Few babies have such a compressed childhood as this young elephant seal
born on a beach in Patagonia only a few days ago.
Its mother can't feed out of water, so she won't stay here for long,
and her pup has to suck the milk it needs from her as quickly as it can.
The milk contains twelve times more fat than cow's milk.
The mother produces it directly from her blubber,
and the pup converts most of it straight back to blubber.
The nursery is dangerously crowded,
and pups can easily be crushed and killed by the huge bulls
as they quarrel and chase after the females.
After only three weeks, the pup has quadrupled its birth weight.
But its mother is now starving. She has to get back to the sea.
So now this pup is on its own.
And it'll remain here for another six to eight weeks
while it converts the fat it took on so urgently from its mother
into flesh and bone
and gets strong enough to go out to sea.
And that task of gaining size and strength
sufficient to survive unaided
is the main task of childhood.
And the main trial of childhood is avoiding danger and remaining alive
during this difficult period when an animal is almost defenceless.
Baby terns need fish,
and their parents bring it to them several times a day.
They too grow up in a crowded nursery,
for all terns in the colony start laying almost simultaneously in the late spring,
when days are beginning to lengthen
and there is more time for the adults to catch the large quantities of fish
they need to satisfy their ravening young.
The nests are so tightly packed together
that returning parents inevitably invade the airspace of their neighbours
and there's a lot of squabbling.
The very density of the colony, however, brings one great advantage.
Gulls, if they get a chance,
will snatch and swallow an egg or a chick.
A single tern has little chance of driving them off.
But a group can mount a much more formidable defence.
You might think that parental responsibility would hardly trouble an insect.
Most, having laid their eggs, abandon them.
But not the female lacebug.
She protects her newly-hatched young
with as much diligence and courage as any tern.
This is one of her many enemies - the larva of a lacewing.
It stabs the young lacebug with its stiletto mouthparts
and sucks it dry.
But in its death-throes, the infant bug raises the alarm.
It discharges a smell that summons the mother.
What weapons she has to fight such an enemy is difficult to see.
Nonetheless, she wins,
and shepherds her charges away to feed elsewhere.
But there is always danger.
A jumping spider.
0nce again, back into battle.
Her hard wing cases seem to protect her from the spider's poison fangs,
but even so, it's a brave display.
Even a spider, apparently, can be seen off
if you have the courage of motherhood.
In the Russian Arctic, at the beginning of the brief summer,
snow geese babies are hatching.
Their thick down protects them from the cold
and they instinctively peck for food
almost as soon as they're free from their shells.
But they don't wander far from their parents,
for like all ducks, geese and many ground-living birds,
they become fixated on the first large moving things they see.
Those are nearly always the legs of their parents,
and they will follow them throughout childhood.
So when mother and father move on, they all move on.
An Arctic fox.
When the geese started nesting a month ago, the coast was icebound.
Now the ice has melted, and the family starts the long journey to the sea,
where they can find food.
If they can, they float.
But most of the journey has to be done on foot,
for the young can't fly and their parents won't desert them.
And that is real devotion, for the coast is 30 miles away.
That imprinted compulsion to follow mother's legs
and stay near the protection of her beak
will never be more important.
And of course, the parents must always be prepared
to fight off enemies.
0nce again, gulls.
A mother goose can produce as many as ten goslings
because, like all birds, she lays eggs.
As one develops, she expels it from her body, securely wrapped in a shell.
No bird could retain a dozen developing chicks inside her body
and still fly.
Mammals bear their young in a different way.
Their babies do develop inside their mother's body
and emerge alive and without shells.
Even so, some mammals are able to produce huge litters.
Here in Florida, in the United States,
there lives one species that gives birth to its young
in a way which is quite different from that of any other mammal
in North America or indeed in Europe.
There is one in this tree here.
Its closest cousins are in South America,
but most of its relatives are found in Australia.
It's an opossum.
A female opossum - this one is South American -
gives birth to her babies when they are hardly as big as bees.
She may produce as many as 50 of them.
