{1229}{1326}Out of the darkness emerges|a 12 tonne giant.
{1323}{1441}She is a an Indricothere and|she is about to give birth.
{1460}{1556}She seeks out a secIuded spot|in a canyon where she hopes the new
{1545}{1622}born wiII be safe from predators.
{1675}{1803}It is now just before dawn and|at Iast her two year pregnancy
{1786}{1846}is coming to an end.
{2073}{2175}The caIf is a maIe and|he is aIready in troubIe.
{2305}{2381}The noise and smeII of|the mother's Iabour has attracted
{2374}{2448}the predators -Hyaenodon.
{2460}{2552}Despite the name, these are not|reIatives of hyenas.
{2544}{2618}These are more dangerous by f ar.
{2616}{2717}Next to the Indricothere they may Iook|smaII but these carnivores are
{2703}{2834}as big as rhinos and they are|easiIy capabIe of kiIIing the caIf,
{2818}{2883}if they can get past his mother.
{2934}{3035}As the predators circIe she desperateIy|tries to keep the baby between her
{3023}{3120}Iegs where she can defend him|with powerfuI kicks.
{3320}{3402}But the Hyaenodon keep|coming and coming.
{3460}{3577}This caIf wiII be Iucky to see|his first sunrise.
{3980}{4049}It is a time caIIed the OgIiocene.
{4046}{4163}The worId has just been through years|of catastrophic cIimate change that
{4148}{4236}Ied to the extinction of|one species in five.
{4239}{4333}Earth has since bounced back but|in the process it's become
{4322}{4484}a changed worId - different weather|different pIants and different animaIs.
{4556}{4647}Here in MongoIia some animaIs|have grown enormous.
{4674}{4774}This programme wiII foIIow the f ate of|just one of these giants,
{4762}{4819}a baby Indricothere.
{4820}{4919}During the night this canyon was|the scene of his dramatic birth
{4907}{4992}but it seems his mother|saw off the Hyaenodon.
{4981}{5044}He is a very Iucky caIf.
{5059}{5151}As a new born he aIready weighs|a quarter of a tonne.
{5170}{5267}And his Iegs aren't used to bearing|any weight at aII so he'II spend
{5256}{5341}the rest of the morning|Iearning how to waIk.
{5450}{5562}Around him, the other residents of|the canyon are starting to stir.
{5552}{5635}Strange beasts Iike the ChaIicotheres.
{5631}{5720}AImost three metres taII they waIk|on their knuckIes to protect
{5710}{5767}their Iong cIaws.
{5764}{5866}These powerfuI Iimbs are very effective|defensive weapons.
{5854}{5975}But more often these herbivores use|them to hook down branches to get at the
{5959}{6006}softest Ieaves
{6112}{6238}They waIk Iike goriIIas and|eat Iike pandas but their cIosest modern
{6221}{6303}reIatives are actuaIIy horses.
{6438}{6529}The new born caIf aIso has|food on his mind.
{6528}{6625}This is the beginning of the|most vuInerabIe period of his Iife.
{6617}{6715}He'II be totaIIy dependent on his mother|for at Ieast three years.
{6708}{6769}He needs her protection|and for the first
{6763}{6833}year he aIso reIies on her miIk.
{6826}{6928}This is an astonishingIy Iong|commitment for any mother.
{6915}{7031}But if he can just survive that Iong|his size wiII mean there wiII
{7016}{7103}not be a predator on earth|that can touch him.
{7200}{7323}In the OIigocene Iarge parts of|the worId have become highIy seasonaI.
{7307}{7421}Here in MongoIia Iong, dry seasons|are broken by short, vioIent,
{7407}{7448}wet seasons.
{7447}{7571}The cIimate has shaped not onIy|the environment but aIso the animaIs.
{7622}{7691}It is survivaI of the meanest.
{7701}{7829}And they don't come much meaner than|this - a giant EnteIodont,
{7813}{7872}the buIIy of the pIains.
{7875}{8014}These are distant reIatives of the pig,|two metres taII, aggressive
{7996}{8169}and buiIt Iike tanks but with a|brain no bigger than an orange.
{8172}{8277}The bear dog mother and cubs retreat|to a safer distance but
{8264}{8320}it isn't going to be their day.
{8316}{8397}AIthough these reIatives of both|bears and dogs are vicious
{8388}{8511}IittIe predators, at the water hoIe|it's size that matters.
{8574}{8654}The mother Indricothere has aIso|come here to drink but
{8645}{8714}her caIf is nowhere to be seen.
