fish

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they need to satisfy their ravening young.

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The nests are so tightly packed together

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that returning parents inevitably invade
the airspace of their neighbours

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and there's a lot of squabbling.

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The very density of the colony,
however, brings one great advantage.

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Gulls, if they get a chance,

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will snatch and swallow an egg or a chick.

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A single tern has little chance of driving them off.

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But a group can mount
a much more formidable defence.

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You might think that parental responsibility
would hardly trouble an insect.

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Most, having laid their eggs, abandon them.

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But not the female lacebug.

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She protects her newly-hatched young

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It stabs the young lacebug
with its stiletto mouthparts

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and sucks it dry.

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But in its death-throes,
the infant bug raises the alarm.

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It discharges a smell that summons the mother.

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What weapons she has to fight
such an enemy is difficult to see.

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Nonetheless, she wins,

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and shepherds her charges away
to feed elsewhere.

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But there is always danger.

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A jumping spider.

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0nce again, back into battle.

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Her hard wing cases seem to protect her
from the spider's poison fangs,

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but even so, it's a brave display.

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Even a spider, apparently, can be seen off

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if you have the courage of motherhood.

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In the Russian Arctic,
at the beginning of the brief summer,

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snow geese babies are hatching.

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Their thick down protects them from the cold

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and they instinctively peck for food

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almost as soon as they're free from their shells.

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But they don't wander far from their parents,

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for like all ducks, geese
and many ground-living birds,

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they become fixated on the first
large moving things they see.

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Those are nearly always the legs of their parents,

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and they will follow them throughout childhood.

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So when mother and father move on,
they all move on.

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An Arctic fox.

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When the geese started nesting
a month ago, the coast was icebound.

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Now the ice has melted, and the family
starts the long journey to the sea,

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where they can find food.

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If they can, they float.

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But most of the journey has to be done on foot,

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for the young can't fly
and their parents won't desert them.

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And that is real devotion,
for the coast is 30 miles away.

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That imprinted compulsion to follow mother's legs

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and stay near the protection of her beak

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will never be more important.

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And of course,
the parents must always be prepared

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to fight off enemies.

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0nce again, gulls.

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A mother goose can produce
as many as ten goslings

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because, like all birds, she lays eggs.

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As one develops, she expels it from her body,
securely wrapped in a shell.

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No bird could retain a dozen
developing chicks inside her body

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and still fly.

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Mammals bear their young in a different way.

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Their babies do develop inside their mother's body

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and emerge alive and without shells.

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Even so, some mammals are able
to produce huge litters.

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Here in Florida, in the United States,

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there lives one species
that gives birth to its young

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in a way which is quite different
from that of any other mammal

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in North America or indeed in Europe.

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There is one in this tree here.

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Its closest cousins are in South America,

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but most of its relatives are found in Australia.

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It's an opossum.

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A female opossum -
this one is South American -

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gives birth to her babies
when they are hardly as big as bees.

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She may produce as many as 50 of them.

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They wriggle out of her body,
clamber through her fur,

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and fasten themselves on to nipples
in a pouch on her underside.

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But she has only about a dozen teats.

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First come, first served - the rest die.

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The lucky ones stay attached,
drinking away for the next 16 weeks.

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Even when they are able to take solid food

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and are big enough to find it for themselves,

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they are very reluctant indeed to leave Mother.

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She seems commendably
attentive and affectionate,

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but they are undoubtedly
a great encumbrance to her

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and by now she's been caring
for them for four months.

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It's time they left.

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Here, in my shirt...is a baby.

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The mother abandons all her babies
when they get to about this stage,

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and they creep about in the forest,
quite defenceless,

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so they can be easily picked up, like this.

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In Australia, kangaroos and wallabies

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also rear their babies in pouches
from a very early stage.

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But they only produce one at a time

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and they look after them for much longer.

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A young wallaby doesn't leave
the pouch at all for about five months.

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Towards the end of that time,
it's so big and heavy

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that if its mother is hopping downhill,

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she may turn it out so that
she isn't tripped up by it.

