0:01:05 > 0:01:10Few babies have such a compressed childhood as this young elephant seal,
0:01:10 > 0:01:13born on a beach in Patagonia only a few days ago.
0:01:20 > 0:01:26Its mother can't feed out of water, so she won't stay here for long,
0:01:26 > 0:01:31and her pup must suck the milk it needs as quickly as it can.
0:01:31 > 0:01:34LOUD GRUNTING
0:01:40 > 0:01:47The milk contains 12 times more fat than cow's milk.
0:01:47 > 0:01:56The mother produces it from her blubber and the pup converts most of it straight back to blubber.
0:01:56 > 0:02:03The nursery is dangerously crowded and the pups can easily be crushed and killed by the huge bulls
0:02:03 > 0:02:09as they quarrel among themselves and chase after the females.
0:02:10 > 0:02:15In three weeks, the pup's weight has quadrupled.
0:02:15 > 0:02:20But its mother is now starving and has to get back to the sea.
0:02:20 > 0:02:23So now this pup is on its own.
0:02:23 > 0:02:28It will remain here for another six to eight weeks
0:02:28 > 0:02:36while it converts the fat that it took so urgently from its mother into flesh and bone
0:02:36 > 0:02:40and gets strong enough to go out to sea.
0:02:40 > 0:02:47And that task of gaining size and strength sufficient to survive unaided
0:02:47 > 0:02:50is the main task of childhood.
0:02:50 > 0:02:55And the main trial of childhood is to remain alive
0:02:55 > 0:03:01during this difficult period when an animal is almost defenceless.
0:03:01 > 0:03:06CHIRPING OF MANY CHICKS
0:03:06 > 0:03:14Baby terns need fish, and their parents bring it to them several times a day.
0:03:28 > 0:03:31Their nursery is crowded, too,
0:03:31 > 0:03:37for all terns in the colony start laying almost simultaneously in late spring,
0:03:37 > 0:03:44when there is more time to catch the quantities of fish the young need.
0:03:53 > 0:03:58The nests are so tightly packed together
0:03:58 > 0:04:04that returning parents inevitably invade their neighbours' airspace
0:04:04 > 0:04:07and there's a lot of squabbling.
0:04:34 > 0:04:40But the very density of the colony brings one great advantage.
0:04:40 > 0:04:47Gulls, if given a chance, will snatch and swallow an egg or a chick.
0:04:47 > 0:04:52A single tern has little chance of driving them off,
0:04:52 > 0:04:57but a group can mount a much more formidable defence.
0:06:09 > 0:06:14You may think that parental responsibility
0:06:14 > 0:06:17would hardly trouble an insect.
0:06:17 > 0:06:22Most DO abandon their eggs, but not the female lace-bug.
0:06:22 > 0:06:29She protects her newly-hatched young with as much diligence and courage as any tern.
0:06:29 > 0:06:35This is one of her many enemies - the larva of a lacewing.
0:06:35 > 0:06:41It stabs the young lace-bug with its stiletto mouth-parts
0:06:41 > 0:06:44and sucks it dry.
0:06:44 > 0:06:47But in its death throes,
0:06:47 > 0:06:52the infant bug raises the alarm - it discharges a smell
0:06:52 > 0:06:55that summons the mother.
0:06:55 > 0:07:03What weapons she has with which to fight such an enemy is difficult to see.
0:07:06 > 0:07:09Nonetheless, she wins
0:07:09 > 0:07:13and shepherds her charges away
0:07:13 > 0:07:16to feed elsewhere.
0:07:35 > 0:07:38But there is always danger...
0:07:38 > 0:07:41A jumping spider.
0:07:41 > 0:07:44Once again, back into battle.
0:07:51 > 0:07:59Her hard wing-cases seem to give some protection from the spider's poison fangs,
0:07:59 > 0:08:02but even so it is a brave display.
0:08:14 > 0:08:19Even a spider, apparently, can be seen off
0:08:19 > 0:08:24if you have the courage of motherhood.
0:08:26 > 0:08:33In the Russian Arctic, at the start of the brief summer, snow geese babies are hatching.