They wriggle out of her body, clamber through her fur,
and fasten themselves on to nipples in a pouch on her underside.
But she has only about a dozen teats.
First come, first served - the rest die.
The lucky ones stay attached, drinking away for the next 16 weeks.
Even when they are able to take solid food
and are big enough to find it for themselves,
they are very reluctant indeed to leave Mother.
She seems commendably attentive and affectionate,
but they are undoubtedly a great encumbrance to her
and by now she's been caring for them for four months.
It's time they left.
Here, in my shirt...is a baby.
The mother abandons all her babies when they get to about this stage,
and they creep about in the forest, quite defenceless,
so they can be easily picked up, like this.
In Australia, kangaroos and wallabies
also rear their babies in pouches from a very early stage.
But they only produce one at a time
and they look after them for much longer.
A young wallaby doesn't leave the pouch at all for about five months.
Towards the end of that time, it's so big and heavy
that if its mother is hopping downhill,
she may turn it out so that she isn't tripped up by it.
Even when the baby has emerged, it keeps returning,
clearly reluctant to leave, and understandably so.
In the pouch, it can get the best of both worlds - milk inside and vegetables outside.
Mammals of the northern hemisphere,
like these central Asian antelope, the saiga,
keep their young within their bodies until they are very well developed.
A young saiga, within minutes of its arrival,
is able to stagger to its feet - but only just.
And it must keep going.
Its mother has to move with the herd to get her food - grass,
and the baby has to move with its mother to get its food - milk.
The young are born in May, when the thin grass is beginning to sprout
and the need for the herd to keep moving is least urgent.
If the calf is lucky, it may be allowed to spend a couple of days in a scrape on the ground
before it has to move.
But it may have to be up and running within hours.
A severe winter on these bleak plains can decimate a herd.
But saiga can recover their numbers with extraordinary speed.
A female calf, born in the spring,
can mate in the autumn when she is not even fully grown,
and bear her first single baby the next spring.
The following year, when she's adult,
she usually produces twins.
So a herd that has been almost wiped out
can be 100,000 strong again within a few years.
The steppe eagle is hardly big enough
to take a young vigorous saiga calf.
It's mostly a carrion feeder,
but if the baby saiga weakens, the eagle will finish it off.
As the days warm, the herd moves north, following the retreating snow
and feeding on the newly-sprouting grass as it's exposed.
But within a few months, the cold begins to return
and parents and young will have to trek back again.
By the time the young saiga is a year old,
it may have walked as much as 6,000 kilometres - almost 4,000 miles.
Baby scorpions get a lift.
Their mother has no permanent home and wanders over quite a wide range,
as most hunters must do if they're to find prey.
As soon as they hatch, they clamber up on to the mother's back.
There's no safer place for them
than beneath the formidable sting on the end of her tail.
A mother shrew parks her babies,
hiding them in a safe place, often under a stone.
Having herself fed on insects, she comes back to feed them on milk.
But if she's alarmed and suspects that her nursery has become unsafe,
she gives her young - whose eyesight is not very good -
a command with an ultrasonic squeak
which we can't hear, but which they obey immediately.
Among eider duck, looking after the young is a job for females.
The black and white males take no part in it.
The females, however, share the load.
Mothers lead their newly-hatched ducklings down to the sea.
There, other females, aunties, take charge of them,
allowing the mothers who haven't fed since they started incubating a month ago
to go off and get a good meal.
These aunties are young females who haven't paired this season
and who have no young of their own.
More and more families come down to the water,
until the nursery - the créche -
may have as many as 500 ducklings in it.
The young ducklings are perfectly able to feed themselves,
finding lots of small creatures in the surface waters,
but they are completely defenceless, and once again there are enemies around.
The gull make a test flight to assess the defences of the créche
and finds that aunties can be just as brave as any parent.
Even though the gull is driven off and gets nothing,
there are inevitably casualties.
This is a mara, a Patagonian relative of the guinea pig,
and it too uses a créche.