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Even when the baby has emerged,
it keeps returning,

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clearly reluctant to leave, and understandably so.

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In the pouch, it can get the best of both worlds -
milk inside and vegetables outside.

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Mammals of the northern hemisphere,

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like these central Asian antelope, the saiga,

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keep their young within their bodies
until they are very well developed.

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A young saiga, within minutes of its arrival,

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is able to stagger to its feet - but only just.

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And it must keep going.

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Its mother has to move with the herd
to get her food - grass,

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and the baby has to move
with its mother to get its food - milk.

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The young are born in May,
when the thin grass is beginning to sprout

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and the need for the herd
to keep moving is least urgent.

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If the calf is lucky, it may be allowed to spend
a couple of days in a scrape on the ground

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before it has to move.

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But it may have to be
up and running within hours.

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A severe winter on these bleak plains
can decimate a herd.

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But saiga can recover their numbers
with extraordinary speed.

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A female calf, born in the spring,

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can mate in the autumn
when she is not even fully grown,

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and bear her first single baby the next spring.

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The following year, when she's adult,

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she usually produces twins.

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So a herd that has been almost wiped out

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can be 100,000 strong again
within a few years.

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The steppe eagle is hardly big enough

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to take a young vigorous saiga calf.

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It's mostly a carrion feeder,

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but if the baby saiga weakens,
the eagle will finish it off.

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As the days warm, the herd moves north,
following the retreating snow

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and feeding on the newly-sprouting grass
as it's exposed.

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But within a few months,
the cold begins to return

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and parents and young
will have to trek back again.

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By the time the young saiga is a year old,

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it may have walked as much
as 6,000 kilometres - almost 4,000 miles.

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Baby scorpions get a lift.

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Their mother has no permanent home
and wanders over quite a wide range,

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as most hunters must do if they're to find prey.

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As soon as they hatch,
they clamber up on to the mother's back.

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There's no safer place for them

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than beneath the formidable sting
on the end of her tail.

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A mother shrew parks her babies,

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hiding them in a safe place,
often under a stone.

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Having herself fed on insects,
she comes back to feed them on milk.

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But if she's alarmed and suspects
that her nursery has become unsafe,

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she gives her young -
whose eyesight is not very good -

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a command with an ultrasonic squeak

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which we can't hear,
but which they obey immediately.

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Among eider duck, looking after
the young is a job for females.

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The black and white males take no part in it.

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The females, however, share the load.

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Mothers lead their newly-hatched
ducklings down to the sea.

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There, other females, aunties,
take charge of them,

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allowing the mothers who haven't fed
since they started incubating a month ago

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to go off and get a good meal.

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These aunties are young females
who haven't paired this season

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and who have no young of their own.

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More and more families come down to the water,

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until the nursery - the cr�che -

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may have as many as 500 ducklings in it.

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The young ducklings are perfectly
able to feed themselves,

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finding lots of small creatures
in the surface waters,

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but they are completely defenceless,
and once again there are enemies around.

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The gull make a test flight
to assess the defences of the cr�che

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and finds that aunties can be
just as brave as any parent.

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Even though the gull
is driven off and gets nothing,

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there are inevitably casualties.

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This is a mara,
a Patagonian relative of the guinea pig,

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and it too uses a cr�che.

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A dozen or so females
give birth in the same place,

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so there may be as many
as 40 young maras in one nursery hole.

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Although no one adult
is permanently in charge like an auntie,

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there are nearly always
one or two parents around,

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for mammals can't abandon their young
for days on end as eider ducks can.

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Each mother has to return daily
to give her babies milk.

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Her aim is to feed only her babies -
usually twins.

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She recognises them largely by their smell.

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That doesn't stop others in the nursery
from trying their luck.

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Even when her twins have got to her,

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the rest will try and steal a drink if they can.

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Sometimes the whole cr�che
pester a mother so vigorously

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that if she is young and inexperienced

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she may just give up and allow
any and all of them to take her milk.

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Some bats also use the cr�che system.

