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This chapter reviews previously published palaeovegetation and independent palaeoclimatic datasets to determine the responses of Amazonian ecosystems to changes in temperature, precipitation, and atmospheric CO₂ concentrations that occurred since the last glacial maximum (LGM), about 21,000 years ago, and it uses this long-term perspective to predict the likely vegetation responses to future climate change. Amazonia remained predominantly forested at the LGM, although savannas expanded at the margins of the basin. The combination of reduced temperatures, precipitation, and atmospheric CO₂ concentrations resulted in forests structurally and floristically quite different from those of today. Evergreen rainforest distribution increased during the glacial-Holocene transition due to ameliorating climatic and CO₂ conditions. However, reduced precipitation in the early-mid Holocene (about 8000-3600 years ago) period caused widespread, frequent fires in seasonal southern Amazonia, with increased abundance of drought-tolerant dry forest taxa and savanna in ecotonal areas. Rainforests expanded once again in the late Holocene period as a result of increased precipitation. The plant communities that existed during the early-mid Holocene period may constitute the closest analogues to the kinds of vegetation responses expected from similar increases in temperature and aridity posited for the 21st century.

The domestication of the earth entails the enfolding of ‘nature’ into human life and society. This chapter focuses on the millennia of the Holocene, when human societies consisted of food collectors and agriculturalists who essentially lived off recently fixed solar energy. In the course of its last 100 years, geography has from time to time taken in, and focused its attention on, diverse approaches to its subject matter. But as a ground bass to these variations, the relation between humans and the environment has persisted, though sometimes virtually at sotto voce level. In part, geography's attention has concentrated on landscapes as visible demonstrations, past and present, of these interrelations, but it has also taken an approach based explicitly on late-twentieth-century ecological theory. This chapter examines humans as hunter-gatherers during prehistoric times, along with the emergence of agriculture in Britain.

This chapter explores the dynamics of plant and animal species and species assemblages during the Earth's most recent period of rapid warming to garner insights into the potential consequences of future rapid climate change. From the perspective of climate change ecology, the Late Pleistocene and the Pleistocene–Holocene transition are relevant because they represent the end of a prolonged period of climatic fluctuation on multiple temporal scales followed by rapid warming. Not only did Earth's major biomes undergo extensive compositional changes during the late Quaternary and near the termination of the Pleistocene epoch, they also underwent geographically large-scale redistributions, and did so rapidly, in some cases on the scale of decades. If rapid warming during the Pleistocene–Holocene transition contributed to—or even acted as the main driver of—mass extinctions, such a scenario would seem to suggest that contemporary climate change has a similar capacity to precipitate species losses.

The Holocene is the Earth's most recent interglacial, which began approximately 11,500 years ago. Environmental change across this interval and the preceding Late Glacial, driven by factors such as orbital forcing and solar variability, can be reconstructed from archives with annually-deposited layers or annual growth layers and through the use of empirical and physical models. The early Holocene climatic optimum was an interval of warmer climate than the present day, and was followed by orbitally-related cooling which began to occur in the last 4,000–3,000 years ago. Over the last c.1200 years, three distinct climate phases are apparent in palaeo-records: the Medieval Warm Period (Ad 800–1300), the Little Ice Age (14th–16th century Ad to Ad 1850), and recent warming since AD 1850. Anthropogenic influence on global ecosystems has increased steadily since the Late Glacial, culminating in a modern-day system for which few analogues for past environments now exist.

The Bantu Expansion, the foremost linguistic, cultural, and demographic event in Late Holocene Africa, has sparked a fervent interdisciplinary debate, especially regarding its driving forces. As is often the case with hotly debated issues, certain ‘factoids’ bearing little relation to factual evidence emerge. Two such factoids are that (1) the Bantu Expansion would have been a single migratory macro-event and (2) it would have been driven by agriculture. These two widely held beliefs are critically assessed here. Regarding (1), the chapter argues that the Bantu Expansion did involve the actual migration of Bantu speakers but that backward and forward migration occurred after the initial spread and that Bantu languages also expanded through adoption by autochthonous hunter-gatherers. As for (2), the chapter argues that the earliest Bantu speakers had their own archeologically visible culture, but they were not farmers. Therefore, the Bantu Expansion is not a textbook example of a farming/language dispersal.

