100,000 BEFORE R T H N O

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1 4.5 MYA 3000 BCE BEFORE The ancestors of modern humans (Homo sapiens) colonized Africa, Europe, and western Asia. LIFE IN THE FREEZER The last glaciation (colder period) of the Ice Age, when many areas were covered in ice, lasted from 100,000 to 50,000 years ago. During this period, sea levels were far below modern levels and Siberia and Alaska were linked by land. It was also drier than today and tropical climates were slightly cooler This was followed by a slightly warmer period before a return to extreme cold about 18,000 ICY LANDSCAPE years ago. ORIGINS OF MODERN HUMANS The original ancestors of modern humans evolved south of the Sahara Desert in tropical Africa. The scattered human population was very small, and groups developed in isolation from each other. EARLY MAN ON THE MOVE Early Homo erectus fossils 19 indicate that they had settled in western Europe by 800,000 years ago. Neanderthals 19 spread into Europe and western Asia by 200,000 years ago. FLINT HAND-AXES This technology, developed in Africa 2.5 million years ago, was used for millions of years ,000 FLINT HAND-AX The number of years since small groups of humans began to leave Africa. By 60,000 years ago genetically modern Homo sapiens were colonizing the Earth. Mammoth cave painting The walls of Lascaux Cave in France are alive with bison, mammoth, wild oxen, and stag. Cro-Magnon artists (see p.26 27) painted these powerful, ageless images in this Ice Age treasure trove of art some 17,000 years ago. Out of Africa Every human today is the descendant of a small group of modern humans who left Africa around 60,000 years ago to explore the planet. We can see the legacy of these journeys today in the diversity of races and cultures around the world. S ixty thousand years ago, modern humans (Homo sapiens) were confined to tropical Africa and a small part of southwestern Asia. These were people with the same physical and mental abilities as ourselves, hunter-gatherers capable of adapting to any environment on Earth, be it one with nine-month winters and subzero temperatures, or steamy tropical rainforests. Then, during the last cold period of the last Ice Age, the most significant of all human migrations out of Africa began. Toward the end of the Ice Age 15,000 years ago, this vast population movement was complete. Late Ice Age hunting bands had settled all of mainland Africa and Eurasia and had crossed, or were about to cross, into the Americas. Homo sapiens had mastered tropical waters with canoes or rafts, had drifted or paddled to New Guinea and Australia, and penetrated as far south as Tasmania. Survival of the fittest Earlier forms of humans such as Homo habilis and Homo erectus had long vanished from Earth, forced into extinction on marginal lands where food was not plentiful, or killed by the newcomers, with whom they could not compete. Colonizing the planet was not a deliberate project, undertaken by men and women set on occupying new lands or exploring the world that lay beyond their hunting territories. Rather, the complex population movements that took modern humans to the limits of the harsh late Ice Age world came about as a result of the necessities of hunting and plant collecting in a great diversity of natural environments. In more northern climates, meat was the staple food, while tropical and temperate groups made considerable use of wild plant foods. The secrets to survival were adaptability the ability to adjust to sudden changes in climatic conditions by technological innovation and sheer ingenuity, mobility, and opportunism. People responded to food shortages, drought, or extreme cold by moving elsewhere in a world where the total global population was perhaps no more than five million people, scattered in small groups over hunting territories large and small. Many people may not have encountered more than a few dozen fellow humans during their lives, although we can only speculate about this, as the population figures can only be educated guesses. Evidence of migration Dozens of archaeological sites caves, rock shelters, open camps, and huge garbage heaps, or middens, of seashells and freshwater mollusks document the great journeys made as humans spread around the globe. Klasies River Mouth in South Africa is one such site where caves were used as shelter by modern humans about 120,000 years ago, showing that by that date the first modern people had traveled from their origins in northeastern Africa (see pp.18 19). The techniques of molecular biology are another way in which we can learn more about the movement of these early humans. By comparing certain strands of DNA (the substance found in every human cell that determines the characteristics we inherit), we can 1 MILLION The estimated human population of Earth 500,000 years ago. work out how Earth was colonized by Homo sapiens, and when splits in the population occurred. This was a complex process involving constant movement by small numbers of people. We are only just beginning to comprehend the process of colonization, but one thing seems certain: all non- Africans are descended from what American biologist Stephen J. Gould once called a single African twig on the human family tree. All people alive today have their ultimate roots in the so-called African Eve of some 150,000 years ago. This name stems from the fact that MtDNA (mitochondrial DNA) was passed from mother to offspring through every generation since the first Homo sapiens. We all share genetic information with Eve, with each other, and with our ancestors (see p.27). Human migration This map shows key sites for our early ancestors, as well as the routes that Homo sapiens is thought to have taken from Africa around the world. S O U T H Clovis A M The earliest known settlement in South America dates from about 13,000 years ago. Finds from the site, at Monte Verde in Chile, include stone tools for chopping, scraping, and pounding. E R N O 12,000 YEARS AGO Meadowcroft Cactus Hill R T H Big game hunters The people associated with Clovis hunted big game. Their presence in America about 12,000 years ago coincides with the extinction of several large species including mammoths, mastodons (a mammothlike species), and giant sloths. 12,000 YEARS AGO I C A Monte Verde 24