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All these are females, free-tailed bats

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00:23:45,526 --> 00:23:49,360
that flew up to this cave in Texas
from Mexico a few weeks ago,

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leaving their mates to their own devices.

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The cave is a perfect maternity ward for them.

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It's warm and dry

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and the surrounding countryside
is rich in insects to feed on.

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00:24:02,726 --> 00:24:06,958
But there aren't many caves like it,
so it's intensely crowded.

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A million mothers chose this one,

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and now there are a million
newborn babes here as well.

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In the late afternoon, the mothers leave to feed.

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The departure starts before it's properly dark,

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for it takes a long time for a million bats

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to stream out
of the relatively small cave mouth.

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The babies they leave behind
are massed in one huge cr�che.

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It was important for them to cluster together
when they were first born and naked

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in order that they should keep warm.

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Even now, when they're beginning
to grow their fur,

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staying together saves energy.

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00:25:27,566 --> 00:25:30,638
But imagine trying to find your baby
among this lot.

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Throughout the night, mothers visit
the cr�che to feed their babies milk.

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This mother knows the layout
of the cave well enough

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to have landed quite close
to where she left her baby,

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but a lot of jostling goes on here,

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and the baby may have moved a yard or so.

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00:25:57,006 --> 00:25:58,564
As she searches,

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00:25:58,726 --> 00:26:02,401
other hungry youngsters struggle
to reach the nipples in her armpits

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and steal a drink.

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No luck. She gives up.

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00:26:33,566 --> 00:26:38,560
If a baby doesn't get a proper feed
at least once a night, it's likely to die.

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00:26:39,486 --> 00:26:42,717
So she returns and starts again.

239
00:26:53,646 --> 00:26:55,159
0n the edge of the cr�che,

240
00:26:55,326 --> 00:26:59,524
a youngster waits for its mother,
who hasn't returned for some time.

241
00:27:00,206 --> 00:27:04,165
And below, scavengers wait
for corpses that might fall.

242
00:27:14,806 --> 00:27:18,515
The mother's main way of finding
her baby is, astonishingly,

243
00:27:18,686 --> 00:27:22,599
by recognising its cry -
even in this pandemonium.

244
00:27:37,326 --> 00:27:40,238
At last. This is her baby.

245
00:27:40,406 --> 00:27:42,397
And at last it feeds.

246
00:27:55,126 --> 00:27:57,117
Vast nurseries like this one

247
00:27:57,286 --> 00:28:00,642
can only exist if there's
an abundance of food around.

248
00:28:01,246 --> 00:28:03,601
Not far from Texas, in Florida,

249
00:28:03,766 --> 00:28:06,041
the situation is very different.

250
00:28:11,646 --> 00:28:14,319
The white sand on which
these scrubby pines grow

251
00:28:14,486 --> 00:28:18,718
is so poor in nutrients
that there's little to sustain adult animals,

252
00:28:18,886 --> 00:28:20,399
let alone their babies.

253
00:28:20,566 --> 00:28:23,683
Even birds find it a hard place in which to live.

254
00:28:24,526 --> 00:28:28,201
Food is hard to find and there aren't
many places to build a nest,

255
00:28:28,366 --> 00:28:30,960
but it's the home of an interesting bird

256
00:28:31,126 --> 00:28:35,199
that has been studied almost as intensively
as any bird in the world.

257
00:28:35,806 --> 00:28:37,239
And this is it!

258
00:28:38,206 --> 00:28:40,322
The Florida scrub jay.

259
00:28:40,486 --> 00:28:43,876
Every jay in this part of the world
has been banded

260
00:28:44,046 --> 00:28:45,957
for the past almost 20 years.

261
00:28:46,126 --> 00:28:49,562
We know who each one is
and how they fit into the community.

262
00:28:49,726 --> 00:28:54,561
This one, with three rings
on her right leg, is a young female.

263
00:28:54,726 --> 00:28:58,605
She was hatched last year
on the territory to the left here.

264
00:29:00,206 --> 00:29:04,324
This one, with bands on both legs,
is, in fact... 0ops!