This chapter proposes that the field of evolutionary psychology must take seriously the notion that evolution has accelerated during the Holocene. This rapid recent evolution might call into question three foundational assumptions of evolutionary psychology: that the most important environment of evolutionary adaptedness (EEA) for explaining individual differences resides in the Pleistocene; that evolutionary equilibrium models such as balancing selection are the most relevant theories for explaining heritable variation in personality, cognitive, and mental health traits; and the degree to which psychic unity or species-typicality characterizes human psychology.

The beaver meadow is quiet in January. For many plants and animals, winter is a season of subdued activity, or of waiting. North St. Vrain Creek remains open along the main channel, the water flowing clear but tinted brown as pine bark between snowy banks. Densely growing thickets of willow closely line the banks. Each stem starts pale brown near the ground, then grades upward to shades of maroon or yellowish orange at the branch tips. In a bird’s-eye view, these startling colors make the meadow stand out distinctly from the dark green conifers that define the edges of the meadow. Spruce and fir trees grow sharply pointed as arrows; pines present a slightly more rounded outline. Snow falls silently in thick flakes from the low, gray sky. The upper edges of the valley walls fade into snow and clouds. The sun appears briefly as a small, pale spotlight behind the clouds to the south. Snow mounds on the patches of ice in the shallow channel. The water flowing beneath creates flickers through the translucent ice like a winter fire of subdued colors and no heat. Tussocks form humps of straw-colored grass above the dark, frozen soil. Rabbit tracks line the snowy bank, sets of four paw marks with a large gap between each set. Something small crossed the bank, leaping one to two feet at a bound, two paws with slight drag marks behind them. In places the powdery snow has drifted deeply, but mostly it is shallow over a frozen crust. Beaver-gnawed sticks and stumps poke up through the snow. A large flood came through four months ago, in mid-September, washing out dams that the beavers have not yet rebuilt. Chunks of wood deposited among the willow stems by the floodwaters stand far above the January flow of the creek. A dipper fishes the creek, wading rather than swimming, at home in the cold water. The slate-gray bird is the only visible animal, busily probing the bed with its short bill, then pausing to stand and bob up and down.

This chapter presents the osteobiography of a man who lived in predynastic Egypt, between 3200 B.C. and 2000 B.C.. One of only a few Neolithic skeletons representing the early Neolithic use of this large oasis, the bones and teeth present many clues about the mobile herders and foragers and the early stages of agriculture in the Western Desert of Egypt.

This chapter presents an overview of the archaeological record of three sites occupied during the Deccan Chalcolithic period (2200–700 B.C.) in India. It describes archaeological investigations at Nevasa, Daimabad, and Inamgaon, with particular attention to evidence for subsistence practices and mortuary treatment. The chapter also focuses specifically on evidence for culture change through time at Inamgaon, the only Deccan Chalcolithic site to yield an archaeological record and human skeletal material from the Late Jorwe phase, when most other sites had already been abandoned. The apparent success of adaptive diversity as a strategy for dealing with semi-arid monsoon climate uncertainty during the Early Jorwe phase is contrasted with the severe reductions in subsistence activity, shifts in species preferences, and evidence for culture change in the Late Jorwe phase.