0:08:41 > 0:08:46Their thick down protects them from the cold
0:08:46 > 0:08:51and they instinctively peck for morsels of food
0:08:51 > 0:08:56almost as soon as they are free from their shells.
0:08:58 > 0:09:03But they don't wander far from their parents,
0:09:03 > 0:09:08for like all ducks, geese and many ground-living birds,
0:09:08 > 0:09:16they become fixated on the image of the first large moving things they see.
0:09:16 > 0:09:21These are nearly always the legs of their parents,
0:09:21 > 0:09:26and they will follow them for the rest of their childhood.
0:09:26 > 0:09:31So when mother and father move on, they ALL move on.
0:09:55 > 0:09:58An Arctic fox.
0:10:01 > 0:10:04GEESE HONK ANGRILY
0:10:15 > 0:10:20When the geese started nesting last month, the coast was ice-bound.
0:10:20 > 0:10:23But now the ice has melted and the family start off
0:10:23 > 0:10:27on a long journey to the sea, where they can find food.
0:10:27 > 0:10:30If they can, they float.
0:10:32 > 0:10:35But most of the journey has to be done on foot,
0:10:35 > 0:10:39for the young can't fly and their parents won't desert them.
0:10:39 > 0:10:43And that is real devotion, for the coast is 30 miles away.
0:10:45 > 0:10:52That imprinted compulsion to follow mother's legs will never be more important.
0:10:55 > 0:10:58CONSTANT CHIRPING
0:11:04 > 0:11:10And, of course, the parents must always be prepared to fight off enemies.
0:11:10 > 0:11:14Once again, gulls.
0:11:59 > 0:12:05A mother goose can produce as many as ten goslings because she lays eggs.
0:12:05 > 0:12:10As one develops, she expels it from her body, wrapped in a shell.
0:12:10 > 0:12:17No bird could retain a dozen chicks inside her body and still fly.
0:12:17 > 0:12:22Mammals, of course, bear their young in a different way.
0:12:22 > 0:12:30Their babies DO develop inside their mother's body and emerge alive, without shells.
0:12:30 > 0:12:35Even so, some mammals produce huge litters.
0:12:35 > 0:12:44Here in Florida, there lives one species which gives birth to its young in a quite unique way.
0:12:44 > 0:12:47There's one in this tree here.
0:12:47 > 0:12:53Most of its relatives are found in Australia.
0:12:53 > 0:12:56It's an opossum.
0:12:57 > 0:13:02A female opossum gives birth
0:13:02 > 0:13:06when her babies are hardly as big as bees.
0:13:06 > 0:13:09She may produce as many as 50.
0:13:09 > 0:13:14They wriggle out and fasten on to her nipples.
0:13:14 > 0:13:20But she has only about a dozen teats. First come, first served. The rest die.
0:13:20 > 0:13:28The lucky ones stay attached, drinking away for the next 16 weeks.
0:13:28 > 0:13:35Even when they can take solid food and are big enough to find it for themselves,
0:13:35 > 0:13:38they are reluctant to leave mother.
0:13:38 > 0:13:43She's attentive and affectionate, but they are a great encumbrance.
0:13:43 > 0:13:49By now, she's been caring for them for four months. It's time they left.
0:13:51 > 0:13:54And here in my shirt
0:13:54 > 0:13:57is a baby.
0:13:57 > 0:14:02The mother abandons ALL her babies when they get to about this stage,
0:14:02 > 0:14:06and they creep about, quite defenceless,
0:14:06 > 0:14:09so they can be easily picked up.
0:14:13 > 0:14:18Kangaroos and wallabies also rear their babies in pouches.
0:14:18 > 0:14:27But they only produce one at a time and they look after them for much longer.
0:14:27 > 0:14:34A young wallaby doesn't leave the pouch at all for about five months.
0:14:34 > 0:14:37Towards the end of that time,
0:14:37 > 0:14:43it's so heavy that mother may tip it out so as not to be tripped up by it.
0:14:43 > 0:14:52Even when the baby HAS emerged, it's still reluctant to leave - understandably so.