A dozen or so females give birth in the same place,
so there may be as many as 40 young maras in one nursery hole.
Although no one adult is permanently in charge like an auntie,
there are nearly always one or two parents around,
for mammals can't abandon their young for days on end as eider ducks can.
Each mother has to return daily to give her babies milk.
Her aim is to feed only her babies - usually twins.
She recognises them largely by their smell.
That doesn't stop others in the nursery from trying their luck.
Even when her twins have got to her,
the rest will try and steal a drink if they can.
Sometimes the whole créche pester a mother so vigorously
that if she is young and inexperienced
she may just give up and allow any and all of them to take her milk.
Some bats also use the créche system.
All these are females, free-tailed bats
that flew up to this cave in Texas from Mexico a few weeks ago,
leaving their mates to their own devices.
The cave is a perfect maternity ward for them.
It's warm and dry
and the surrounding countryside is rich in insects to feed on.
But there aren't many caves like it, so it's intensely crowded.
A million mothers chose this one,
and now there are a million newborn babes here as well.
In the late afternoon, the mothers leave to feed.
The departure starts before it's properly dark,
for it takes a long time for a million bats
to stream out of the relatively small cave mouth.
The babies they leave behind are massed in one huge créche.
It was important for them to cluster together when they were first born and naked
in order that they should keep warm.
Even now, when they're beginning to grow their fur,
staying together saves energy.
But imagine trying to find your baby among this lot.
Throughout the night, mothers visit the créche to feed their babies milk.
This mother knows the layout of the cave well enough
to have landed quite close to where she left her baby,
but a lot of jostling goes on here,
and the baby may have moved a yard or so.
As she searches,
other hungry youngsters struggle to reach the nipples in her armpits
and steal a drink.
No luck. She gives up.
If a baby doesn't get a proper feed at least once a night, it's likely to die.
So she returns and starts again.
0n the edge of the créche,
a youngster waits for its mother, who hasn't returned for some time.
And below, scavengers wait for corpses that might fall.
The mother's main way of finding her baby is, astonishingly,
by recognising its cry - even in this pandemonium.
At last. This is her baby.
And at last it feeds.
Vast nurseries like this one
can only exist if there's an abundance of food around.
Not far from Texas, in Florida,
the situation is very different.
The white sand on which these scrubby pines grow
is so poor in nutrients that there's little to sustain adult animals,
let alone their babies.
Even birds find it a hard place in which to live.
Food is hard to find and there aren't many places to build a nest,
but it's the home of an interesting bird
that has been studied almost as intensively as any bird in the world.
And this is it!
The Florida scrub jay.
Every jay in this part of the world has been banded
for the past almost 20 years.
We know who each one is and how they fit into the community.
This one, with three rings on her right leg, is a young female.
She was hatched last year on the territory to the left here.
This one, with bands on both legs, is, in fact... 0ops!
..the dominant male, who has a nest in this territory.
Food is so scarce that more than two adults are needed to search for it
if a nestful of chicks is to be kept supplied.
This bird is not the parent of these nestlings.
It's one of last year's chicks who's helping to raise this year's brood.
Young female helpers, after a year or two,
usually leave to look for territories of their own,
but young males may stay on for as long as seven years.
0ne of them may inherit the family estate and nesting site
when the old breeding male dies,
but most will never father a brood.
Instead of producing their own young,
they find their reproductive reward
in helping to raise their brothers and sisters.
Guarding the food supply is just as important as collecting it,
and some of the helpers act as sentinels...
keeping an eye out for thieves.
This is a trespasser from a neighbouring territory,
sneaking in to try and steal food.
That can't be allowed.
(AGGRESSIVE SQUAWKING)
Back to normal duties.
Another intruder - an indigo snake.
It too is hungry,
and the meal it is searching for could well be a jay chick.
So teamwork saves the nest.
Indeed, as a result of studies here,
we now know that pairs with teams to help them
are much more successful in rearing their young.
Recently, it has been discovered that this form of co-operation
is quite widespread among birds.