2 OUT OF AFRICA Kennewick A M E R I C A 15,000 YEARS AGO Beringia Land Bridge KEY Migration of Homo sapiens around the world Site of early Homo sapiens find Site of early Hominin find This mammoth bone carving found at Dolní Vestonice was made by hunters between 28,000 and 22,000 years ago. This archaeologist holds the remains of Homo erectus, which dates from about 1 million years ago, and was found on this site. The first modern humans in China occupied this site by about 40,000 years ago. 25,000 YEARS AGO P A C ATLANTIC OCEAN Boxgrove Lascaux Altamira Atapuerca Schöningen E U R O P E Dolní Vestonice Le Moustier 45,000 YEARS AGO Dmanisi Shanidar Zhoukoudian A S I A 50,000 YEARS AGO I F I C O C E A 60,000 YEARS AGO N A F R I C A Niah The cave paintings of Altamira date from about 15,000 years ago and are famous for their dramatic representations of bison, boar, and red deer in charcoal and earth pigments by people of the Magdalenian (Paleolithic) culture of southern Europe. Hadar 160,000 YEARS AGO Huerto West Turkana Koobi Fora Lake Turkana Olduvai Nariokotome Laetoli 120,000 YEARS AGO Lucy (Australopithecus afarensis) was found in Ethiopia in 1974, dates from about three million years ago, and is an important example of an Australopithecus (see pp.16 17). This area of northeastern Africa is rich with early hominin remains and continues to yield finds that provoke new theories about our own evolution. INDIAN OCEAN Flores Sangiran Malakunanja 45,000 YEARS AGO L I A Blombos Cave Klasies River Mouth Caves in South Africa were occupied by hunter-gatherers c. 120,000 years ago and have revealed some clues about how they lived. Some of the earliest known remains of Homo sapiens were found in the caves. Klasies River Mouth The earliest finds in Australia come from Lake Mungo. Tourists today visit a landscape of strange formations where over 20,000 years ago there was a lake and much human activity. Stone tools and animal bones found in the area have shown us much about the first Australians. A U Lake Mungo S T R A 25

3 4.5 MYA 3000 BCE Sometime after about 50,000 years ago, when glacial conditions in the north had improved and the climate was more temperate, modern humans moved into Europe and Asia. Tiny numbers of people were involved in the hundreds but by 45,000 years ago they were well established in the eastern European plains and in the Don Valley, now in Ukraine, and were moving rapidly across Central and Western Europe. The Neanderthal controversy Homo sapiens had settled alongside Neanderthal bands that had already been in Europe for about 200,000 years. DNA research on Neanderthal bones suggests that the newcomers did not interbreed with them, as had previously been believed. One theory is that Europe s indigenous inhabitants died out because they lacked the adaptability, mental abilities, and technology of modern humans. They survived in some parts of southeastern Europe until as late as 24,000 years ago before becoming extinct. A thriving European culture From about 40,000 to 10,000 years ago, a remarkable array of sophisticated, cold-adapted hunter-gatherer societies flourished in Central and Western The bone house This reconstruction of a shelter built from mammoth bones is based on the remains of a dwelling that was found by archaeologists in modern-day Ukraine. It demonstrates the ingenuity and adaptability of early humans to local conditions and resources. Europe. These Cro-Magnon people named after a rock shelter near Les Eyzies in southwestern France were opportunists. They relied for their subsistence on a range of plant foods and fish, taking advantage of salmon runs, for example, when the rapidly changing climate of the late Ice Age allowed. Their success came not only from their superior mental abilities, but also from their ingenious multipurpose flint tools, which worked almost like a modern Swiss Army knife. They used carefully shaped flint nodules to produce standardized, parallel-sided blanks, which they then turned into points, scrapers, and other tools. One of these artifacts a chisel allowed them to cut grooves in reindeer antlers, thereby unlocking a new technology for manufacturing harpoon heads, spear points, and other hunting weapons. Barbed, antlertipped spears were especially effective on reindeer and other game. The Cro-Magnons produced other revolutionary items, including the spear thrower a hooked stick that vastly increased the distance a spear could be thrown. They successfully used this new technology to hunt a wide range of Ice Age animals, including bison, mammoth, and woolly rhinoceros. The eyed needle was another remarkable invention (see below). These people were also skilled artists and developed a distinctive visual tradition, which amplified their elaborate rituals and beliefs. One of the most famous examples of their art comes from the cave paintings of Lascaux in southwestern France, which are on a huge scale, and renowned for the skill of the artists who created them INVENTION THE NEEDLE The eyed needle was a groundbreaking invention. As early as 30,000 years ago, late Ice Age people in Europe and Asia made needles from polished bone and ivory slivers, perforated with sharppointed flints. They sewed tailored, layered garments that enabled them to work outside in freezing temperatures. It is believed that, like modern Inuits, they used cured and softened animal pelts, sewing the seams with fine thread made of animal and plant fiber. Without tailored clothing Homo sapiens would never have settled the Eurasian steppes or colonized the Americas. The longest journey The first Homo sapiens left Africa to colonize the planet about 60,000 years ago. By the end of the Ice Age 10,000 years ago, they had reached all the continents except Antarctica, adapting to different conditions wherever they went.