As we wrote the first draft of this chapter (during early summer 2007), the potential dangers of ‘global warming’ had moved up the news agenda to a point where most major politicians were starting to take the problem seriously. Our opening quotation comes from a book published in early 2006, which seemed to coincide with the growth of this wider concern with global warming. Lovelock was not alone in trying to raise awareness of the problem; around the same time another book on climate change by the zoologist and palaeontologist Tim Flannery also attracted global attention to this issue, as did the lecture tours (and Oscar-winning film) of Al Gore—the former US presidential candidate and campaigner on the dangers of climate change. Indeed, in his role as a climate campaigner Gore won a share in the 2007 Nobel Peace Prize. It is possible that future historians will see the period 2005–2007 as the start of a crucial wider engagement with these problems. Things may not be as bad as James Lovelock suggests—in his book he deliberately emphasized the most worrying scenarios coming from computer models, and other evidence, in an attempt to draw attention to the critical nature of the problem. However, all these worst case scenarios were drawn from within the range of results that most climate scientists believed could plausibly happen—not extreme cases with little current evidence to support them. That one of the major environmental scientists of the second half of the twentieth century could write such prose as science—rather than science fiction—is clearly a case for concern about future climate change. It also raises another important question, relating to the history of human influence on our planet: when in our history did we start to have major environmental impacts on Earth as a whole? This is clearly an important issue from a historical perspective, but the answers may also have implications for some of our attempts to rectify the damage. Our discussion of this question comes with various caveats. Many of the arguments we consider in this chapter are still the subject of academic disagreement.

Time is running short! When the Intergovernmental Panel on Climate Change (IPCC) published its first scientific report in 1990 on the possibility of humancaused global warming, the atmospheric concentration of carbon dioxide (CO2 ) was 354 ppm. When I began writing this book about four years ago, the concentration of CO2 was 387 ppm. It is now 397 ppm and rising. In spite of Kyoto, in spite of Copenhagen and Cancun, atmospheric CO2 continues its inexorable upward path. And the earth continues to warm. The United States and the world are not yet serious about changing policies to stop this spiral. Too many politicians and others have their heads buried in the sand and refuse to acknowledge the continuing deluge of data showing that the world is indeed warming. 2010 was the warmest year—and the decade from 2000 to 2010 was the warmest decade—for at least the last 100,000 years. A serious debate is ongoing among geologists to decide if the earth has formally passed out of the Holocene epoch of the last 12,000 years into the Anthropocene epoch, in which 7 billion humans are the primary factor driving climate. Sea levels continue to rise, the oceans are acidifying, glaciers and ice sheets continue to melt, the Arctic will likely be ice-free during the summer sometime this century, and weather extremes have become commonplace around the earth. Plant and animal species are migrating to higher latitudes at 17 kilometers per decade on average, and alpine species are moving to higher altitudes at 11 meters every decade. Changes like this have occurred in the past, but over time spans of thousands to tens of thousands of years, giving species time to adapt. There are those who argue that species have always had to adapt to a changing climate or die and therefore they will handle the current changes. While there is some truth to that, it ignores the fact that many species are already under great pressure from the impact of humans on habitat.

We, the teeming billions of people on earth, are changing the earth’s climate at an unprecedented rate because we are spewing out greenhouse gases and are heading to a disaster, say most climate scientists. Not so, say the skeptics. We are just experiencing normal variations in earth’s climate and we should all take a big breath, settle down, and worry about something else. Which is it? A national debate has raged for the last several decades about whether anthropogenic (man-made) sources of carbon dioxide (CO2 ) and other so-called “greenhouse gases“ (primarily methane and nitrous oxide) are causing the world to heat up. This phenomenon is usually called “global warming,” but it is more appropriate to call it “global climate change,” since it is not simply an increase in global temperatures but rather more complex changes to the overall climate. Al Gore is a prominent spokesman for the theory that humans are causing an increase in greenhouse gases leading to global climate change. His movie and book, An Inconvenient Truth, gave the message widespread awareness and resulted in a Nobel Peace Prize for him in 2008. However, the message also led to widespread criticism. On the one hand are a few scientists and a large segment of the general American public who believe that there is no connection between increased CO2 in the atmosphere and global climate change, or if there is, it is too expensive to do anything about it, anyway. On the other hand is an overwhelming consensus of climate scientists who have produced enormous numbers of research papers demonstrating that increased CO2 is changing the earth’s climate. The scientific consensus is expressed most clearly in the Fourth Assessment Report in 2007 by the United Nations–sponsored Intergovernmental Panel on Climate Change (IPCC), the fourth in a series of reports since 1990. The IPCC began as a group of scientists meeting in Geneva in November 1988 to discuss global climate issues under the auspices of the World Meteorological Organization and the United Nations Environment Program.

