"First, our ancestors walked upright." "They survived by becoming scavengers and opportunists... but this creature is something new." "He has taken the next step on the journey to becoming human." "This is the story of what makes him like you." "I'm travelling back in time." "With science, we can build a picture of our past... and bring our dead ancestors to life." "Join me on a journey through our human story." "Southern Africa, one and a half million years ago." "These people are Homo ergaster." "For two days, they've been tracking an ageing wildebeest." "They've literally walked it into the ground." "Dee!" "Yet the hunt is far from over." "The wildebeest is exhausted but not dead." "Only experience will tell them when to strike." "Dee ajooti!" " A-wah." " Ajooti." "(HE YELLS)" "(THEY YELL)" "(BELLOWS)" "Hah!" "Racog!" "Hah!" "Racog!" "A waste of effort." "Argh!" "The young male's impatience has cost the ergaster their kill." "Their hunger will have to wait." "By looking at the bones and relics that these people will one day leave behind, modern-day scientists will get a good idea of the part they play in the evolution of you and me." "And by being here, in Africa, one and a half million years ago, you and I can do something else." "By watching their everyday lives closely, we can see the seeds of humanity developing in these apemen, and also, we can see how much of the apeman remains alive in us." "First of all, though, we have to keep up!" "It's twelve noon and 35 degrees in the shade... but ergaster can cover vast distances at quite a speed even in these conditions, because they have the most sophisticated cooling system of any animal on Earth." "Long modern-looking noses cool and moisten the air as they breathe." "Hairless bodies let heat escape... and millions of tiny glands in their skin mean they don't pant to control their temperature, but sweat." "So while other animals sit it out in the shade, ergaster can stride out in the sun." "And they have another adaptation, something you can't see - an enormous brain." "In fact, it's from ergaster that we inherit our big brains." "Perhaps we can find out why we both share such a unique adaptation by seeing what ergaster use their big brains for." "To start with, by using their big brains, ergaster can understand the world around them like no creature has ever done before." "In fact, their insight into their surroundings is nothing short of revolutionary." "For you and I, experience of the natural world can be little more than passing, but for all other animals, our ancestors included, life itself depends on it." "All animals have some understanding of their environment." "A five-month-old swallow can instinctively negotiate the 10,000-kilometre journey from Britain to South Africa without ever having done it before." "An old matriarch elephant can remember a place to find water in the driest of seasons even if she's only been there once, half a century earlier." "But until now, no creatures have pieced together knowledge of their world from apparently unrelated clues found around them." "No creature has ever been able to look at marks like these in the mud, for instance, and, never having seen them before, know anything about them at all." "It sounds like the simplest thing imaginable, and to you and I it is, yet, though it may surprise you, to a dog, cat or even to a baboon, these marks are no more than the pattern on the world's carpet." "Of all the creatures on Earth, only you and I can look at these marks and tell them for what they are - hoof prints, made by an animal that went thataway." "Ergaster is the creature we get that skill from." "For them, it's the key to unlock nature's secrets." "They can understand there's a particular kind of cloud that signals rain that the arrival of a new type of bird, like our swallows, means a change in season and new opportunities." "Even if they've never seen a particular kind of animal before, they can still place it within the jigsaw of their world." "Though there will always be mysteries, ergaster's new way of seeing the world is a milestone on the journey that will lead to us." "To understand the world is a vital step towards controlling it." "(SHOUTS)" "And bigger brains have allowed ergaster to do something else." "They've made an extraordinary technological breakthrough." "They've created the Rolls Royce of stone axes." "Heavy and powerful, yet precise enough for delicate cuts." "It shows both planning and vision, and because they're found all over Africa, it shows that these people could learn from each other the secret of how to make them." "A million and a half years before your time, this axe is the most sophisticated object on the planet." "So, ergaster's big brains have completely changed the way they live, but surprisingly, we still haven't seen the real task they and we use our big brains for." "A big brain is an incredibly expensive thing to run in terms of the amount of energy it uses." "Ergaster's brain is so energy hungry it consumes about a sixth of all the calories they eat and drink in a day." "For such a gas-guzzler to be worthwhile, it must be absolutely vital for these people's survival." "And indeed it is." "They need it to deal with the most complicated thing in their world." "And the really complicated thing about ergaster's world is the same as the really complicated thing about ours." "It's not tools or tracking, nor judging when a wildebeest is ready to die." "What you need a big brain for is understanding other people." "Ergaster work together to find their prey, stalk their prey, and kill." "They will even take some food back to share with other individuals in their group." "Meat is not simply food, it's a potential bargaining tool for later." "For the young male, the stolen crocodile tooth may also come in handy." "Almost everything about ergaster has brought surprising benefits in their complex new world of relationships..." "(PANTS) ...like the fact they sweat instead of pant to lose heat, even when they're working hard." "This has given them much more control of their breathing, freeing up their body for something incredibly useful." "It frees up their body to make sounds." "(THEY SHOUT TO EACH OTHER)" "Ergaster are the first of our ancestors to have what we would recognise as a human voice, and using it to communicate with each other has become crucial to their way of life." "So much so that, if you were in Africa one and a half million years ago looking for a group of Homo ergaster returning home after a successful hunt, the chances are that long before you'd see them, you'd hear them." "(MALES SHOUT