I'll planet Earth one creature embodies all that is amazing about Survivor he has adapted to wildly varying habitats and evolved weapons unique to the animal kingdom its greatest asset a bone-crushing bite this mystical creature has overcome extreme climate change ferocious rivals and the deadliest threat of all to emerge as one of evolutions ultimate survivors [Music] [Music] 45,000 years ago North America [Music] vast grasslands dominate the landscape [Music] this is one of the most feared carnivals on planet Earth the giant short-faced bear weighs as much as a small car for decades scientists believe that this was the ultimate predator the earliest paleontologist thought this would mean an incredible runner this was a an animal well adapted for high speeds with long strides that could go really fast and chase down bison or mammoths and be an incredible super predator but the biggest bear that ever lived died out and yet smaller bears its relatives not only thrive colonize the Platte [Music] um skin match modern bears for versatility they survive on meat on vegetation they can even survive on insects they live in wildly different habitats from the steaming subtropical forests of India to the icy wastes of the Arctic paleontologists discovered that during man's quest to master nature bears proved a formidable opponent [Applause] [Music] yet the most formidable of all died out what skills have other bears evolved to survive the secrets of beer evolution lie buried in the earth itself [Music] paleontologists are time travelers they visit our ancient past by digging down into the Earth's surface each layer of rock is like a time-lapse recording major events in the planets history - eruptions natural disasters [Music] and climate change it's all recorded in sediment planet Earth's T&A the mystery of bear evolution starts 20 million years ago in Central Europe [Music] planet earth is hotter than today and covered with forests man's rise is still many millions of years away this is the first true bed the dawn bear is the size of a fox terrier dog he comes from a long line of dedicated carnivores from home however on the ground life is dangerous he struggles to compete with dogs hyenas and cats forcing him to take refuge in the treetops but finding a steady source of meat up here poses a new challenge scientists are researching the genetic x-factor their transformed a small doglike creature into the Bears we know today [Music] dr. Anjali Goswami of the University of Cambridge is an expert in mammal evolution [Music] by comparing skull of a modern bear to another typical carnivore like a big cat she reveals the secret gift the father of all bears passed on to its descendants well if you look at really a more standard carnivore something like a tiger you'll find that they have these really laid like upper premolar and that occludes with this really blade like lower molar and that creates a shearing action that's really well evolved for slicing meat ABARES although they've descended from these carnivorous ancestors I've actually done something quite different so when you look at a bear skull you can see that they've taken this premolar and instead of having it blade like it's instead more triangular so they have a vintage that's very well evolved for grinding having the ability to slice meat with these four national teeth and having these really broad molars gives them a lot of evolutionary flexibility [Music] because bears have slicing and grinding teeth they can eat meat and vegetation critical for the dawn bear these teeth allow it to feed high up in the trees safe from the ground predators dental flexibility is the crucial gift that the dawn bear passes on to all of its descendants over the next six million years planet Earth Basques in warm temperatures [Music] but then the climate changes dramatically and so do the fortunes of the early bear temperatures dim sharply 14 million years ago colder weather strips away subtropical forests oh the tree-dwelling dawn bear must somehow adapt to this almost treeless grass-covered world fossil records revealed at 14 million years ago two descendants of the darn bear had spread all over the world the ancestor of the giant panda and a bear that would eventually become the giant short-faced bear [Music] the short-faced bear looks like a bulldog with its forest habitat vanishing it takes to the ground in search of food [Music] but the fossil records also present a mystery to be solved they show that 14 million years ago the lesser short-faced bear lives in North America [Music] today a 56 mile waterway known as the Bering Sea separates Eurasia from North America [Music] how did the ancestors of the short-faced bear make this incredible journey to the new world the answer to the mystery lies further north in the Arctic the cold stop 14 million years ago causes water in the polar regions to freeze ice has a profound effect on planet Earth water that normally flows down into the oceans remains frozen at both poles this triggers a dramatic fall in global sea levels suddenly land emerges out of seeds terrain appears between what is today Alaska and eastern Siberia Nonna's Beringia or the bering land bridge it stretches 1,000 miles from north to south and connects Asia to North America Beringia or the bering land bridge served as a corridor for the exchange of plants and mammals and eventually people between the old and the new world yan sisters the bears probably came from asia crossed the Bering Land Bridge moved into North America and then bear evolution took place here fourteen million