265
00:29:04,486 --> 00:29:09,162
..the dominant male,
who has a nest in this territory.

266
00:29:15,126 --> 00:29:19,244
Food is so scarce that more than two
adults are needed to search for it

267
00:29:19,406 --> 00:29:22,204
if a nestful of chicks is to be kept supplied.

268
00:29:22,366 --> 00:29:25,517
This bird is not the parent of these nestlings.

269
00:29:25,686 --> 00:29:30,282
It's one of last year's chicks
who's helping to raise this year's brood.

270
00:29:32,646 --> 00:29:35,206
Young female helpers, after a year or two,

271
00:29:35,366 --> 00:29:38,244
usually leave to look for territories of their own,

272
00:29:38,406 --> 00:29:42,081
but young males may stay on
for as long as seven years.

273
00:29:42,246 --> 00:29:46,239
0ne of them may inherit
the family estate and nesting site

274
00:29:46,406 --> 00:29:48,397
when the old breeding male dies,

275
00:29:48,566 --> 00:29:51,126
but most will never father a brood.

276
00:29:51,286 --> 00:29:53,277
Instead of producing their own young,

277
00:29:53,446 --> 00:29:55,596
they find their reproductive reward

278
00:29:55,766 --> 00:29:58,485
in helping to raise their brothers and sisters.

279
00:30:16,206 --> 00:30:19,915
Guarding the food supply
is just as important as collecting it,

280
00:30:20,086 --> 00:30:22,919
and some of the helpers act as sentinels...

281
00:30:23,966 --> 00:30:26,400
keeping an eye out for thieves.

282
00:30:32,566 --> 00:30:35,524
This is a trespasser
from a neighbouring territory,

283
00:30:35,686 --> 00:30:37,961
sneaking in to try and steal food.

284
00:30:40,766 --> 00:30:43,041
That can't be allowed.

285
00:30:46,126 --> 00:30:49,277
(AGGRESSIVE SQUAWKING)

286
00:31:07,406 --> 00:31:09,397
Back to normal duties.

287
00:31:11,206 --> 00:31:14,164
Another intruder - an indigo snake.

288
00:31:14,326 --> 00:31:15,884
It too is hungry,

289
00:31:16,046 --> 00:31:19,800
and the meal it is searching for
could well be a jay chick.

290
00:32:07,326 --> 00:32:10,443
So teamwork saves the nest.

291
00:32:10,606 --> 00:32:12,324
Indeed, as a result of studies here,

292
00:32:12,486 --> 00:32:16,001
we now know that pairs
with teams to help them

293
00:32:16,166 --> 00:32:19,522
are much more successful
in rearing their young.

294
00:32:19,686 --> 00:32:22,405
Recently, it has been discovered
that this form of co-operation

295
00:32:22,566 --> 00:32:24,557
is quite widespread among birds.

296
00:32:24,726 --> 00:32:27,718
Some species of wrens
and woodpeckers and moorhens

297
00:32:27,886 --> 00:32:33,358
all use this form of co-operation under some
circumstances, as indeed do some mammals.

298
00:32:36,966 --> 00:32:40,925
Elephants, for example,
collaborate to bring up their babies -

299
00:32:41,086 --> 00:32:43,042
at least, the females do.

300
00:32:43,206 --> 00:32:45,595
The males, when they become adult,
wander off

301
00:32:45,766 --> 00:32:48,724
and live more or less
solitary lives away from the herd.

302
00:32:53,566 --> 00:32:57,081
A new baby is the focus
of great interest and affection,

303
00:32:57,246 --> 00:33:01,125
not only from its mother,
but from elder sisters, aunts,

304
00:33:01,286 --> 00:33:04,403
and especially the old lady
who leads the herd,

305
00:33:04,566 --> 00:33:07,285
who is almost certainly its grandmother.

306
00:33:30,046 --> 00:33:35,279
Sometimes, indeed, everyone wants
to have the privilege of being nanny.

307
00:34:04,966 --> 00:34:08,322
This visiting bull is not used to infants.

308
00:34:13,326 --> 00:34:16,636
Great consternation among sisters and aunts.

