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Study guide 2-4 – Kottak, Chapter 10 & Film

Chapter 10: The Origin and Spread of Modern Humans 1. Explain the Out of Africa model of human migration. AMHs evolved from an African version of H. heidelbergenesis by as early as 300,000 years ago. AMHs spread to other areas, including Europe, where they replaced the Neandertals. a. Ethiopian discoveries: evidence from fossils, archaeology, and genetics confirms the African origin of AMHs; many sets of skulls and bones were found in African sites, many of them in Ethiopia, all in relatively close proximity to one another b. Jebel Irhoud, Morocco, and the earliest known AMHs: at the desert site of Jebel Irhoud in Morocco, scientists found AMH skull bones, tools, and evidence of cooking dating back to 300,000 B.P., and these fossils are now the earliest known members of our species; the ancient humans of Jebel Irhoud shared a general resemblance among themselves, their cranial capacity was as large as in modern humans, but their skulls were long and low like those of earlier hominins; the people of Jebel Irhoud were smart enough to make complex tools, such as flintbladed spears. Interestingly, their source of flint is located 20 miles south of Jebel Irhoud. These ancients knew how to find and use distant resources, and perhaps they could have participated in regional alliances and trade networks c. Israel’s Misliya cave: discovery of a fossilized human jawbone in a collapsed cave in Israel; dated between 194,000 and 177,000 B.P.; this is the earliest member of Homo sapiens found outside of Africa; this discovery provides support for genetic studies suggesting that some modern humans ventured out of Africa earlier than the migration that would eventually give rise to all living humans d. Other early AMHs: early AMHs have been found at South African sites, with some dating back to 120,000 years ago; AMH fossils have been found at Skhul, a site on Mount Carmel in Israel; early AMHs in western Europe often are called Cro Magnons; e. “Mitochondrial Eve”: UC Berkeley scientists gathered evidence supporting the hypothesis that modern humans (AMHs) arose in Africa, and then spread to the rest of the world; analyzed the genetic samples of 147 women whose ancestors came from Africa, Europe, the Middle East, Asia, New Guinea, and Australia; they focused on mitochondrial DNA and the number of mutations in the mtDNA; the variation in mtDNA was the greatest among Africans, which suggests that they have been evolving the longest; other evidence suggests a major migration of AMHs out of Africa around 70,000 years ago

f. AMHs on the move: there may have been interbreeding between Neandertals and moderns in the Middle East prior to the AMH colonization of Europe; Neandertals may or may not have coexisted with modern humans in the Middle East for thousands of years; the overlap in Europe apparently spanned the period between around 45,000 B.P. and Neandertal extinction around 39,000 B.P. 2. Outline the different theories relating to the advent of human behavioral modernity. Scientists continue to debate whether human behavioral modernity originated in Africa as early as 100,000 years ago or in Europe around 45,000 years ago; mounting evidence now tends to favor an African origin; as glacial ice melted and the Upper Paleolithic ended, foraging patterns became generalized; fish, fowl, and plant foods supplemented, then replaced, the diminishing big-game supply; the beginning of a broad spectrum economy in western Europe coincided with an intensification of Upper Paleolithic cave art; on limestone cave walls, prehistoric humans painted images of animal important in their lives; explanations of cave paintings (a prime example of human behavioral modernity) link them to hunting magic, ceremonies of increase, and documentation of hunting success a. The traditional view has been that modern behavior originated fairly recently, perhaps 45,000 years ago, and only after Homo sapiens pushed into Europe —> this theory of “creative explosion” is based on finds such as cave paintings b. There is an idea that human creativity dawned suddenly, and before then, Homo had changed very slowly in anatomy and behavior; after this “dawn of culture”, human anatomy changed little, but behavior started changing drastically c. Some attribute the rose of modern human behavior to increasing social competition than to population increase; competition could have produced new ways of sharing ideas and organizing societies 3. Recall the advances in stone tool technologies and the first appearances of cave art in the archaeological record. Stone tool technologies and cave paintings are important in understanding the development of Homo a. Stone tool technologies: toolmaking is associated with AMHs; Upper Paleolithic technology emphasized blade tools; the blade-core method was faster than the Mousterian and produced 15 times as much cutting edge from the same amount of material; Upper Paleolithic tools included knives, pins, needles with eyes, and fishhooks; with increasing technological differentiation, specialization, and efficiency, humans have become increasingly adaptable; through heavy reliance on cultural means of adaptation, Homo has become the most successful primate so far; the hominin range expanded in Upper Paleolithic times i. Upper Paleolithic tools vs. Mousterian tradition: the number of distinct tool types increased; increasing standardization in tool manufacture;