TO EACH OTHER)" "(THEY CHANT)" "Ergaster don't have permanent home bases." "Instead, they drift from place to place, depending on where they can find food." "Each can feed themselves from what they gather about them..." "(HUNTERS CHANT)" "(WHOOPING CALL) ...but the return of the hunters with the potential of meat to share is a special event." "(THEY SHOUT)" "(WHOOPING CALL)" "This is a scene unlike any on Earth before - a group of animals held together not by safety in numbers nor by an individual male, but by something potentially much more powerful " "the ties of family and friends." "Helping others, and relying on others to help you, has become the glue holding people together from a mother offering food and support to her pregnant daughter to the beginnings of a new kind of relationship " "males and females, pairing up and living for at least a time monogamously." "To help them in this new world of depending on each other, ergaster have developed a unique mutation." "Ayi darshi!" "We think that they are the first of our ancestors to have very noticeable whites to their eyes, like ours." "Darshi!" "Oo voozu?" "Like us, they can see into each other's minds..." "Darshi!" "Keema hoot!" "...and communicate, at a glance, hidden depths of meaning." "Voozu." "For the young hunter, his portion of the kill is more than just food, it's a currency." "He's going to use it to buy a mate." " Wa-ha?" " Chiccatoo." "Chiccatoo." "The stolen tooth only adds to the good impression." " Borjoo!" " Borjoo." "He's a man who is not only useful, but also brave." "Quite a catch!" "But the young female appears to have more than one potential suitor." "For any ergaster, there are few more unsettling sights than a solitary, unattached male." "(AGGRESSIVE SHOUTING)" "The primitive eruption of violence is both sudden and shocking... yet it's part of these people's complex lives together." "To have a society where there are not only enemies but more importantly friends, has given ergaster tremendous potential." "Together with their new command of their environment, it has enabled them to do something which has never happened before in the history of human life on Earth." "It has given them the competence to leave their ancestral home, Africa, and to begin to populate the rest of the world." "They began by following the course of the River Nile across Africa and into the Middle East." "Their numbers growing, they travelled further as they searched for food reaching Asia, the first of our ancestors to tread on this side of the earth, as far as the southern reaches of China." "Their epic journey took thousands of years, and so far did they travel that when we find them, we even call them a different name" " Homo erectus." "It is these people whose eyes are the first to see the wonders of the eastern world." "(THEY YELL)" "It's a curious fact that when we find evidence of these first Asians, we never find the elaborate stone axes their cousins in Africa made use of." "It could be they found a different tool, easier to work, and in this vast kingdom, all around " "bamboo." "Erectus live in a land where tools grow like trees." " Bedeck!" " Bedeck!" "(SQUEALING)" "Small deer and pigs are everywhere in the dense bamboo forests but erectus are not fussy." "Te!" "Guloo!" "Oot!" "Oot!" "They can easily rethink the menu." "In time, our ancestors will change the world as no animal before." "Many creatures that get in their way will be swept aside, but not today." "For all the confidence of erectus, there are still things in this new world with the capacity to scare like the massive Gigantopithecus, an ancient ape, three metres tall - the original King Kong." "(THEY YELL)" "But in time, the balance of power will shift." "Dobey chay?" "Erectus are tough and adaptable, and in this ancient Asian landscape, they'll do well." "So our big-brained ancestors are flourishing all over the planet." "It might seem as if the modern world isn't far off at all but think again." "Travel with me in time, forward a million years, and I'll show you something remarkable " "a mystery which shows how hugely different these ancestors really are from you and me." "We're in Africa again." "We've moved forward a million years, but our ancestors haven't moved forward at all." "This is a recently-abandoned kill, butchered by our ancestors a million years after we saw them using their original stone axes." "And what are they using now?" "It's another stone hand-axe, astonishingly, exactly the same as the axes which ergaster made a million years before." "In all that time, their technology hasn't advanced by one degree." "It hasn't even occurred to them to do something as simple as to stick this axe on to the top of a pole to make a spear." "In modern times, we've gone from the Wright Brothers' first powered flight to space exploration in less than a hundred years, from telegrams to text messages in less than ten." "Ergaster has achieved nothing new in a million." "Can you imagine such limited ingenuity?" "Our ancestors make an axe like a bird builds a nest." "They don't think about it, they just do it." "It's no more possible for our ancestors to invent better technology than for that bird to decide to cover its nest with a roof." "It's not that our ancestors are stupid, their brains just don't work like ours do." "It takes something extraordinary to change this way of thinking - a trigger to set our ancestors' minds racing - and it may be we know what it is." "We don't know precisely where it happened or when, but some time around now, our ancestors encountered this." "They would certainly have seen fire before, from lightning or bush fires, but there would have been a moment when they learnt to harness it for warmth, for safety, as a tool, and then their lives changed." "Suddenly, like no animal before them, they control their world... and nightfall doesn't bring danger but something new - time outside the struggle for survival, time for the mind to wander." "Perhaps they felt something like we do if we stare into flames in our own time." "Indeed, perhaps it's the shadow of their prehistoric thoughts which comes to us when we do." "And could it be that fire changed not only the way our ancestors lived, but how they could think?" "That it broke the shackles in their minds and let their ideas fly free?" "That fire, in future generations, helped them become us?" "We'll never know, but certainly, here in the safe glow of such an elemental force, anything does indeed seem possible." "Next on "Walking with Cavemen", a battle for survival in a desperate world, and the mysterious gift that completes you and me."