years before man makes the same epic journey early bears take this bridge to the new world however over thousands of years temperatures rise again the polar ice melts the Seas reclaim Beringia the short-faced bear is trapped in the new world where the cold has also destroyed large areas of woodland [Music] the shrinking wooded habitats of the lesser short-faced bear they see that there's all this ripe fresh meat out on the open plains either does it evolve and go after that fresh meat or does it hang out in the shrinking forest and perish the short-faced bear must adapt to hunt on the plains [Music] or face extinction [Music] about 2.5 million years ago one of the most cataclysmic climatic events ever strikes planet Earth and dramatically alters the course of their evolution a cold current has isolated Antarctica from the influence of warm currents then South America the next to North America this isolates the Atlantic Ocean from the Pacific Ocean now the Arctic develops permanent ice the planets temperature drops shot the ice age spells doom for hundreds of species it wipes out the saber-tooth Tiger woolly mammoths and the grounds only the toughest most adaptable will survive bears evolved some of the natural world's most ingenious tools but not all the bear species will make it through the ancestral dawn there from 20 million years ago has now given rise to at least three separate species the short-faced bear is trapped in north america the ancestor of black and brown bears emerges in Eurasia where the ancient panda makes an extraordinary transformation to survive the cold at first the panda turns black and white scientists believed to act as camouflage against snow in rock [Music] when it's meat supply vanishes the Panda evolves a simple but ingenious solution to hunger two million years ago in China he finds a potential food source bamboo there's lots of it but the pandas are carnival there's another drawback it literally can't handle this tough chewy crop the carnivores paws are designed for hunting animals not for breaking off vegetation one hunger is often a major driving force in evolution the Panda has five claws but they can't grip a thin bamboo shoot' to counter this evolution exploits a bone below the claws it grows into a bump that acts as an opposable force to the five claws it's known as the pandas thumb which allows the bear to grip and snap stalks of bamboo now the Bears crushing jaw in grinding teeth play therefore pandas have to really break up the bamboo as much as possible before they digest it in order to withdraw as many nutrients as possible so having this very very strong bite force and this really strong grinding dentition allows them to do that and subsist on this otherwise very nutrient poor diet the Panda solves its food crisis now elsewhere in Asia another group of ancient bears must do the same huge glaciers spread through the Himalayan mountain range driving a group of bears into the temperate forests of India here the carnivores struggled to eke out a living wolves and hyenas beat them - the available meat [Music] to survive these bears evolved a bizarre an amazing set of tools two million years ago in the temperate forests of India a group of starving bear stumbles across an unusual but untapped source of food [Music] to exploit it the species relies on its ancient gift an adaptable mouth and teeth it develops a long time a larger stout and loses its first mayor of incisor teeth thereby sacrificing the Bears trademark bite it becomes a new species the sloth bed its evolved this unusual oral toolset to target a particular source of food the sloth bear has found a different source of food that that actually does maintain steady supply throughout all the different seasons let's ants and termites it has a very strong claws that uses to actually break the top of the termite mound and by using its very mobile nose it can actually create a suction across the top of the termite man closes nostrils and almost a vacuum out the termites from the mound the sloth bear like the Panda adopts an extraordinary strategy to survive the Ice Age two million years ago in the middle of the Ice Age another bear has adapted to the cold by becoming massive we know this because of a spectacular fossil father in a river in the Yukon region of Canada gold prospector finds an enormous skull [Music] it looks like the skull of some sort of legendary monster paleontologists grants Azula has a cast of the giant skull at his lab in the Yukon town of Whitehorse [Music] its huge size tells me that this animals built for power and intimidation we can see this large muscle attachment that runs down the back of a head the muscles attached to this jaw were powerful powerful if they could bite through almost anything and these car nasal tease these cheek teeth here would have been amazing bone cracking hammers so they came across a carcass a licen nice age madman or a horse could crack that bone get out the marrow and eat the fat in the marrow it was an amazing adaptation to take apart carcasses an amazing carnival this amazing collar or live 200,000 years ago in the Yukon it's still the Ice Age grasslands have blanketed the landmass triggering a population explosion of hoofed animals the short-faced bear has become the giant short-faced bear the largest ever to stop the earth it's colossal weighing almost 2,000 pounds standing 11 feet tall on two legs it can reach higher than a basketball hoop more importantly it has evolved a set of lethal weapons slender legs mean it can run at over 30 miles per hour faster than most horses