0:14:52 > 0:14:58In the pouch it can get milk inside and vegetables outside.
0:14:58 > 0:15:06Mammals of the northern hemisphere, like these Central Asian antelope, the saiga,
0:15:06 > 0:15:12keep their young within them until they're very well developed.
0:15:12 > 0:15:20A young saiga, within minutes of its arrival, is able to stagger to its feet...but only just.
0:15:24 > 0:15:27BLEATING
0:15:27 > 0:15:30And it MUST keep going.
0:15:30 > 0:15:36Its mother must move with the herd to get her food, grass,
0:15:36 > 0:15:45and the baby has to move with its mother to get its food, milk.
0:15:45 > 0:15:47The young are born in May,
0:15:47 > 0:15:55when the grass begins to sprout and the need for the herd to keep moving is least urgent.
0:15:55 > 0:16:02If the calf is lucky, it may be allowed to spend a day or two in a scrape on the ground before moving.
0:16:02 > 0:16:08But it may have to be up and running within hours.
0:16:12 > 0:16:17A severe winter can decimate a herd,
0:16:17 > 0:16:22but saiga can recover their numbers with extraordinary speed.
0:16:22 > 0:16:30A female calf, born in the spring, can mate in the autumn and bear her first single baby the next spring.
0:16:30 > 0:16:33The next year, when she is adult,
0:16:33 > 0:16:36she usually produces twins.
0:16:36 > 0:16:44So a herd that has been almost wiped out can be 100,000 strong again within a few years.
0:16:44 > 0:16:52The steppe eagle is hardly big enough to take a young, vigorous saiga calf.
0:16:52 > 0:16:55It's mostly a carrion feeder.
0:16:55 > 0:16:59But if the baby saiga weakens,
0:16:59 > 0:17:02the eagle will finish it off.
0:17:05 > 0:17:10As the days warm, the herd moves north,
0:17:10 > 0:17:15following the retreating snow and feeding on the new grass.
0:17:28 > 0:17:33But within a few months the cold begins to return
0:17:33 > 0:17:36and the herd treks back again.
0:17:36 > 0:17:44By the time the young saiga is a year old, it may have walked as much as 4,000 miles.
0:17:45 > 0:17:48Baby scorpions get a lift.
0:17:48 > 0:17:52Their mother wanders over a wide range,
0:17:52 > 0:17:55as most hunters must do.
0:17:55 > 0:18:00As soon as they hatch, they clamber up on to the mother's back.
0:18:00 > 0:18:04There is no safer place for them
0:18:04 > 0:18:10than beneath the formidable sting on the end of her tail.
0:18:17 > 0:18:20A mother shrew parks her babies,
0:18:20 > 0:18:23hiding them in a safe place,
0:18:23 > 0:18:26often under a stone.
0:18:26 > 0:18:29Having herself fed on insects,
0:18:29 > 0:18:32she returns to feed them on milk.
0:18:32 > 0:18:37But if she suspects her chosen nursery has become unsafe,
0:18:37 > 0:18:45she gives her young, whose eyesight is not very good, a command with an ultra-sonic squeak.
0:18:45 > 0:18:47They obey immediately.
0:18:59 > 0:19:06Among eider duck, looking after the young is a job for females, not the black and white males.
0:19:06 > 0:19:09But the females share the load.
0:19:09 > 0:19:14Mothers lead their newly-hatched ducklings down to the sea.
0:19:14 > 0:19:23There, other females - aunties - take charge of them, allowing the mothers to go for a good meal.
0:19:23 > 0:19:31These aunties are young females who haven't paired this season and who have no young of their own.
0:19:31 > 0:19:36More and more families come down to the water,
0:19:36 > 0:19:42until the creche may have as many as 500 ducklings in it.
0:19:49 > 0:19:57The young ducklings are able to feed themselves, but they are completely defenceless.
0:19:57 > 0:20:02And once again, there are enemies around.
0:20:13 > 0:20:18The gull assesses the defences of the creche,
0:20:18 > 0:20:24and finds that aunties can be just as brave as any parent.