{8825}{8918}A second maIe EnteIodont arrives|at the water hoIe.
{8906}{8978}During the mating season|these huge scavengers get very
{8971}{9103}aggressive towards each other as|they try to estabIish who is top hog.
{9107}{9199}EnteIodonts are their own worst enemy.
{9298}{9398}It is enough to put off|even an Indricothere.
{10179}{10310}The EnteIodont's fearsome set of|teeth have infIicted deep wounds
{10294}{10343}on the Ioser
{10489}{10583}Back in the canyon,|the caIf Iies motionIess.
{10580}{10696}He is pIaying dead.|UntiI disturbed that is.
{11003}{11081}This is the young caIf's|survivaI strategy.
{11073}{11153}In his mother's absence|he instinctiveIy Iies stiII
{11143}{11217}to avoid the attentions of predators.
{11271}{11396}OnIy when she eventuaIIy returns does|he come out of hiding.
{11605}{11702}He remains within the comparative|safety of the canyon waIIs for
{11691}{11734}another week.
{11732}{11825}But then his mother decides|it is time to Ieave.
{11978}{12067}The caIf is now strong and|sure-footed enough to venture
{12058}{12209}out onto the open pIains where|he wiII spend the rest of his Iife.
{12421}{12536}Not since the dinosaurs has|nature got this big.
{12588}{12693}Indricotheres are reIated to rhinos|but their size is
{12681}{12729}in a different Ieague.
{12724}{12828}A fuIIy grown maIe stands over|seven metres taII and weighs
{12814}{12868}in at 15 tonnes.
{12866}{12958}That's equivaIent to|eight modern rhinos.
{12953}{13050}No other Iand animaI even comes cIose.
{13156}{13259}Being big not onIy protects them from|predators but in this dry
{13246}{13371}Iand aIIows them to go without|food or water for days.
{13475}{13578}The caIf is eager to expIore this big|new worId.
{13583}{13661}But his first encounter|is a shock for him.
{13678}{13785}An aggressive bear dog has no time|for his curiosity.
{13773}{13832}Her cubs are nearby.
{13847}{13939}And to her, the gawky caIf is a threat.
{14024}{14120}It doesn't take much to send him running|back to his mother.
{14358}{14445}Right from the beginning,|the caIf starts copying his mother
{14435}{14507}to Iearn how to deaI with the worId.
{14498}{14635}So when she arrives in her usuaI|feeding area and sniffs a piIe of dung
{14617}{14670}he does the same.
{14671}{14800}One day he wiII understand that since|every Indricothere has a unique odour
{14783}{14903}this is how his mother teIIs which|other animaIs are in the area.
{14886}{14964}His Iessons in survivaI have begun.
{15077}{15208}Nearby is a juveniIe Indricothere|just over three years oId.
{15251}{15351}This is not stranger but his mother's|previous caIf.
{15345}{15470}However she has no time for him now and|vioIentIy repeIs him.
{15466}{15589}He doesn't know it but our caIf is|Iooking at his own future.
{15865}{15930}The Iong, dry season is just starting.
{15924}{15999}But there is stiII pIenty of food around.
{15991}{16080}In another month or so the situation|wiII be very different.
{16071}{16180}And so animaIs are gorging themseIves|whiIe the going is good.
{16233}{16357}As the mother browses she has the tops|of the trees to herseIf.
{16344}{16425}It's another advantage of being big.
{16530}{16618}OnIy two months oId,|the caIf doesn't need to eat.
{16608}{16679}He is stiII Iiving off his mother's miIk.
{16671}{16757}But it doesn't stop him|trying to imitate her.
{16748}{16846}This is how caIves Iearn which|pIants are safe to eat.
{16936}{17036}However, this is a bad time for him|to wander off on his own.
{17027}{17132}Just 20 metres away a|Hyaenodon is staIking.
{17801}{17934}Hyaenodon's jaws have a bone-shattering|force of over 1000Ibs per
{17917}{17947}square inch.
{17947}{18034}One bits breaks the ChaIicothere's neck.
{18174}{18308}They are capabIe of eating|everything on a carcass.
{18455}{18521}But today he isn't going to|get the chance.
{18514}{18616}The IocaI buIIies have arrived|and he is outnumbered.
{18922}{19032}In a futiIe attempt to hide the|smeII of the carcass the Hyaenodon
{19018}{19063}defecates on it.
{19068}{19162}But it wiII take more than|that to put off the EnteIodonts.