309
00:34:33,286 --> 00:34:36,198
Childhood, of course, is a time for play,

310
00:34:36,366 --> 00:34:39,802
and play is a way of finding out
about the world around you

311
00:34:39,966 --> 00:34:43,117
and acquiring the skills you may need later.

312
00:35:10,046 --> 00:35:14,961
Playing in water is fun
not only for infants, but for adults.

313
00:35:15,126 --> 00:35:18,038
It's a pleasure that elephants
never seem to lose,

314
00:35:18,206 --> 00:35:20,197
no matter how old they are.

315
00:35:23,126 --> 00:35:25,765
Still, it takes a bit of getting used to.

316
00:35:48,206 --> 00:35:51,323
And how do you get your legs clean afterwards?

317
00:36:16,646 --> 00:36:19,479
Elephants have a very long childhood.

318
00:36:19,646 --> 00:36:25,243
Most don't reach the age of puberty
until they're 11 or 12 years old.

319
00:36:27,486 --> 00:36:29,204
As they approach that time,

320
00:36:29,366 --> 00:36:33,279
they begin to try out
some of the things that adults do.

321
00:37:12,886 --> 00:37:16,162
An elephant doesn't need to be a fast learner.

322
00:37:16,326 --> 00:37:20,797
It's a strict vegetarian
and the range of food it collects is small.

323
00:37:20,966 --> 00:37:23,560
It doesn't have to worry unduly about enemies -

324
00:37:23,726 --> 00:37:27,639
its great bulk as an adult is protection in itself.

325
00:37:28,126 --> 00:37:30,879
And if you live for 60 or 70 years,

326
00:37:31,046 --> 00:37:33,480
then there's no great hurry to grow up

327
00:37:33,646 --> 00:37:35,682
and assume adult responsibilities.

328
00:37:35,846 --> 00:37:38,758
And, in any case, it takes time to build a body

329
00:37:38,926 --> 00:37:42,123
that will eventually weigh five tons or so.

330
00:37:43,566 --> 00:37:46,797
Chimpanzee childhood is more complicated.

331
00:37:46,966 --> 00:37:49,924
Chimps feed on a wide variety of things,

332
00:37:50,086 --> 00:37:53,283
and a youngster must know
what's good to eat and what isn't.

333
00:37:53,446 --> 00:37:56,836
They're very excitable animals,
with a complex social life,

334
00:37:57,006 --> 00:38:01,955
so a young chimp must learn how to behave
towards different individuals,

335
00:38:02,126 --> 00:38:06,119
and there are all kinds
of physical skills to be acquired.

336
00:38:11,126 --> 00:38:15,165
The baby spends the first few months
of its life clinging to its mother.

337
00:38:15,326 --> 00:38:17,920
From this privileged and protected position,

338
00:38:18,086 --> 00:38:22,045
it has a grandstand view of what's
going on and how things are done.

339
00:38:23,646 --> 00:38:27,275
These particular chimps,
living in the Ivory Coast forest,

340
00:38:27,446 --> 00:38:30,119
have devised a special skill all of their own.

341
00:38:30,286 --> 00:38:32,356
They've learned how to crack nuts.

342
00:38:32,526 --> 00:38:35,245
These are now a favourite part of their diet.

343
00:38:35,406 --> 00:38:37,840
But when you're only nine months old,

344
00:38:38,006 --> 00:38:42,522
watching mother crack nuts
loses its fascination after a bit.

345
00:38:43,486 --> 00:38:47,035
The shells, on the other hand,
have possibilities as toys.

346
00:39:06,046 --> 00:39:08,241
(CHIMPS SHRIEK)

347
00:39:13,126 --> 00:39:15,435
You also need to learn pretty quickly

348
00:39:15,606 --> 00:39:20,475
who is likely to be your friend
and who it's safer to steer clear of.

349
00:39:34,206 --> 00:39:37,676
This older infant is beginning
to follow the big boys

350
00:39:37,846 --> 00:39:39,643
and copy the way they behave,

351
00:39:39,806 --> 00:39:42,798
so discovering what life is like
among the grown-ups.