0:21:02 > 0:21:10Even though the gull is driven off and gets nothing, there are inevitably casualties.
0:21:18 > 0:21:23This is a mara, a Patagonian relative of the guinea pig,
0:21:23 > 0:21:26and it, too, uses a creche.
0:21:26 > 0:21:31A dozen or so females give birth to their babies in the same place,
0:21:31 > 0:21:36so there may be as many as 40 young maras in one nursery hole.
0:21:36 > 0:21:43There are nearly always one or two parents around,
0:21:43 > 0:21:48for mammals can't abandon their babies for days, as eider ducks do.
0:21:48 > 0:21:52Each mother has to return every day
0:21:52 > 0:21:55to give her babies milk.
0:21:55 > 0:21:57She aims to feed only HER babies -
0:21:57 > 0:22:02usually twins - who she recognises largely by their smell.
0:22:02 > 0:22:10But that doesn't stop the others in the nursery from trying their luck.
0:22:49 > 0:22:54Sometimes the whole creche pester a mother so vigorously
0:22:54 > 0:23:00that she may just give up and let all of them take her milk.
0:23:35 > 0:23:39Some bats also use a creche system.
0:23:39 > 0:23:42All these are females -
0:23:42 > 0:23:49free-tailed bats that flew up to this cave in Texas from Mexico a few weeks ago,
0:23:49 > 0:23:53leaving their mates to their own devices.
0:23:53 > 0:23:57The cave's a perfect maternity ward.
0:23:57 > 0:24:04It's warm and dry, and the surrounding countryside is rich in insects to feed on.
0:24:04 > 0:24:13A million mothers chose this cave, and now there are a million new-born babes here as well.
0:24:13 > 0:24:18In the late afternoon, the mothers leave to feed.
0:24:26 > 0:24:32The departure starts before it is properly dark,
0:24:32 > 0:24:35for it takes a long time
0:24:35 > 0:24:41for a million bats to stream out of the relatively small cave mouth.
0:25:07 > 0:25:13The babies they leave behind are massed in one huge creche.
0:25:13 > 0:25:18They cluster together in order to keep warm.
0:25:18 > 0:25:26Even now, when they are just beginning to grow their fur, staying together saves energy.
0:25:26 > 0:25:31But imagine trying to find your baby among this lot!
0:25:31 > 0:25:38Throughout the night, mothers visit the creche to give their babies a feed of milk.
0:25:38 > 0:25:42LOUD FLUTTERING OF WINGS
0:25:42 > 0:25:50This mother knows the cave layout well enough to land quite close to where she last left her baby.
0:25:50 > 0:25:55But a lot of jostling goes on, so the baby may have moved a little.
0:25:55 > 0:26:03As she searches, the other hungry youngsters struggle to reach the nipples in her armpits.
0:26:28 > 0:26:31No luck. She gives up.
0:26:31 > 0:26:37If a baby isn't fed at least once a night, it's likely to die.
0:26:37 > 0:26:41So she returns and starts again.
0:26:48 > 0:26:53On the edge of the creche, a baby waits for its mother,
0:26:53 > 0:26:58who clearly hasn't returned for some time.
0:26:58 > 0:27:03Below, scavengers wait for corpses that might fall.
0:27:09 > 0:27:17The mother's main way of finding the baby is, astonishingly, by recognising its cry,
0:27:17 > 0:27:21even in this pandemonium.
0:27:35 > 0:27:40At last! This is her baby, and at last it feeds.
0:27:51 > 0:27:59Vast nurseries like this can only exist if there is an abundance of food around.
0:27:59 > 0:28:04Not far from Texas, in Florida, the situation is very different.
0:28:04 > 0:28:10The white sand on which these scrubby pines grow
0:28:10 > 0:28:18is so poor in nutrients that there is little to sustain adult animals, let alone their babies.
0:28:18 > 0:28:23Even birds find it a hard place in which to live.
0:28:23 > 0:28:28Food is hard to find and there aren't many places to build a nest,
0:28:28 > 0:28:35but it's home to a bird that's been studied almost as intensively as any bird in the world.
0:28:35 > 0:28:40And this is it - the Florida scrub jay.