4 OUT OF AFRICA (see pp.20 21). For the first time, people had the skills to live in harsh environments like the Eurasian steppes, where there is little rainfall and dramatic changes in temperature with hot summers and very cold winters. Despite these skills, the Cro-Magnons appear to have moved south into sheltered locations, only moving north again as temperatures rose. Some of them constructed elaborate dwellings, like the intricate mammoth bone houses at Mezhirich in modern Ukraine (see left), built partially into the ground and roofed with hides and sod. Toward the end of the Ice Age, about 12,000 years ago, human society became more elaborate, as populations grew larger and new areas were colonized. HOW WE KNOW ADAPTING TO CHANGE Study of the genes of modern populations can help to show how the early humans colonized the planet. Mitochondrial DNA, inherited through the maternal line back to a fictional Eve (see p.24), can be traced from an ancestral tropical African population to today. The male Y chromosome can also be used to trace through generations. From this evidence we know that 99.9 percent of the genetic code of modern humans is identical throughout the world. The differences in facial features and coloring are down to minor genetic mutations that have taken place over the last 150,000 years. Amazingly, the world s population outside Africa can trace their genetic history back to perhaps as few as 1,000 individuals who made the journey out of that continent. Chromosome mutations can be used to show when groups arrived in different parts of the world and to construct a genetic family tree that goes back to the Ice Age. A hunter s tool kit As humans traveled around the globe and experienced different environments and climates, they adapted their weapons and tools to survive. These bone tools, found in France and dating to between 18,000 and 10,000 years ago, were used by hunters in Ice Age Europe. Siberia and the tundra Homo sapiens migrated north from southwestern Asia and colonized the river valleys of Central Asia around 45,000 years ago. Small bands lived permanently in the bitter cold of the steppe-tundra a windswept landscape featuring low-growing vegetation that extended from central Europe all the way to Siberia far to the northeast. Enduring long winters, each band anchored itself on shallow river valleys like those of the Don and Dnieper in Russia, subsisting for the most part on animals such as the saiga antelope and large game, including the arctic elephant and the mammoth. Between 35,000 and 18,000 years ago, some hunting bands moved northeastward across the steppetundra into the Lake Baikal region of Siberia and farther to the northeast. Some moved to, or formed, new groups, while others moved to find new hunting grounds or natural resources. A variety of circumstances linked to hunting and survival contributed to the movement of tiny numbers of these late Ice Age bands across an extremely inhospitable landscape. Such natural population movements led to vast areas of the globe being colonized. Even earlier, from around c. 60,000 years ago, other groups moved east from northeast Africa and southwestern Asia into what is now India and Pakistan, and into the tropical forests of Southeast Asia. We know little of these movements the groups probably skirted the Eurasian

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6 OUT OF AFRICA FLORES FIND Excavations in 2003 at Liang Bua Cave (right) on Flores Island, in Indonesia, yielded the remains of a tiny skeleton standing about 3 ft 6 in (1 m) tall. The bones display a unique mix of primitive and more advanced characteristics, and date to about 18,000 years ago. With a small skull (below), large brow ridge, and a delicate face, Homo floresiensis had slight legs like some early hominins, yet modern teeth. Questions have been raised over whether this is a separate species or a small Homo sapiens. Others suggest this is the remnant of a Homo erectus population, or the descendant of humans who drifted to the island, then developed unique anatomical traits in isolation. Unless more remains are found, Homo floresiensis may remain an intriguing, unsolved mystery. HOW WE KNOW deserts and settled in northeastern China by 25,000 years ago, after the warmer south part of the continent had been explored. Sunda, Sahul, and Asia During the late Ice Age, a huge continental shelf an area of land connecting the continents that is now covered by higher sea levels known as Sunda extended from mainland Southeast Asia far into the Pacific. Only short stretches of open water separated New Guinea and Australia from this now-sunken land. Another landmass, Sahul, linked Australia and New Guinea themselves. Homo sapiens arrived in mainland Southeast Asia before 50,000 years ago. By 45,000 years ago the date is controversial a few hunting bands had crossed open water to Sahul and colonized what is now Australia. They may have crossed on primitive rafts or in dugout canoes. Modern humans had settled New Guinea by about 40,000 years ago, and crossed to the Solomon Islands by about 5,000 years later. Huntergatherers had settled throughout Australia, including Tasmania, by 30,000 years ago. This was the outer limit of human settlement