Book Review

Anthony Penna, The Human Footprint: A Global Environmental History. Sussex, United Kingdom: Wiley-Blackwell, 2010. 354 pages. $39.95.

     In the first two chapters, Penna notes that as the continents collided, mountain building caused climate changes which ultimately created an environment conducive for human evolution and migration. In Europe, for example, the shifting of tectonic plates 5.5 million years ago and the subsequent filling of the Mediterranean Sea turned "a dry, arid, dusty and inhospitable region" into a land that would "one day become a center for civilization" (p. 29). The intimate connection between tectonic activity, climate change, and human evolution continues in chapter two. Penna explains that frequent and predictable cycles of global cooling and warming over the past 740,000 years allowed for either the shrinking or expanding of the savannas and forests which then "became the cradles of evolution and either grew or contracted because of changes in climate" (p. 38). Penna persuasively argues that rapid climate change "quickened the pace of evolution" as humans mentally and physically adapted to new conditions.

     Climate change, again, was responsible for the great agrarian transformation at the end of the Pleistocene era (2.5 million to 12,000 BP) and the beginning of the present Holocene era. In chapter three, the warming trend at the end of the Pleistocene caused glaciers to recede as humans settled in rich, fertile lands and cultivated and domesticated wild plants. "Global rifting, climatic disruptions, and environmental changes," claims Penna, "led to rapid human economic and cultural adaptations" (p. 60). Chapter four tackles population and Penna presents evidence that the current rapid population increase will gradually stabilize at just under nine billion in 2050 and then "enter an extended period of depopulation" (p. 85). He cites new census figures from the United Nations that calculates fertility trends today at 1.85 children per household rather than 2.1—a number well below the population replacement level. In a section on diet, Penna corroborates the typical scholarly arguments that the transition from hunting and gathering to agriculture generally (with a few exceptions) led to increased malnutrition and decreased life expectancy. Population, nonetheless, steadily rose as a result of the agrarian transition. He answers the familiar question "why would a population incur a serious health risk by making the transition from hunting to farming" by again returning to climate as the cause (p. 95). He states that micro-parasites increased due to a warming atmosphere, perhaps forcing humans to increase their reproductive rates though intensive crop production and animal domestication in the face of rising diseases.

     Urbanization is the theme of chapter five. Here Penna relates the devastating environmental toll caused by the emergence of early cities including waste, disease, deforestation, and irrigation. He wisely leaves an analysis of the industrial city for a later chapter. Penna attempts to treat mining and manufacturing (chapter six) and industry (chapter seven) as continuities rather than historical departures. Yet he seemingly contradicts himself when he labels Britain's economic transformation in the nineteenth century as "an important breakthrough in the relationship between humans and the natural world" (p. 174). Like world historians before him, Penna also questions why China did not industrialize as rapidly as Europe. Yet rather than highlight coal and colonies (Pomeranz, 2000), he seems to favor an article from Jack Goldstone (1996) arguing that China's "long history of restricted mobility for women and a traditional household economy in spinning and weaving cotton served as an insurmountable barrier to technological innovation and a centralized factory system" (p. 177). As factory workers, western women provided the necessary energy to fuel industrialization. This section begged for a more thorough review of the current scholarship.

     In chapter eight Penna stresses that consumption was also an evolutionary development much like agriculture, manufacturing, and industry. By emphasizing the growing separation of producers of food from the consumers, which began during the era of long-distance trade 1460–1600, humans lost their concept of an "ecological footprint" as consumers became "detached from the reality of the life and death of the biological organisms that they consumed" (p. 213). Energy is the topic of chapter nine as Penna traces the move from wind and water energy to fossil fuels (coal and oil) and nuclear energy. He particularly emphasizes the stress that the automobile places on the natural world, citing oil spills and toxic emissions. He also makes a compelling case for renewable wind and solar power. The book ends with "A Warming Climate," and nowhere have I ever read a more helpful explanation as to both the causes and consequences of the current state of climate change. The ending was truly a triumph as it carefully details how three basic causes for climate change—the ocean current, fossil fuel emissions, and solar energy—might well be the harbingers of an impending climate disaster.

     This is an important book for instructors who teach world environmental history as it provides a valuable synthesis of information on topics such as climate, geology, and the industrial revolution. I will use this book to supplement my lecture material in my freshman course, "World History and the Environment." However, I would not assign this book as a text in the course because it assumes readers are already fluent in world historical chronology and major events. It might, however, be suitable for an undergraduate upper-division or graduate course on global environmental history.

     Although the information in the book was instructive, it nonetheless suffered from several problems. First, I question the author's use of BP (Before Present, or the number of radio carbon years before 1950) in several instances. BP is the time scale used by archeologists, geologists, and scientists, but not historians. While it might have been acceptable to use BP in his treatment of deep geological time in the first chapters, it nonetheless became extremely vexing to learn that China's Han emperor's reigned from 2206 BP–120 CE (p. 161) or that Sargon of Akkad lived from 4334–4279 BP (p. 120) or Hammurabi from 3792–3750 BP (p. 119). Also distracting throughout the book was the author's improper and awkward use of quotations. Quotes frequently stood alone without an introduction (dropped quotes), and Penna ended many paragraphs with quotes without offering any analysis of the citation. Moreover, there was some misinformation in several chapters: for example, the bubonic plague that followed the great European famine occurred in the 14^th century, not the year 1400 CE (p. 285), and Finns don't actually drink 11.5 cups of coffee a day, rather Finland imports around 11.5 kg of coffee per year per capita—I checked Penna's internet source (p. 232). And finally, although the sources in this text are adequate, they were not exhaustive as say, J. Donald Hughes' An Environmental History of the World or Clive Ponting's A New Green History of the World.

     Despite these shortcomings, The Human Footprint is a welcome addition to the field of world environmental history. While not groundbreaking, I recommend this valuable survey to all who teach in the field.

Mary Jane Maxwell is Assistant Professor of History and Religious Studies at Green Mountain College. She can be reached at maxwellmj@greenmtn.edu.