0:28:40 > 0:28:48Because every jay in this area has been banded for almost 20 years, we know who each one is.
0:28:48 > 0:28:57This one, with three rings on her right leg, is a young female from the territory to the left.
0:28:57 > 0:29:02This one, with bands on both legs, is the dominant male...
0:29:02 > 0:29:05HE LAUGHS
0:29:05 > 0:29:08..who has a nest in this territory.
0:29:12 > 0:29:21Food is so scarce that more than two adults need to search for it if the chicks are to be fed.
0:29:21 > 0:29:24This bird is not the parent of these nestlings.
0:29:24 > 0:29:29It's one of last year's chicks, who stayed on to help raise this brood.
0:29:29 > 0:29:38Young female helpers, after a year or two, usually leave to look for territories of their own.
0:29:38 > 0:29:42But males may stay for up to seven years.
0:29:42 > 0:29:48One may inherit the nesting site when the old breeding male dies,
0:29:48 > 0:29:51but most will never father a brood.
0:29:51 > 0:29:54They find their reproductive reward
0:29:54 > 0:29:59in helping to raise their younger brothers and sisters.
0:30:13 > 0:30:20Guarding the food supply is just as important as collecting it,
0:30:20 > 0:30:27and some of the young helpers act as sentinels, keeping an eye out for thieves.
0:30:29 > 0:30:37This trespasser from a neighbouring territory sneaks in to try to steal food.
0:30:37 > 0:30:40That can't be allowed.
0:30:43 > 0:30:46SCREECHING
0:31:05 > 0:31:09Back to normal duties.
0:31:09 > 0:31:14Another hungry intruder, an indigo snake.
0:31:14 > 0:31:19The meal it is searching for could well be a jay chick.
0:32:05 > 0:32:08So teamwork saves the nest.
0:32:08 > 0:32:12As a result of studies here, we now know
0:32:12 > 0:32:20that pairs with teams to help them are much more successful in rearing their young.
0:32:20 > 0:32:25And such co-operation is quite widespread among birds.
0:32:25 > 0:32:32Some species of woodpeckers and wrens use this form of co-operation, as, indeed, do some mammals.
0:32:32 > 0:32:38Elephants, for example, collaborate to bring up their babies.
0:32:38 > 0:32:41At least, the females do.
0:32:41 > 0:32:48Adult males wander off and live more or less solitary lives away from the herd.
0:32:50 > 0:32:55A new baby is the focus of great interest and affection,
0:32:55 > 0:33:00not only from its mother, but from elder sisters, aunts,
0:33:00 > 0:33:08and especially the old lady who leads the herd and who is almost certainly its grandmother.
0:33:28 > 0:33:33Sometimes, indeed, everyone wants the privilege of being nanny.
0:34:03 > 0:34:09This visiting bull is not used to infants.
0:34:11 > 0:34:16Great consternation among sisters and aunts.
0:34:28 > 0:34:34Childhood, of course, is a time for play,
0:34:34 > 0:34:41and play is a way of finding out about your world and acquiring the skills you need in later life.
0:35:06 > 0:35:12Playing in water is fun not only for infants but for adults.
0:35:12 > 0:35:19It's a pleasure that elephants never seem to lose, no matter how old they are.
0:35:21 > 0:35:26Still, it takes a bit of getting used to.
0:35:46 > 0:35:51And how do you get your legs clean afterwards?
0:36:12 > 0:36:17Elephants have a very long childhood.
0:36:17 > 0:36:24It varies a lot, but most don't reach the age of puberty till they're 11 or 12 years old.
0:36:24 > 0:36:32As they approach that time, they begin to try out some of the things that adults do.
0:37:09 > 0:37:14An elephant doesn't need to be a fast learner.
0:37:14 > 0:37:19It's a strict vegetarian, and its range of food is small.
0:37:19 > 0:37:27It doesn't have to worry unduly about enemies - its great bulk is a protection in itself.
0:37:27 > 0:37:34But if you live for 60 or 70 years, then there is no hurry to grow up and assume adult responsibilities.