Friedrich Wöhler was referring to the field of organic chemistry during the early 1800s when he wrote the above but his comments would not be out of place in the context of embarking upon a global study of past and present human relationships with tropical forests. Dense vegetation, difficulty of navigation, issues of preservation, political and health concerns, poisonous plants, animals, and insects, and the prospect of carrying out sampling or excavation in high humidity have all meant that our knowledge of human history and prehistory in these environments is under-developed relative to temperate, arid, or even polar habitats. There have been theoretical questions as to what kind of human activity one would even expect to find in tropical forest environments, which seem hostile to human foraging (Hart and Hart, 1986; Bailey et al., 1989) let alone thriving agricultural or urban settlements (Meggers, 1971, 1977, 1987). This has, until relatively recently, left the state of archaeological tropical forest research in a similar position to popular conceptions of these environments—untouched, primeval wilderness. Public ideas of an archaeologist investigating a tropical forest are probably synonymous with someone in a shabby-looking leather hat being chased, if not by a large stone boulder then by a group of Indigenous people with blowpipes, as they wade through dense undergrowth and vines while clutching a golden discovery that has been lost to the western world for thousands of years (Spielberg, 1981). The more recent development of the best-selling Uncharted video game series has done little to change these ideas amongst the next generation of media consumers, with players taking on the role of Francis Drake’s mythical ancestor in search of long lost treasure, frequently hidden within caves and ruins surrounded by vines and dense canopies (Naughty Dog et al., 2016). The idea of treasure hidden within tropical forest is also not a modern conception. The long-term myth of El Dorado, a city covered in gold, fuelled exploration of the tropical forests of South America by renowned individuals, including Sir Walter Raleigh, from the sixteenth to the nineteenth centuries (Nicholl, 1995).

In geological time, the human life span is almost immeasurably brief. The seventeenth-century archbishop James Ussher famously calculated from biblical events that Earth was formed in 4004 BCE; scientists now estimate that the planet is 4.6 billion years old, and that the six millennia since the apocryphal Creation have probably contributed less than 10 millimeters of sediment to the geological record. Geological eras are unfathomable by ordinarily temporal measurements, such as the daily spin of the planet or its annual orbit, leading some scientists to adopt the galactic year—the 250 million terrestrial years it takes our solar system to rotate around the center of the galaxy—as a standard time unit. On that scale, Homo sapiens has been around for less than a week. Yet as the technology to study the planet has improved, so too has the technology to alter it. Earth increasingly disproportionately bears our imprint, as if geological time were being accelerated to the beat of our biological clock, with the consequence that the planet seems increasingly mortal, its legacy and ours entangled. In geological terms we are in the Holocene epoch—a designation formulated from Greek roots meaning “wholly recent,” officially adopted at the 1885 International Geological Congress—and have been in the Holocene for the past ten thousand years. The question, given all that we’ve done to the planet, is whether the label remains valid, or whether we’ve now buried the stratum of our Neolithic ancestors beneath our own rubbish. The atmospheric chemist Paul Crutzen was the first to effectively challenge the conventional geological thinking. In a 2003 interview with New Scientist he recollected the circumstances: “This happened at a meeting three years ago. Someone said something about the Holocene, the geological era covering the period since the end of the last ice age. I suddenly thought this was wrong. In the past 200 years, humans have become a major geological force on the planet. So I said, no, we are not in the Holocene any more: we are in the Anthropocene. I just made up the word on the spur of the moment.

This book addresses the question of how the removal of whales in various fisheries influenced the workings of modern oceans. Despite the recent and dramatic nature of these events, their consequences are both controversial and poorly documented. This chapter presents a comparative view of other systems in which food web reorganization has apparently followed anthropogenic disturbances to key vertebrates. It argues that prehistoric, historic, and present-day reductions in some vertebrate populations may have been initially triggered by human action. These reductions subsequently distorted ecological dynamics, leading to ecosystem simplification or decay. The chapter turns to deep history in an effort to examine terrestrial vertebrate extinctions in the late Pleistocene and Holocene. It also discusses historic and contemporary examples of strong species interactions and ecosystem decay, starting on land and moving to coastal seas.