inside its forehead the organ that controls smell is enlarged allowing it to sniff out a carcass six miles away combined with a bone-crushing jaws ient short-faced bear looks every inch the ultimate hunter [Music] evolution makes him massive with good reason competition for meat on the plains is intense [Music] this guy evolved huge because it needed to defend itself from other scary predators like lions wolves when Lions and wolves were running around the landscape they lived in packs but short phase bears are actually solitary creatures so they needed to be huge and intimidating to defend themselves and their food the giant short-faced bear will need its exercise for another reason life on the open prairie is about to get tougher soon it will face a battle for territory with a powerful rival history repeats itself once again 50,000 years ago frozen water at the poles resurrects the long disappeared land bridge between Asia and Alaska Beringia is back Beringia becomes a lush haven for migrating species from Asia [Music] lions elephants early man but most importantly the ancestor of black and brown bears the black bear simply can't compete on the plains of Beringia with big cats and larger bears however the ancient grizzly is feisty and powerful he challenges his distant cousin but the giant short-faced bear has no plans to share his fertile new land with a smaller arrival [Applause] the most dramatic phase of bear evolution starts 50,000 years ago back then Beringia is a landmass that links what is now Alaska to Siberia and acts as a gateway to the new world the ancestor to the Grizzly wants to migrate from Asia to this fertile new land the native giant short-faced bear is bigger stronger and has no plans to share it's a clash of the titans that will have only one winner the fossil record confirms that the brown or grizzly bear vanishes from Beringia thirty-five thousand years ago the giant short-faced bear sends it packing back to Asia [Music] the dramatic change in the fossil record of bears and Beringia is incredible the short-faced bear populations seem to explode while we have no record of grizzly bears at all seems like the competition for food resources amongst the carnivores was just too high for the grizzly bears they had to leave Beringia the giant short-faced bear dominates north america for over 1 million years yet we know that ultimately the grizzly bear returns to populate and conquer North America somehow it is found a way to overpower its larger enemy something unique will tilt the balance of survival in favor of the grizzly twenty-one thousand years ago the story of bear evolution in Eurasia and North America takes a dramatic turn the brown bear the ancestor of the grizzly has been muscled out of Beringia for thousands of years defending the corridor to the new world is the seemingly invincible giant short-faced bear but thirty thousand years after they first faceoff there's a rematch and this time a remarkably different outcome once again the Beringia fossil record reveals what happens it shows that suddenly twenty-one thousand years ago brown bears lived all over Beringia while the previously dominant giant short-faced bear has vanished [Music] something compelled these mighty bears to abandon their own territory [Music] [Applause] grants Azula finds clues to the mystery in the spectacular local topography halfway through the Pleistocene epoch their evolution is altered completely by the dramatic events in these mountains when these mountains surrounding Beringia here these were the accumulation centers for all the glacial ice that surrounded the continent of Beringia this is where the Ice Age began former inja massive sheets of ice accumulated here advanced over the landscape and creating an incredibly harsh cold icy aged environment well twenty one thousand years ago is considered the last glacial maximum this was the deep freeze that covered the earth this was the coldest time ever during the Ice Age probably the coldest temperatures that large mammals ever encountered the brown bears teeth allow it to eat meat and vegetation now it thrives in Beringia [Music] grizzly bears one here they they were able to survive and continue on until present day in Beringia the extreme cold drives hoofed animals out of Beringia the giant short-faced bears food source has gone the carnivore head south of the glaciers to the warmer climes of what is today the United States leaving the Gateway to North America wide open for brown bears [Music] over the next 11,000 years brown bears radiate all over North America where they continue to battle for supremacy of the plains [Music] but by now bears of the new world face a new enemy it's possible that conflicts could have arose between short-faced bears and humans the brown bear the giant short-faced bear and now man are rivals for food and shelter the biggest of every the giant short-faced bear will be wiped out yukon paleontologists grad Zazula has a theory as to why this house it has to do with one critical design flaw this evolutionary Achilles heel turns its enormous size into a deadly burden the most striking feature of the short-faced bear skeleton is that it has this large bulky mass on its trunk its chest area but when you look at its long limbs they're incredibly long but incredibly thin these are spindly little legs it's not something that can accelerate fast from a standing position or something that can be running at full tilt and turn on a dime so predators today and predators during the Ice Ages needed to be able to have that explosive turning power and