0:37:34 > 0:37:41It takes time to build a body that will eventually weigh five tons.
0:37:41 > 0:37:46Chimpanzee childhood is more complicated.
0:37:46 > 0:37:52Chimp youngsters must know what is good to eat and what isn't.
0:37:52 > 0:37:55They have a complex social life,
0:37:55 > 0:38:02so a young chimp must learn how to behave towards different individuals in the community.
0:38:02 > 0:38:07And all kinds of physical skills have to be acquired.
0:38:07 > 0:38:13Babies spend their first few months clinging to their mother,
0:38:13 > 0:38:18and from this privileged and protected position
0:38:18 > 0:38:23they have a grandstand view of how things are done.
0:38:23 > 0:38:29These Ivory Coast chimps have a special skill all of their own.
0:38:29 > 0:38:32They've learned how to crack nuts.
0:38:32 > 0:38:40But when you're only nine months old, watching mother crack nuts loses its fascination after a bit.
0:38:40 > 0:38:46The shells, on the other hand, have possibilities as toys.
0:39:07 > 0:39:10ANGRY SCREECHING
0:39:10 > 0:39:18You also have to learn quickly which adults are likely to be your friend
0:39:18 > 0:39:23and who it might be safer to steer clear of.
0:39:30 > 0:39:37This slightly older infant is beginning to follow the big boys and copy the way they behave,
0:39:37 > 0:39:43so discovering what life is like among the grown-ups.
0:39:51 > 0:39:56And mother is always there to provide comfort and protection
0:39:56 > 0:40:01when things get a bit baffling and worrisome.
0:40:26 > 0:40:29Nut-cracking is complicated,
0:40:29 > 0:40:37involving some of the most advanced tool-using techniques practised by any animal.
0:40:37 > 0:40:42It's no use just bashing a stick on the ground.
0:40:42 > 0:40:45You have to have a decent anvil.
0:41:03 > 0:41:11Nuts have to be collected and then carried to the place where they can be cracked.
0:41:28 > 0:41:34The anvil is almost always the root of a tree.
0:42:27 > 0:42:33Eventually the time comes when, at last, you get the hang of it.
0:42:35 > 0:42:42For chimpanzees, acquiring adult skills is a gradual process.
0:42:42 > 0:42:47But that is not the case for most animals.
0:42:47 > 0:42:54For these youngsters - baby albatross on the Pacific Leeward Islands,
0:42:54 > 0:42:59the ending of childhood is brutally abrupt.
0:42:59 > 0:43:03Within the next few days, they must fly
0:43:03 > 0:43:11and almost immediately become as accomplished in the air as their parents.
0:43:12 > 0:43:17The best they can do by way of preparation
0:43:17 > 0:43:24is to strengthen their breast muscles by beating their wings.
0:43:29 > 0:43:34If they don't get it right first time, it could be catastrophic.
0:43:34 > 0:43:37Dark shapes appear in the shallows.
0:44:22 > 0:44:27Tiger sharks. Every year, at this precise time,
0:44:27 > 0:44:30they appear from nowhere.
0:46:08 > 0:46:15For the bats in Texas, too, childhood is coming to an end.
0:46:15 > 0:46:18The babies are now a month old.
0:46:18 > 0:46:25The time is coming for the mothers to fly back to the males in Mexico,
0:46:25 > 0:46:28taking their babies with them.
0:46:30 > 0:46:38For the past few days, many of the babies have been going on short practice flights within the cave.
0:46:38 > 0:46:45But now some of them are accompanying the adult females as they fly out into the open sky.
0:46:45 > 0:46:48But they're far from expert fliers.
0:46:48 > 0:46:54Here's one that has crash-landed within a few yards of the cave.
0:46:54 > 0:47:01In the cave, he was very safe - about one in a hundred babies die in there.
0:47:01 > 0:47:06But out here he is surrounded by danger.
0:47:06 > 0:47:13Of the million bats born in there, three-quarters will be dead before they are adult.
0:47:13 > 0:47:19His trials of life really are just starting. Good luck to you.
0:48:24 > 0:48:27Subtitles by BBC - 1990