"Seattle on the west coast of North America..." "One of the world's most high tech cities, it draws thousands of workers and visitors every day." "But how did the very first travellers get here ...and what would they have seen?" "When people first set foot in the northwest they were to encounter some of the most impressive beasts ever seen on the continent." "Using clues from the present to revisit the past, we reconstruct life in the far northwest at the end of the ice Age and discover how people and animals came face to face at the edge of the ice." "As we shall see from evidence left behind, people were present in North America 13,000 years ago." "But how did they travel here and where did they come from?" "The answers may lie in the northwest region of the continent." "ln this programme we uncover clues not only to a journey taken by people, but to a wilderness that they became part of... a wilderness that no longer exists." "ln doing so we get a glimpse of the life and death encounters in this corner of the continent at the end of the ice Age." "And we reveal how the northwest offered people a route into North America, which until recently was thought impossible." "It happened just as the huge ice sheets that covered most of the continent were breaking up... sometimes with a devastating impact on the people and animals living in the shadow of the ice." "Today we can examine the evidence of that dramatic era... using it to recreate the landscape and the wildlife of the distant past." "Bones and fossils can also tell us about the lives of the first people." "To get a picture of how much this region of the continent has changed since the end of the ice Age we must look at the present day landscape of the northwest." "Today this area is home to some of the world's most spectacular temperate rainforest... ranging 2,000 miles from modern day Seattle up into Alaska." "The Pacific northwest thrives on water more than three metres of rain falls every year to swell the forest rivers." "Mist and fog are as important to these coastal forests as rain." "All this moisture helps produce some of the planet's tallest trees towering 100 metres above the ground." "These ancient forests are one of the few true wildernesses left in North America and are home to creatures that have come to symbolise the wild." "But these dense forests aren't as old as you might think." "They certainly weren't here at the end of the ice Age 13,000 years ago." "The trees were sparser then and mixed with open grassland." "So were the animals that lived here different too?" "This small town in central Oregon has proved to be a window on the past." "Some of the region's most important fossil evidence has been unearthed beneath its streets..." "Bones like these help to paint a picture of the living creatures they belonged to." "This was the largest grazer in the Northwest, standing 4 metres at the shoulder... the Columbian mammoth." "And its biggest enemy the predatory scimitar toothed cat..." "As the great melt began, grazers and meat-eaters alike were faced with massive change." "Vast areas of land were transformed, gradually reviving after hundreds of thousands of years buried under the ice." "The glaciers we still see today in the North West are mere remnants of immense ice blankets that once dominated North America." "Their sheer scale is still impressive ... some are several miles wide, hundreds of metres deep." "But now the glaciers are in retreat, as they have been for over 13,000 years." "Remarkably, some of the icebergs set free by the melt consist of water frozen tens of thousands of years ago." "These floating fragments now provide a temporary resting place for harbour seals and their pups." "Imagine these glaciers at their peak... lt's thought they covered half the continent in layers almost 2 miles deep." "When the planet starting warming up, the ice sheets melted, usually over thousands of years." "But this process wasn't always slow and gradual." "This scarred landscape was created by one of the biggest flash floods the world has ever seen." "The waters from that flood scoured deep into the bedrock, and sculpted canyons such as these in Washington State." "These cliffs are known as Dry Falls." "They are geological ghosts reminders of the great flood that once swept across this region." "Around 12,000 years ago a giant ice dam in a lake 180 miles long collapsed under the weight of water..." "A huge wave up to 600 metres high raced across the land at speeds of more than 60 miles an hour." "This floodwater cut deep into the landscape, forming a giant waterfall several miles wide and more than twice the height of Niagara Falls." "The roar of the advancing tidal wave would have been heard by animals hundreds of miles away... as much as half an hour before it reached them..." "Two days later the lake was empty and the torrent started to subside, but by then millions of animals had died." "Some of the fossils found beneath the streets of Woodburn show it may have been hit by these floods." "And there