Extinctions In Near Time

"Near time" -an interval that spans the last 100,000 years or so of earth history-qualifies as a remarkable period for many reasons. From an anthropocentric point of view, the out standing feature of near time is the fact that the evolution, cultural diversification, and glob al spread of Homo sapiens have all occurred within it. From a wider biological perspective, however, the hallmark of near time is better conceived of as being one of enduring, repeat ed loss. The point is important. Despite the sense of uniqueness implicit in phrases like "the biodiversity crisis," meant to convey the notion that the present bout of extinctions is by far the worst endured in recent times, substantial losses have occurred throughout near time. In the majority of cases, these losses occurred when, and only when, people began to ex pand across areas that had never before experienced their presence. Although the explana tion for these correlations in time and space may seem obvious, it is one thing to rhetori cally observe that there is a connection between humans and recent extinctions, and quite another to demonstrate it scientifically. How should this be done? Traditionally, the study of past extinctions has fallen largely to researchers steeped in such disciplines as paleontology, systematics, and paleoecology. The evaluation of future losses, by contrast, has lain almost exclusively within the domain of conservation biolo gists. Now, more than ever, there is opportunity for overlap and sharing of information.

ONE OF THE NEW YORK TIMES BOOK REVIEW'S 10 BEST BOOKS OF THE YEAR A major book about the future of the world, blending intellectual and natural history and field reporting into a powerful account of the mass extinction unfolding before our eyes Over the last half a billion years, there have been five mass extinctions, when the diversity of life on earth suddenly and dramatically contracted. Scientists around the world are currently monitoring the sixth extinction, predicted to be the most devastating extinction event since the asteroid impact that wiped out the dinosaurs. This time around, the cataclysm is us. In The Sixth Extinction, two-time winner of the National Magazine Award and New Yorker writer Elizabeth Kolbert draws on the work of scores of researchers in half a dozen disciplines, accompanying many of them into the field: geologists who study deep ocean cores, botanists who follow the tree line as it climbs up the Andes, marine biologists who dive off the Great Barrier Reef. She introduces us to a dozen species, some already gone, others facing extinction, including the Panamian golden frog, staghorn coral, the great auk, and the Sumatran rhino. Through these stories, Kolbert provides a moving account of the disappearances occurring all around us and traces the evolution of extinction as concept, from its first articulation by Georges Cuvier in revolutionary Paris up through the present day. The sixth extinction is likely to be mankind's most lasting legacy; as Kolbert observes, it compels us to rethink the fundamental question of what it means to be human.

“The focus is the most severe mass extinction known in earth’s history. The science on which the book is based is up-to-date, thorough, and balanced. Highly recommended.” —Choice Today it is common knowledge that the dinosaurs were wiped out by a meteorite impact 65 million years ago that killed half of all species then living. It is far less widely understood that a much greater catastrophe took place at the end of the Permian period 251 million years ago: at least ninety percent of life on earth was destroyed. When Life Nearly Died documents not only what happened during this gigantic mass extinction but also the recent renewal of the idea of catastrophism: the theory that changes in the earth’s crust were brought about suddenly in the past by phenomena that cannot be observed today. Was the end-Permian event caused by the impact of a huge meteorite or comet, or by prolonged volcanic eruption in Siberia? The evidence has been accumulating, and Michael J. Benton gives his verdict at the end of the volume. The new edition brings the study of the greatest mass extinction of all time thoroughly up-to-date. In the twelve years since the book was originally published, hundreds of geologists and paleontologists have been investigating all aspects of how life could be driven to the brink of annihilation, and especially how life recovered afterwards, providing the foundations of modern ecosystems.

The volume contains summaries of facts, theories, and unsolved problems pertaining to the unexplained extinction of dozens of genera of mostly large terrestrial mammals, which occurred ca. 13,000 calendar years ago in North America and about 1,000 years later in South America. Another equally mysterious wave of extinctions affected large Caribbean islands around 5,000 years ago. The coupling of these extinctions with the earliest appearance of human beings has led to the suggestion that foraging humans are to blame, although major climatic shifts were also taking place in the Americas during some of the extinctions. The last published volume with similar (but not identical) themes -- Extinctions in Near Time -- appeared in 1999; since then a great deal of innovative, exciting new research has been done but has not yet been compiled and summarized. Different chapters in this volume provide in-depth resumés of the chronology of the extinctions in North and South America, the possible insights into animal ecology provided by studies of stable isotopes and anatomical/physiological characteristics such as growth increments in mammoth and mastodont tusks, the clues from taphonomic research about large-mammal biology, the applications of dating methods to the extinctions debate, and archeological controversies concerning human hunting of large mammals.

Some 250 million years ago, the earth suffered the greatest biological crisis in its history. Around 95 percent of all living species died out—a global catastrophe far greater than the dinosaurs' demise 185 million years later. How this happened remains a mystery. But there are many competing theories. Some blame huge volcanic eruptions that covered an area as large as the continental United States; others argue for sudden changes in ocean levels and chemistry, including burps of methane gas; and still others cite the impact of an extraterrestrial object, similar to what caused the dinosaurs' extinction. Extinction is a paleontological mystery story. Here, the world's foremost authority on the subject provides a fascinating overview of the evidence for and against a whole host of hypotheses concerning this cataclysmic event that unfolded at the end of the Permian. After setting the scene, Erwin introduces the suite of possible perpetrators and the types of evidence paleontologists seek. He then unveils the actual evidence--moving from China, where much of the best evidence is found; to a look at extinction in the oceans; to the extraordinary fossil animals of the Karoo Desert of South Africa. Erwin reviews the evidence for each of the hypotheses before presenting his own view of what happened. Although full recovery took tens of millions of years, this most massive of mass extinctions was a powerful creative force, setting the stage for the development of the world as we know it today. In a new preface, Douglas Erwin assesses developments in the field since the book's initial publication.

This makes a detailed consideration of these extinctions a useful system for investigating the impacts of human activity over time.

Following the trails of Hawai‘i’s snails to explore the simultaneously biological and cultural significance of extinction. In this time of extinctions, the humble snail rarely gets a mention. And yet snails are disappearing faster than any other species. In A World in a Shell, Thom van Dooren offers a collection of snail stories from Hawai‘i—once home to more than 750 species of land snails, almost two-thirds of which are now gone. Following snail trails through forests, laboratories, museums, and even a military training facility, and meeting with scientists and Native Hawaiians, van Dooren explores ongoing processes of ecological and cultural loss as they are woven through with possibilities for hope, care, mourning, and resilience. Van Dooren recounts the fascinating history of snail decline in the Hawaiian Islands: from deforestation for agriculture, timber, and more, through the nineteenth century shell collecting mania of missionary settlers, and on to the contemporary impacts of introduced predators. Along the way he asks how both snail loss and conservation efforts have been tangled up with larger processes of colonization, militarization, and globalization. These snail stories provide a potent window into ongoing global process of environmental and cultural change, including the largely unnoticed disappearance of countless snails, insects, and other less charismatic species. Ultimately, van Dooren seeks to cultivate a sense of wonder and appreciation for our damaged planet, revealing the world of possibilities and relationships that lies coiled within a snail’s shell.