{19802}{19897}The hogs from heII have won the prize.
{20165}{20259}The dry season has|transformed the Iandscape.
{20254}{20346}It's as if the whoIe Iife bIood|has drained out of the pIains.
{20345}{20418}This is what it means to be|a seasonaI worId -
{20415}{20525}it hasn't rained for months,|there is no greenery Ieft to eat and
{20512}{20580}there is precious IittIe to drink.
{20576}{20661}Here in MongoIia, mammaIs have evoIved|to cope with even
{20651}{20706}these kindsof conditions.
{20701}{20818}But at this time of year they are|put under their greatest stress.
{21044}{21155}The mother Indricothere has not|found water for severaI days.
{21142}{21243}And in her dehydrated state she|is not producing miIk.
{21231}{21395}The caIf is now nine months oId and|it is his first taste of true hardship.
{21632}{21777}Despite his repeated attempts to suckIe,|the mother rejects him.
{21938}{22046}Because of their size, aduIts can|survive without water for days.
{22034}{22141}But the caIf, being smaIIer|has fewer reserves to draw on and
{22129}{22201}is getting dangerousIy weak.
{22602}{22722}The nights are cooIer and a f ar|better time for them to move around.
{22708}{22802}So every evening they set off|in search of water.
{22823}{22894}Other Indricotheres are|on the same journey.
{22888}{23002}And tonight, the pair is joined|by an oIder femaIe.
{23011}{23118}Indricotheres can easiIy Iive|nto their 80s and this Iongevity
{23105}{23200}gives them a unique knowIedge|of their environment.
{23284}{23412}If there is any water nearby,|it's a good bet the oId femaIe
{23395}{23447}knows where it is.
{23698}{23838}At Iast they find the muddy remnant|of a Iake and just in time
{23823}{23907}because the caIf is cIose to coIIapse
{23901}{24047}He wiII have to wait a whiIe for|his miIk but at Ieast
{24277}{24398}It is the first night for some time|that these giants can Iie down
{24382}{24425}and get a proper sIeep.
{24753}{24853}The next morning the mother receives|an earIy caII.
{24848}{24916}The caIf is stiII starving.
{24916}{25052}But this time she responds and|he is rewarded with miIk.
{25398}{25517}When the rains eventuaIIy come,|they come down hard.
{25612}{25739}From parched pIains to a|sIippery quagmire,
{25721}{25834}everything changes in aninstant.
{26262}{26360}But the sudden downpours|bring disaster for some.
{26352}{26504}This bear dog's den has been undermined|by the fIood waters and coIIapsed.
{26489}{26588}An anxious mother is forced|to dig to find her cubs.
{26756}{26873}She finds onIy one,|and it's aIready dead.
{26962}{27080}There is a river now where|none existed before.
{27076}{27179}In their search for food|the pair must cross it.
{27261}{27403}This is a whoIe new ordeaI for the caIf|and at first he is very reIuctant to
{27383}{27450}foIIow his mum into the water.
{27689}{27800}In the end though, it is obvious|that he is more frightened of being
{27786}{27859}Ieft behind than he is of|crossing the river.
{27967}{28050}This is the first swim of his Iife.
{28101}{28211}UnfortunateIy, it turns|out to be the easy bit.
{28682}{28777}When the caIf gets to the other side|he stiII has to get to the top of
{28766}{28814}the opposite bank.
{28810}{28910}It is steep and sIippery and,|unIike his mum, he isn't going
{28897}{28961}to make it in one smaII step.
{28972}{29063}There is nothing his mother|can do to heIp him.
{29138}{29262}He is on his own and he doesn't Iike it.
{30063}{30186}Not an easy task for such a heavy baby.
{30380}{30477}The drought might have been a tough time|but in many ways the coming
{30465}{30570}of the rains marks the end of|the good Iife for the caIf.
{30570}{30663}It is time for him to feed himseIf.
{30653}{30761}Indricothere caIves are weaned|off miIk at about a year oId.
{30752}{30842}But having known IittIe eIse but miIk|for his whoIe Iife,
{30832}{30915}he needs quite a Iot of|persuading to give it up.
{30988}{31059}Try as he might to get some of|his f avourite tippIe,
{31052}{31114}mum is having none of it.
{31110}{31203}He wiII have to eat his greens|or go without.
{31432}{31563}After the Iong, dry season,|coIour sIowIy returns to the pIains
{31546}{31626}as the cycIe of Iife starts over again.
{31648}{31767}And for the Indricotheres|it is time for mating.
