The invasion of land by ocean-dwelling plants and animals was one of the most revolutionary events in the evolution of life on Earth, yet the animal invasion almost failed—twice—because of the twin mass extinctions of the Late Devonian Epoch. Some 359 to 375 million years ago, these catastrophic events dealt our ancestors a blow that almost drove them back into the sea. If those extinctions had been just a bit more severe, spiders and insects—instead of vertebrates—might have become the ecologically dominant forms of animal life on land. This book examines the profound evolutionary consequences of the Late Devonian extinctions and the various theories proposed to explain their occurrence. Only one group of four-limbed vertebrates exists on Earth, while other tetrapod-like fishes are extinct. This gap is why the idea of "fish with feet" seems so peculiar to us, yet such animals were once a vital part of our world, and if the Devonian extinctions had not happened, members of these species, like the famous Acanthostega and Ichthyostega, might have continued to live in our rivers and lakes. Synthesizing decades of research and including a wealth of new discoveries, this accessible, comprehensive text explores the causes of the Devonian extinctions, the reasons vertebrates were so severely affected, and the potential evolution of the modern world if the extinctions had never taken place.

The Devonian was a peculiar period, characterized by simplified plate tectonic configurations, climatic overheating and widely flooded continents. The bloom of fishes and ammonoids, extensive reef complexes, and the conquest of land indicate major biosphere innovations, punctuated by many global events, including two of the biggest mass extinctions. The Devonian was the first system for which subdivisions were formally defined. This was achieved by significant advances in pelagic biostratigraphy. The chronostratigraphic framework and interdisciplinary techniques allow us to correlate intervals or sudden events across facies boundaries, in order to reconstruct the sedimentary and evolutionary history of the system with highest precision. This volume honors the lifetime stratigraphic achievements of Michael Robert House (1930-2002). Based on case studies from Europe, North Africa and North America, it shows how the combination of biostratigraphy, chemostratigraphy, magnetostratigraphy, sequence stratigraphy and event stratigraphy can contribute to a much deeper understanding of both regional and global environmental change.

The Late Devonian and Permian-Triassic intervals are among the most dynamic episodes of Earth history, marked by large secular changes in continental ecosystems, dramatic fluctuations in ocean oxygenation, major phases of biotic turnover, volcanism, bolide impact events, and rapid fluctuations in stable isotope systems and sea level. This volume highlights contributions from a broad range of geological sub-disciplines currently striving to understand these critical intervals of geologically rapid, global-scale changes.* Provides updated, current models for the mid-Late Devonian and Permian-Triassic mass extinction episodes* Highlights several new analytical approaches for developing quantitative datasets* Takes an integrated approach presenting datasets from a broad range of sub-disciplines

"Arguably the best work to date in the history of geology."—David R. Oldroyd, Science "After a superficial first glance, most readers of good will and broad knowledge might dismiss [this book] as being too much about too little. They would be making one of the biggest mistakes in their intellectual lives. . . . [It] could become one of our century's key documents in understanding science and its history."—Stephen Jay Gould, New York Review of Books "Surely one of the most important studies in the history of science of recent years, and arguably the best work to date in the history of geology."—David R. Oldroyd, Science

The rapid evolution of terrestrial ecosystems in the Devonian Period combined with climate change and many global events had a pronounced influence on sedimentation and biodiversity in various terrestrial and marine settings. This volume presents a number of case studies which cover the following topics land-sea transitional settings, the role of ecological-evolutionary subunits, the diversity and palaeoecology of reef building organisms and microfloras with respect to sedimentary processes and global events.