may have been people living here at that time." "A strand of human hair discovered deep underground has been dated at around 12,000 years old." "While many stone tools from the ice age have been found, evidence such as hair is very rare." "The dating of the Woodburn hair is controversial but if correct, it represents one of the oldest human relics on the continent." "But is there other evidence to back it up?" "Another crucial hint that people did exist here as the ice age ended was discovered to the north of Woodburn on the Olympic Peninsula." "A two and a half metre long tusk was found... and led to the unearthing of a giant skeleton, recreated here." "Just the left hand side remained, but it was enough to identify one of the most impressive creatures of the ice age  a mastodon." "Mastodons, like mammoths, disappeared soon after the ice Age ended, and this skeleton revealed one possible reason why." "Between the ribs of this large male was found what seems to be a spear point... which implies this mastodon encountered human hunters." "A closer look reveals the rib bone healed around the injury... showing that even if the mastodon had been attacked, he survived." "Mastodons were distant relatives of woolly mammoths, but slightly smaller at around 3 metres." "It's thought that while the mammoths grazed the open grasslands, mastodons favoured patchy forests and swamps." "They moved in small herds, browsing on large shrubs and trees." "We know what they ate partly from the fossil teeth they left behind." "Their teeth had high, ridged cusps, thought to be used for grinding tough material like branches." "And plant remains found near the teeth suggest the mastodons preferred to dine on pines and other conifers, using their trunks to pull off branches, much like modern elephants." "Today the largest browsers on the continent are moose." "Moose weren't present in the northwest during the last ice age, but can their feeding habits give us an idea of how the mastodons lived then?" "Moose spend most of their time browsing on deciduous trees." "But at certain times of year they try something a little different... lt seems that water plants in lakes and ponds provide essential nutrients that moose can't get from trees." "Mastodon remains are often found preserved in ancient bogs and swamps suggesting they too may have varied their tree diet with seasonal water plants." "We know that mastodons and moose did not overlap in the northwest." "But if the large male found on the Olympic peninsula was victim of a spear attack, it seems that mastodons and people did." "But how did human hunters reach this area to start with?" "To retrace their steps we need to travel further north to the islands off the coast of South East Alaska." "This is Admiralty Island, famous for its brown bears." "Until recently it was assumed that 13,000 years ago it was covered in ice, just like most of the mainland." "But a recent study of Admiralty's bears reveals they are genetically different to those on the Alaskan mainland." "This suggests they must have been cut off here on the island for tens of thousands of years." "So could it be that Admiralty island was an ice-free zone during the ice Age?" "The genetic evidence suggests it was." "Bears are usually solitary creatures, but in summer they are drawn together by the need for food." "Mothers with spring born cubs begin to congregate around the coastal rivers, as they would have done during the ice Age..." "They're here to catch migrating salmon on their way upstream... ln these tidal shallows it's like fishing in a barrel." "For the cubs, it's time to look and learn as mother shows them how it's done..." "But sharpening those predatory instincts takes a lot of practice..." "The study of the Admiralty bears suggests these coastal islands may have been like stepping stones, allowing animals to move around during the ice Age.." "island hopping down the coast before arriving on the mainland." "And this idea is backed up by other evidence nearby." "This weathered limestone on Prince of Wales Island is riddled with caves." "And one cave in particular, recreated here, turned out to be a treasure trove of fossils." "Some of the bones found belonged to a large brown bear, dating from the peak of the last lce Age." "There were there other animals apart from bears." "ln the same cave on Prince of Wales island, a smaller skeleton was found ..." "An lce Age Arctic Fox... which would have used the cave to stash its food." "There were the scattered bones of seabirds too... probably leftovers from the fox's meals." "Foxes need open ground to breed and it seems that Prince of Wales island, like Admiralty, provided this during the ice age." "We now know some regions of the northwest coast offered an ice-free sanctuary throughout the ice Age." "So could people have been travelling between these islands too?" "The evidence suggests they were." "The Prince of Wales island cave also held the fossilised remains of at least one human," "including a complete lower jaw." "The position