of the offshore Pacific until outrigger canoes (see pp ) and open-water navigation techniques allowed people with domesticated animals and root crops to make the lengthy open-water passages Oldest footprints Hundreds of human footprints, preserved for over 20,000 years, have been found at Lake Mungo, Australia. At that time, the lake there would have been home to fish, mussels, and crayfish all valuable food sources. after 1000 BCE. The evidence of human life at Lake Mungo in Australia reveals details of hunter-gatherer life about 40,000 years ago. It is important as it captures a moment in time and a lifestyle that remained largely unchanged for thousands of years. Reaching the Americas Archaeologists have disputed the date of the first settlement of the Americas for over a century. Most now agree that native Americans originated in Siberia. Genetic and dental evidence links the two areas and backs up this theory. There are also linguistic ties that hint at population movements from Siberia to Alaska. But it is not known precisely when and how the first settlement took place. Until about 10,000 years ago, a low-lying land bridge, Beringia, joined Siberia to Alaska Clovis points North American hunters made these flint spearpoints over 11,000 years ago. They are some of the few objects found from this early period. They would have been used to kill and cut up large prey such as mammoth. (see pp.24 25). Most scientists believe that the first Americans were Siberian hunters who crossed this bridge into Alaska at least 15,000 years ago, toward the end of the Ice Age. Route south More controversy surrounds the route by which the first Americans penetrated the heart of North America, something which is thought to have taken place at least 13,000 years ago. Huge ice sheets covered most of what is now Canada. One theory favors a movement south along the continental shelves of southeast Alaska and British Columbia, which was then a landscape of steppe-tundra. Another common hypothesis claims a rapid movement south along a narrow corridor between two ice sheets, one mantling the Rocky Mountains and the other extending east toward the Atlantic. The controversy is unresolved, but we know that small numbers of early American hunter-gatherers were south of the ice sheets, and some as far south as Chile, by at least 13,000 years ago. The early Americans are best known from the remains of kills of bison, mammoth, and mastodon in North America. They are often labeled biggame hunters, which is misleading, as they relied on plant foods and adapted to temperate and tropical areas, as well as the bleak lands at the margins of retreating ice sheets. They did prey on indigenous species of large mammals, but, by 10,500 years ago, most of this megafauna was extinct, probably as a result of drier climatic conditions, perhaps speeded by some overhunting. Early evidence The archaeological record of the early Americas is sketchy. Key sites include a 12,000-year-old rock shelter in Meadowcroft, Pennsylvania, a scatter of stone tools from a site at Cactus Hill, Virginia, and a well-documented foraging camp at Monte Verde, Chile, dating to about 13,000 years ago. The first welldefined culture is that of the Clovis people, famous for their fine flint tools, who flourished between about 11,200 and 10,900 years ago. One controversial discovery is a 9,500 yearold skull from Kennewick, Washington State, which is believed to have caucasian features and may be an indication that some of the first settlers in America came from Europe. However, this has been the subject of much debate. By 10,000 years ago humans had spread to every continent (except Antarctica) and had learned the skills needed to survive in different environments. Later explorers found their new world already inhabited by the descendants of those first settlers. ADAPTING TO CHANGE American Indian societies adjusted to warmer, often drier conditions, by intensifying the search for food, whether it be fish, game, or plant foods. By 4000 BCE, some foraging groups were experimenting with the planting of native grasses 36 37, such as goosefoot. EUROPEAN SETTLERS IN AMERICA ATLATL LATER EXPLORATION Europeans first came in contact with American Indians 500 years ago when they traveled the world in search of new land 230. Dutch settlers arrived in Manhattan in the 1800s and traded with the native population before establishing a permanent settlement there. AN ISOLATED CULTURE The culture of the Australian Aboriginals developed in virtually complete isolation. Like other huntergatherer societies, they have a complex relationship with their environment and elaborate spiritual beliefs. ABORIGINAL HUNTER INVENTION AFTER Atlatls (from an Aztec word) are throwing sticks or spearthrowers, first developed by Cro-Magnon hunters over 20,000 years ago. Spear throwers increase a spear s range and velocity useful qualities for hunters who rely on stalking to kill their prey. The simplest atlatls are hooked sticks. A weight adds stability and velocity to the throw. Such weights, often called bannerstones, are often found on native American sites, as they arrived with the first inhabitants of the region. The Aztecs later used them against Spanish conquistadors (see pp ). 29