{31833}{31926}A young maIe has caught the scent|of a receptive femaIe.
{31954}{32064}It is the caIf's mother who is fertiIe|again now she has stopped
{32049}{32109}suckIing her caIf.
{32174}{32292}The caIf pIainIy has no idea what|to make of this approaching coIossus.
{32277}{32370}And at this point his mother show|no interest either.
{32453}{32552}Then a second, oIder maIe|appears on the scene.
{32552}{32674}He emphasises his status by spraying|the ground IiberaIIy with urine.
{32827}{32943}The younger maIe isn't so easiIy|intimidated and the two rivaIs size
{32929}{33033}each other up before starting|a brutaI contest.
{33266}{33342}When 30 tonnes worth of|Indricothere fight,
{33333}{33422}the forces invoIved are bone-shattering.
{33417}{33532}The skuIIs of maIes are speciaIIy|buiIt to withstand these contests.
{33715}{33850}It takes haIf an hour of abuse before|the oIder maIe backs down.
{34000}{34116}But with the fight over,|the caIf is now at serious risk.
{34101}{34213}The biggest threat to a young|Indricothere is an aduIt maIe.
{34206}{34307}During mating, caIves can get|trampIed to death.
{34558}{34662}It is the first time that another|individuaI has come between him
{34649}{34671}and his mother.
{34673}{34770}In his distress he tries desperateIy|to get in the way,
{34759}{34812}to stop the mating.
{35136}{35267}Over the next 36 hours the maIe wiII|mate with the caIf's mother
{35248}{35324}severaI more times, preventing any|other maIes from doing so.
{35322}{35401}Our caIf is in for a tough time.
{35907}{35997}It's the very beginning of the|wet season and the ChaIicotheres
{35987}{36063}have started to search out new growth.
{36199}{36264}The mother Indricothere is expecting.
{36266}{36348}She is in f act onIy days|from giving birth.
{36398}{36518}Standing by her is the caIf,|now three years oId and weighing
{36501}{36546}over a tonne.
{36544}{36620}He's obviousIy Iearnt many of the tricks|of Indricothere Iife from
{36611}{36747}his mother - Iike using trees to|scratch the parasites off his back.
{36801}{36938}However, nothing he has Iearnt so f ar|wiII prepare him for what
{36918}{36970}is about to happen.
{36967}{37106}In the morning the caIf wiII suffer|the biggest upset of his Iife.
{37444}{37552}The mother is behaving very oddIy|indeed towards her caIf.
{37591}{37662}But she is onIy doing what|she has to do.
{37700}{37761}She is chasing him away.
{37833}{37925}To give her unborn caIf|the best chance in Iife,
{37916}{38046}she must sever the three year oId bond|she has had with the maIe caIf.
{38126}{38218}It is time for him to make his own way|in the worId.
{38230}{38294}This is the hardest Iesson of aII.
{38853}{39004}For some time the caIf disappears|onIy to turn up a coupIe of weeks
{38984}{39096}Iater aIone on a river bank.
{39140}{39253}The cause of his Iimp is uncIear|but the most IikeIy expIanation
{39239}{39341}is that he has had a run in with|a young aduIt Indricothere,
{39328}{39398}one of the few creaturesthat|can threaten him.
{39390}{39511}And now he is heading back to|the onIy safety he knows.
{39622}{39712}His mother has a new caIf|in tow and her maternaI instincts
{39702}{39782}have been transferred to the new born.
{39897}{39977}To her, he is now just a threat.
{40258}{40346}He is never again going to have|the protection of his mother.
{40339}{40435}The rest of his Iife|he wiII spend aIone.
{40617}{40770}One month, two months, three months|go by and there is no sign
{40749}{40796}of the caIf.
{40803}{40947}Then suddenIy, one day he reappears,|back in his oId territory.
{40932}{41032}His injury has heaIed and|he seems in good heaIth.
{41094}{41183}But he is dangerousIy|cIose to an EnteIodont.
{41502}{41623}Any fears about his safety suddenIy|seem to be mispIaced because
{41608}{41751}this indricothere is now big enough|to Iook after himseIf.
{42204}{42296}Next episode prepare to come|f ace to f ace with mankind's
{42286}{42323}beginnings .
{42321}{42410}when we go back to Africa|three miIIion years ago to meet
{42398}{42475}a species of ape that waIked upright.
{42475}{42567}Our ancestors Iived in a dangerous worId.
{42558}{42680}UnIike us, they weren't predators,|they were prey.