of the wisdom teeth suggests the jawbone came from a man in his early twenties." "But his teeth were deeply pitted for his youthful age." "What could have caused this damage?" "Again, the coastline seems to hold the answer." "There is a saying in Alaska that the tide lays the dinner table twice every day." "With each low tide the newly exposed rocks present a seafood platter." "And it's available all year round." "So shellfish would have been an easy and accessible source of protein for these early North Americans." "There's even evidence that they used bags and baskets to collect food along the coast." "But shellfish, while nutritious, can be very gritty." "Which may help explain the deep pits in the fossil teeth." "Chemical analysis of other bones seems to confirm that what the man ate did indeed come mostly from the sea." "And there are other clues relating to his death." "One of his hips was marked with scratches where did these come from?" "Perhaps a scavenger that found the young man's body... or were they made while he was still alive?" "Humans weren't the only animals that used caves for shelter." "The attacker may have been a bear... quite common in these caves during the ice Age." "Although the young man's bones date back just to the end of the last ice age, scientists think Prince of Wales island was probably inhabitable even earlier, when the mainland was still deep frozen." "These islanders were far removed from the cliche of primitive stone age man." "Able to sew and weave, they made different clothes for different seasons and even decorated themselves with jewellery." "But how did they first arrive here on these offshore islands?" "Their skills must have included making and navigating boats." "Exactly where they sailed from isn't certain but they may have come from Northeast Asia, island hopping across the Pacific until they hit the coast of North America." "At first they probably relied more on the sea's resources than the land." "They may even have traded goods between the islands." "But they didn't stay islanders forever." "As the mainland glaciers receded, a brand new land began to open up to them." "They may have travelled partly with the seasons, guided by the best time and places for fishing." "This spectacle would have been a golden opportunity." "Every year in early spring vast schools of herring gather off the coast to spawn, attracting sea lions from miles around." "These same events took place here 13,000 years ago and could not have gone unnoticed by the bands of seafaring hunters." "While the sea lions hunted herring, people no doubt hunted both." "As herring near the time of spawning they draw closer to the shore." "Here they begin releasing eggs and sperm into the tidal waters." "The sheer scale of this reproductive frenzy can turn miles of coastline milky white... just as it did during the ice Age." "As the ice Age glaciers melted and the rivers opened up, another kind of fish began to head inland." "Without the barriers of ice, migrating salmon penetrated upstream deep into the continent." "These freshly flowing rivers and the fish they carried lured people further inland too." "ln small groups they branched out to continue their passage into the new world." "They were continuing a journey that had started with their ancestors on the other side of the Pacific ocean somewhere in Asia." "These inroads brought their first contact with the large beasts of the continent including the Olympic Peninsula mastodon." "Although it seems to have survived its first attack by human hunters, there is evidence that in the end people dined on its meat." "Marks on its bones appear to show that it was butchered after death." "A large bull mastodon was quite a prize, alive or dead." "But if the hunters didn't actually kill the mastodon, what did?" "Another cave discovery reconstructed here has shed light on an ice Age predator that may have been the biggest enemy of mastodons and mammoths." "The scimitar-toothed cat." "Like its notorious relative, the sabre-tooth, the scimitar possessed long lethal canines... used to slash and kill its victims." "The inside of this cave is testament to its success." "More than 400 remains of baby mammoth and mastodon were found alongside the scimitar skeleton." "The fearsome canines had serrated edges and we can learn more about the scimitar's hunting techniques from its skull." "Like a modern cheetah, it had larger nasal passages than most cats." "ln the cheetah these deliver extra oxygen for short fast sprints." "A good grip is essential to the cheetah in a chase something the scimitar cat also possessed." "And like tigers, scimitars had powerful jaws helping them to dismantle the bodies of their prey." "These crushing jaws are also used to carry large kills back to dens." "Like most cats, the scimitar was probably a solitary hunter, and like generations of earlier occupants, it would have used this cave to store fresh carcasses." "This may also have been a birthing den, a safe place for the scimitar to leave its young