This is a book about the dramatic periods in the Earth's history called mass extinctions - short periods (by geological standards) when life nearly died out on Earth. The most famous is the mass extinction that happened about 65 million years ago, and that caused the death of the dinosaurs. But that was not the worst mass extinction: that honour goes to the extinction at the end of the Permian Period, about 250 million years ago, when over 90% of life is thought to have become extinct. What caused these catastrophes? Was it the effects of a massive meteorite impact? There is evidence for such an impact about 65 million years ago. Or was it a period of massive volcanic activity? There is evidence in the rocks of huge lava flows at periods that match several of the mass extinctions. Was it something to do with climate change and sea level? Or was it a combination of some or all of these? The question has been haunting geologists for a number of years, and it forms one of the most exciting areas of research in geology today. In this book, Tony Hallam, a distinguished geologist and writer, looks at all the different theories and also what the study of mass extinctions might tell us about the future. If climate change is a key factor, we may well, as some scientists have suggested, be in a period of mass extinction of our own making.

The mechanisms of magma movement, chemical differentiation and physical development, are derived from the geochemistry of igneous rocks, and from studying exposures of deep magmatic systems that have since solidified and been uplifted and exposed at the Earth's surface. The Ferrar Magmatic System of the McMurdo Dry Valleys in Antarctica provides an unparalleled example of a complete magmatic-volcanic system exposed in unprecedented detail. This book provides a unique and usual three-dimensional detailed examination of this system, providing insight into many magmatic processes normally unobservable, in particular how basaltic magma moves upwards through the crust, how it entrains, carries and deposits loads of crystals from great depths, and how this all contributes to Earth's evolution. Providing an explanation of how magmatic systems operate and how igneous rocks form, this is an invaluable resource ideal for researchers and graduate students in magma physics, igneous petrology, volcanology, and geochemistry.

South America is home to some of the most distinctive mammals on Earth—giant armadillos, tiny anteaters, the world's largest rodent, and its smallest deer. But the continent once supported a variety of other equally intriguing mammals that have no close living relatives: armored mammals with tail clubs, saber-toothed marsupials, and even a swimming sloth. We know of the existence of these peculiar species thanks to South America's rich fossil record, which provides many glimpses of prehistoric mammals and the ecosystems in which they lived. Organized as a "walk through time" and featuring species from 15 important fossil sites, this book is the most extensive and richly illustrated volume devoted exclusively to the Cenozoic mammals of South America. The text is supported by 75 life reconstructions of extinct species in their native habitats, as well as photographs of fossil specimens and the sites highlighted in the book. An annotated bibliography is included for those interested in delving into the scientific literature.