Some species of wrens and woodpeckers and moorhens
all use this form of co-operation under some circumstances, as indeed do some mammals.
Elephants, for example, collaborate to bring up their babies -
at least, the females do.
The males, when they become adult, wander off
and live more or less solitary lives away from the herd.
A new baby is the focus of great interest and affection,
not only from its mother, but from elder sisters, aunts,
and especially the old lady who leads the herd,
who is almost certainly its grandmother.
Sometimes, indeed, everyone wants to have the privilege of being nanny.
This visiting bull is not used to infants.
Great consternation among sisters and aunts.
Childhood, of course, is a time for play,
and play is a way of finding out about the world around you
and acquiring the skills you may need later.
Playing in water is fun not only for infants, but for adults.
It's a pleasure that elephants never seem to lose,
no matter how old they are.
Still, it takes a bit of getting used to.
And how do you get your legs clean afterwards?
Elephants have a very long childhood.
Most don't reach the age of puberty until they're 11 or 12 years old.
As they approach that time,
they begin to try out some of the things that adults do.
An elephant doesn't need to be a fast learner.
It's a strict vegetarian and the range of food it collects is small.
It doesn't have to worry unduly about enemies -
its great bulk as an adult is protection in itself.
And if you live for 60 or 70 years,
then there's no great hurry to grow up
and assume adult responsibilities.
And, in any case, it takes time to build a body
that will eventually weigh five tons or so.
Chimpanzee childhood is more complicated.
Chimps feed on a wide variety of things,
and a youngster must know what's good to eat and what isn't.
They're very excitable animals, with a complex social life,
so a young chimp must learn how to behave towards different individuals,
and there are all kinds of physical skills to be acquired.
The baby spends the first few months of its life clinging to its mother.
From this privileged and protected position,
it has a grandstand view of what's going on and how things are done.
These particular chimps, living in the Ivory Coast forest,
have devised a special skill all of their own.
They've learned how to crack nuts.
These are now a favourite part of their diet.
But when you're only nine months old,
watching mother crack nuts loses its fascination after a bit.
The shells, on the other hand, have possibilities as toys.
(CHIMPS SHRIEK)
You also need to learn pretty quickly
who is likely to be your friend and who it's safer to steer clear of.
This older infant is beginning to follow the big boys
and copy the way they behave,
so discovering what life is like among the grown-ups.
And Mother is always there to provide comfort and protection
when things get a bit baffling and worrisome.
Nut cracking is a complicated business
and involves some of the most advanced tool-using techniques
practised by any animal.
It's no use just bashing a stick on the ground.
You have to have a decent anvil.
Nuts have to be collected
and then carried to where they can be cracked.
The anvil is almost always the root of a tree.
Eventually, the time comes when, at last, you get the hang of things.
For chimpanzees, acquiring adult skills is a gradual process,
but that is not the case for most animals.
For these baby albatross on the Leeward Islands in the Pacific,
the ending of childhood is brutally abrupt.
Within the next few days, they must fly
and almost immediately become as accomplished in the air as their parents,
who fly so effortlessly above them.
The best they can do to prepare is to strengthen their breast muscles
by beating their wings.
If they don't get it right first time,
the results could be catastrophic -
in the shallows, dark shapes have appeared.
Tiger sharks.
Every year, at this precise time, they appear from nowhere.
For the bats too, in the cave in Texas,
childhood is coming to an end.
The babies are now over a month old,
and the time is coming for their mothers to join the males in Mexico
and take their babies with them.
For the past few days,
many babies have been going on practise flights within the cave,
but now some of them are accompanying the adult females
as they fly out into the open sky.
But they're far from expert fliers.
Here's one that has crash-landed within a few yards of the cave.
When he was in the cave, he was very safe -
about one in a hundred babies die in there -
but out here, he is surrounded by danger.
0f the million bats that were born five weeks ago in there,
three quarters will be dead before they're adult.
So for this little creature,
the trials of life really are just starting. Good luck to you.