while hunting." "ln the quiet of its hideaway, the scimitar could rest after a kill and this one, perhaps old or injured, seems to have come home to die." "Scimitar cats became extinct around the same time as the mastodons and mammoths another hint that they depended on the elephant-like creatures for their food." "But the evidence suggests these cats normally attacked young animals, making it unlikely that a scimitar killed the Olympic Peninsula mastodon." "So if it wasn't killed by human hunters or by a scimitar, perhaps this mastodon was not the victim of a predator at all." "Another theory comes from the bones themselves." "The cheek teeth used for browsing were extremely worn almost down to the gum." "A sign of heavy use over many years." "But this wear and tear may also have resulted from eating food outside the mastodon's normal diet." "Bones of grazers such as bison lay close to its skeleton, implying this was open grassland at the time." "Caribou were also found nearby creatures that also favour open spaces." "Today they live mainly on the tundra of the far north." "The presence of these other animals suggests the mastodon was not surrounded by its normal forest habitat." "Instead this area was treeless grassland grazed by caribou and bison." "Unlike a mammoth, mastodon teeth weren't designed for eating grass, which contains large amounts of erosive silica." "The silica may have destroyed this mastodon's teeth early and contributed to its death." "ln the end it seems this bull was probably a victim of a bad diet and old age." "Now we've seen the evidence, we're equipped to travel back in time, back to the end of the last lce Age 13,000 years ago... to experience a day in the life of the northwest, as witnessed by the first people." "This lake is a lifesaver for these mastodons." "It provides more than water." "As there are few trees to browse on, water plants are a valuable source of nutrition." "For some of these mastodons it's a temporary visit they will move on in search of open forests once they are well fed." "The search for food and water has brought a new arrival these people have used rivers to move inland from the coast." "This is the natural home of caribou and woolly mammoth... both tempting prey for these people." "They hunt smaller creatures too and use their fur for clothing to keep out the wind and cold." "These people bring many other skills and are highly adaptable." "But to most of the animals that live here, they are a new, unknown quantity." "As the ice begins to lose its grip, the land is in a state of flux and many different creatures mix." "The open grassy plains are favoured by mammoth herds." "But these mammoths have to share the lake with mastodons their smaller cousins." "While some of these mastodons are migrants, travelling onwards searching for fresh forests to browse." "For this old bull, at nearly 50 years of age, this is the last stop." "Weary and arthritic, he bears the scars of his long, arduous life." "The scimitar - a lion-sized cat is never far away from mastodons and mammoths." "Although slighter in build than its relative the sabre-tooth, the scimitar is the biggest predator of North America's elephants." "Right now, though, opportunities are rare even a scimitar cannot attack an adult in its prime." "But older animals, such as this feeble bull, could be potential targets." "A long and eventful life is drawing to a close." "Bull mastodons live most of their lives alone, but in their final hours they seem to attract company." "For a scimitar a mastodon near death is a temptation worth pursuing." "But mastodons, like many elephants, are fiercely protective of the dying." "For the scimitar, the mastodon's slow death becomes a waiting game." "The mastodon has died in peace, and now the scimitar has got his meal ... a feast that soon attracts further attention." "There's far more meat than this cat needs, but it's still loathe to let in others." "Against another cat, it holds its ground... but other hunters are arriving at the lake." "The scimitar is doomed to lose its meal and faces a potentially dangerous situation." "This is the first time this scimitar has encountered people." "On this occasion the cat gives way to these formidable new hunters." "Humans, like other animals, will find food where they can... and scavenging is one way to survive." "It's a time consuming task but these people are well equipped to butcher as much as they need." "The mastodon carcass could provide food for a later date it's not uncommon for meat from large kills to be prepared and saved." "ln the end they abandon what's left of the mastodon, and the carcass sinks into the boggy lake." "With it lies the story of its ice Age life and death... remaining buried until its discovery 13,000 years later in the northwest of modern day America." "Next week on Wild New World we visit the American Serengeti, home to lions, cheetahs and the giant short-faced bear." "ln the meantime, discover more about" "North America's lce Age wildlife at bbc.co.uk/nature."