growth in Homo’s total population and geographic range and increasing local cultural diversity b. Cave art: the earliest cave paintings date back to 37,000 B.P.; more than 100 cave painting sites are known, mainly from a limited area of southwestern France and adjacent northeastern Spain; the most famous site is Lascaux, whose paintings were created about 18,000 years ago; most interpretations associate cave painting with magic and ritual surrounding the hunt; another interpretation sees cave paintings as a magical human attempt to control animal reproduction; cave paintings might also have been a kind of pictorial history i. Lascaux: discovered in 1940 by a dog and his young human companions; the paintings adorn limestone walls of caves located deep in the Earth; prehistoric big-game hunters painted their prey: wooly mammoths, wild cattle, horses, deer, and reindeer 4. Discuss the role that the ice ages played in the evolution of modern humans. The Wurm glacial ended in Europe between 17,000 and 12,000 years ago, with the melting of the ice sheet in Northern Europe; as the ice retreated, the tundra and steppe vegetation grazed by reindeer and other large herbivores gradually moved north —> some people also moved north to follow their prey; with most of the big-game gone, western Europeans were forced to use a greater variety of foods; to replace specialized economies based on big-game, more generalized adaptations developed during the 5,000 years of glacial retreat; as water flowed from melting glacial ice, sea levels all over the world started rising; during the Ice Age, so much water was frozen in glaciers that most continental shelves were exposed (few marine species could survive in this environment); as the sea level rose, conditions became more favorable to life in the shallower, warmer offshore waters, and the quantity of edits marine species increased; inland Europeans could now take advantage of new resources, such as migratory birds and springtime fish runs; hunting remained important, but south western European economics became less specialized; a wider range of plant and animal life was being hunted, gathered, collected, caught, and fished; plant cultivation and animal domestication replaced hunting and gathering in most areas 5. Describe the settling of the Americas, Australia, and Polynesia, including how current accounts depend on biological, linguistic, and archaeological evidence. As continental glaciers ebbed and flowed, modern humans took advantage of global climate change to expand their range; during the major glacial advances, with so much water frozen in ice, land bridges formed, aiding human colonization of new areas; people spread from Africa into Europe and Asia, eventually reaching Australia and much later, the Americas and Pacific islands; genetic markers, fossils, and archaeological sites help us understand the settlement process of humans into new areas; continental glaciation also created Beringia, the Bering land bridge that connected North America and Siberia; both branches of Native Americans diverged from those of Chinese people; the colonization of the Pacifics was accompanied by the spread of the earliest pottery found

in Oceania; improvements in canoes and marine technology allowed navigators to sail across large stretches of open sea, thus propelling the Polynesian diaspora 6. Define the following terms (and provide any examples from the text and lecture): a. Behavioral modernity- fully human behavior based on symbolic thought and cultural creativity b. Blade tool- basic Upper Paleolithic tool, hammered off of a prepared core c. Cro Magnon- the first fossil find (1868) of an AMH, from France’s Dordogne Valley d. Herto- early (160,000-154,000 B.P.) AMHs found in Europe e. Upper Paleolithic- blade-toolmaking traditions associated with European AMHs Film: Did Cooking Make Us Human? • What is on our plate is the most direct link we have with our ancestors —> “We couldn’t have become the dominant creatures we are without it” • 2.6 million years ago, our ancestors started to eat meat —> something we do every day has changed the course of human history • “Cooking is arguably the biggest increase in the quality of the diet in the whole of the history of life” • Some scientists are making three-million year old teeth chew again • 6 million years ago in Africa, humans started to walk upright • We know Austrolopithecus is a human ancestor because we have indication that it walked upright like humans, but otherwise it’s very ape-like; survived only a diet of raw fruit and vegetables • Spent a lot of time just chewing, similar to chimpanzees • Handy man/ H. habilis: associated with stone tools, brain expansion, smaller face that’s tucked up under the skull • 1.8 million years ago, our first truly human ancestor arrived: H. erectus • First early human that has really modern human-like characteristics • Big brain, and indication that it was a game hunter • Based on the experiment conducted with the eight volunteers eating a diet consisting only of fruit and vegetables (like Austrolopithecus), it was found that they just cannot eat the necessary amount of food • The diet does not provide enough energy for modern humans