explosive speed to chase down the herds of bison and horses in other words unlike the brown bear the giant short-faced bear cannot chase and catch prey instead the giant bear evolves a different strategy to find enough food to survive the short-faced bear would travel around the landscape using its highly evolved sense of smell to smell out the carry and these carcasses of mammoths and bison [Music] but those carcasses are also highly sought after by other predators as well the Lions the Wolves would have went after those carcasses for a free meal - so the short-faced bear had to be highly evolved to be really big so it can intimidate those other carnivores on the landscape scared away and had to look intimidating so this is an intimidating creature it was not built to fight it was built to look scary and that's exactly what it did when I got to its carcass and had to defend itself and defend its foot the giant short-faced bear isn't a super predator it's a super scavenger stealing the kills from other creatures [Music] early man such a trap for his greedy rival [Music] but which will triumph [Music] brain or bra [Music] climate is changing rapidly the environments changing rapidly and then people show up and it seems like a combination of several of these different types of factors may have been involved in the extinction of these guys [Music] ten thousand years ago the giant short-faced bear vanishes off the face of the earth in Eurasia the cave bear has dominated the animal kingdom for tens of thousands of years now it faces a new nemesis early man thing is that they lived in caves there's a great potential for interactions with humans and humans have had negative interactions with many of the other large animals that were around at the end of the lake lay shal period resourceful early man plays a role but there are other factors in the cave bears extinction [Music] there have been some studies that show that they did start to incorporate more carnivorous material into their diet so potentially that could have brought them into competition with other carnivores and they could have simply been out competed either way we know that ten thousand years ago man lived in caves and the cave bears were wiped out yet the smaller black and brown bears survive and flourish on both sides of the Atlantic today the brown bear is the most widely distributed bear on planet Earth and for good reason it can eat anything to kill prey it develops a large hump of muscle behind its shoulders it's been known to break the neck or spine of a bison with a single blow and it's reflexes are so well hold it's quick enough to stomp on mice with its feet its powerful legs in balance mean it can run faster than most horses [Music] well the thing about the brown bears of the Grizzlies they're extremely adaptable they have a behavior that allows them to be able to eat meat eat plants so they're an ultimate omnivore but the brown bears most dramatic transformation is arguably evolutions greatest story of all [Music] yot 200,000 years ago brown bears regularly invade these icy wastelands to hunt the appeal is large clumsy prey seals walruses and even the occasional trap whale then a sudden change of climate traps these brown bears in the Arctic they try but fail to make it back to their natural grassland habitat a population of grizzly bears becomes isolated from the rest of the pack somewhere in northern Eurasia in the Arctic regions they face a situation may either evolve or they perish their problems are numerous they are visible against the snow prey can see them coming their fur is not designed for such extreme cold there is little vegetation gradually they start to die out we had to figure out how to make a new way of life really fast so this is rapid evolution at its best to survive the brown bear turns into a super predator he evolves his nose to smell a seal 20 miles away a huge stomach he can eat 20 percent of his own bodyweight in one sitting [Music] he becomes invisible to prey [Music] trapped in the Arctic the brown bear evolves into the polar bear despite its appearance the polar bear skin is actually brown each hair of its fur is transparent designed to store heat but the reflection of snow and sunshine makes it look white it's strong enough to swim for 60 miles without taking a break [Music] the journey it has made to get here is incredible 20 million years ago the tree dwelling Don bear adapts to eat vegetation the Panda evolves to eat bamboo the sloth bear adds and termites the short-faced bear masters the plague the brown bear adapts to all these habitats and to ice having endured so much six bear species are now listed as vulnerable threatened or endangered as a result of human activity the Panda is running out of bamboo the sloth bear is running out of space and because of global warming the polar bear is running out of ice in recent years faced with a lack of partners and shrinking ice polar bears had begun to evolve in a new direction polar bears are mating with Grizzlies to form a new bear known as a growler this growler was shot by a hunter in Canada in 2006 look Rollers is a hybrid between a grizzly bear and a polar bear and it's maybe a new species something of a new type of bear that we've never seen on earth before it's evolution in action and we're seeing it take place before our eyes and it's not too often we get a chance to see evolution take place right in front of us you know what the Bears have a rich fossil history now we're seeing that evolution right in front of us taking place in the land in the north today you