352
00:39:52,406 --> 00:39:56,399
And Mother is always there
to provide comfort and protection

353
00:39:56,566 --> 00:39:59,399
when things get a bit baffling and worrisome.

354
00:40:29,126 --> 00:40:31,879
Nut cracking is a complicated business

355
00:40:32,046 --> 00:40:35,482
and involves some of the most
advanced tool-using techniques

356
00:40:35,646 --> 00:40:37,637
practised by any animal.

357
00:40:42,326 --> 00:40:45,318
It's no use just bashing a stick on the ground.

358
00:40:45,486 --> 00:40:47,681
You have to have a decent anvil.

359
00:41:06,806 --> 00:41:08,797
Nuts have to be collected

360
00:41:08,966 --> 00:41:11,685
and then carried to where they can be cracked.

361
00:41:31,126 --> 00:41:34,835
The anvil is almost always the root of a tree.

362
00:42:29,326 --> 00:42:33,842
Eventually, the time comes when,
at last, you get the hang of things.

363
00:42:41,126 --> 00:42:45,438
For chimpanzees, acquiring
adult skills is a gradual process,

364
00:42:45,606 --> 00:42:48,245
but that is not the case for most animals.

365
00:42:49,886 --> 00:42:54,323
For these baby albatross
on the Leeward Islands in the Pacific,

366
00:42:54,486 --> 00:42:57,603
the ending of childhood is brutally abrupt.

367
00:42:57,766 --> 00:43:00,280
Within the next few days, they must fly

368
00:43:00,446 --> 00:43:04,917
and almost immediately become
as accomplished in the air as their parents,

369
00:43:05,086 --> 00:43:07,281
who fly so effortlessly above them.

370
00:43:14,726 --> 00:43:19,117
The best they can do to prepare
is to strengthen their breast muscles

371
00:43:19,286 --> 00:43:20,924
by beating their wings.

372
00:43:31,326 --> 00:43:33,635
If they don't get it right first time,

373
00:43:33,806 --> 00:43:36,036
the results could be catastrophic -

374
00:43:36,206 --> 00:43:39,084
in the shallows, dark shapes have appeared.

375
00:44:25,326 --> 00:44:26,805
Tiger sharks.

376
00:44:26,966 --> 00:44:30,675
Every year, at this precise time,
they appear from nowhere.

377
00:46:14,046 --> 00:46:16,640
For the bats too, in the cave in Texas,

378
00:46:16,806 --> 00:46:18,922
childhood is coming to an end.

379
00:46:19,086 --> 00:46:21,646
The babies are now over a month old,

380
00:46:21,806 --> 00:46:26,357
and the time is coming for their mothers
to join the males in Mexico

381
00:46:26,526 --> 00:46:28,756
and take their babies with them.

382
00:46:33,566 --> 00:46:35,204
For the past few days,

383
00:46:35,366 --> 00:46:39,917
many babies have been going
on practise flights within the cave,

384
00:46:40,086 --> 00:46:43,965
but now some of them
are accompanying the adult females

385
00:46:44,126 --> 00:46:46,879
as they fly out into the open sky.

386
00:46:47,046 --> 00:46:49,685
But they're far from expert fliers.

387
00:46:49,846 --> 00:46:53,839
Here's one that has crash-landed
within a few yards of the cave.

388
00:46:56,126 --> 00:46:58,720
When he was in the cave, he was very safe -

389
00:46:58,886 --> 00:47:02,674
about one in a hundred babies die in there -

390
00:47:02,846 --> 00:47:05,918
but out here, he is surrounded by danger.

391
00:47:06,086 --> 00:47:10,284
0f the million bats that were born
five weeks ago in there,

392
00:47:10,446 --> 00:47:14,439
three quarters will be dead before they're adult.

393
00:47:14,606 --> 00:47:16,164
So for this little creature,

394
00:47:16,326 --> 00:47:20,842
the trials of life really are
just starting. Good luck to you.

395
00:47:20,892 --> 00:47:25,442
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