• The volunteers lost a significant amount of weight, but if they would have kept up the diet, they probably would have died from starvation • Something must have happened to change our bodies since Austrolopithecus —> could eating meat really caused us to evolve? • About 2.3 million years ago, H. habilis, the first ancestor we think ate meat, appeared; H. habilis had a bigger skulll and a brain 30% larger than Austrolopithecus • “The Austrolopiths’ brain size remained stable, then meat-eating came in, and then the brains got bigger, and that set everything off in the direction of modern humans” • Meat is harder to obtain than fruits/vegetables, so some researchers think habilis did not have the ability to undertake the complex business of hunting • Jut’want, “real people”: their remote position means they have been relatively untouched by the 21st century • In this society, there is no farming, and everything they eat comes from hunting and gathering • Shows that the ancestors could have very well used very simple tools to hunt and catch their meat • Evidence reveals that the eating of meat changed our evolution forever. Our ancestors learnt to hunt, developed sharper teeth, and above all, grew bigger brains • Professor Richard Wrangham: controversial new theory that suggests it was not another change in the ingredients of our diet, but the way in which we prepared them that prompted the evolution of our first truly human ancestors • When people controlled fire it changed the diet • The acquisition of cooking was probably the most important increase in the quality of diet in the history of life, but certainly in the history of human evolution • Many scientists think that the ability to adapt to new environments and to interact successfully with those around them are also important influences • The reasons for the major step forward in our evolution are mired in controversy, but what is certain is that about 1.8 million years ago, the first ancestor whose behavior was truly human did emerge —> H. erectus • Our ancestors had gone from being preyed on by animals to using fire to frighten them away, and even to hunt them • The evidence that there was cooking 1 million years ago at the time of H. erectus is in the butchering marks of the bones

• The earlier the date, the greater the probability that cooking affected the evolution of our first truly human ancestors • When we cook something, a lot more of that energy is released during the digestive process —> cooking allows us to digest food easily, releasing huge amounts of energy into the bloodstream to power the body • The human ability to cook gives us a massive advantage over all other animals • Cooking changes the structure of food: it loosens the cells, it softens them, it allows them to be broken up in the mouth much more easily so that they can be digested later on • The discovery of cooking food gave our ancestors enormously more energy —> we don’t know exactly how much, but enough to have a huge evolutionary impact on survival and reproduction • Snake experiment: shows that eating cooked food reduces by a quarter the energy required to carry out the process of digestion • Professor Wrangham claims that this extra energy caused the dramatic adaptations in H. erectus • The small gut big brain theory was developed by paleoanthropologist Professor Peter Wheeler • “We think that the smaller digestive system in H. erectus was able to evolve because of the shift in diet, freed up energy which could be used to power a larger brain” • Humans use roughly 20% of our energy to power our brain, while most other primates use only 10% of their energy to fuel their brains • In humans, once cooking enable the gut to become smaller, then the energy spared from looking after the gut was made available to the brain • Seems likely that what cooking did was make those big brains possible • We in the modern world have used our hungry brains to create an environment in which we can eat what we want, where we want, and when we want • Modern humans have come a long way since our ancestors survived on a diet of raw fruits and vegetables • Our food has helped us overcome the disadvantage of being relatively puny • “But maybe it’s the discovery of cooking which has equipped us with brains big enough to take over the planet”...