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Return to the Sea portrays the life and evolutionary times of marine mammals from giant whales and sea cows that originated fifty-five million years ago and walked on land to deep-diving elephant seals and clam-eating walruses of modern times. Some animals, like the hippo-sized herbivorous desmostylians and aquatic sloths, were evolutionary experiments that did not survive. This fascinating account of the origin of various marine mammal lineages, written for the nonspecialist, is set against a backdrop of geologic time, changing climates and geography. The thread of evolution runs through the book and helps us to understand the present-day diversity of marine mammals and their responses to environmental challenges. The story of the evolution of these fascinating animals, their life and habits, offers a valuable perspective and, in some cases, lessons for the future. Berta also informs readers about current controversies in the field of marine mammalogy, presenting a balanced view based on careful evaluation and interpretation of the evidence. She explores patterns of change taking place today—conservation issues such as changing food webs and predator-prey relationships, habitat degradation, global warming, and the effects of humans on marine mammal communities. The future of marine mammals depends on each of us, scientists as well as the informed public, working together to avoid crises before they develop or to appropriately manage those that arise.

How can we bring together the study of genes, embryos, and fossils? This is a critical synthesis of the study of individual development in fossils. It brings together an up-to-date review of concepts from comparative anatomy, ecology, and developmental genetics, and examples of different kinds of animals from diverse geological epochs and geographic areas. Can fossil embryos demonstrate evolutionary changes in reproductive modes? How have changes in ocean chemistry in the past affected the development of marine organisms? What can the microstructure of fossil bone and teeth reveal about maturation time, longevity, and changes in growth phases? This book addresses these and other issues, and documents with numerous examples and illustrations how fossils provide evidence not only of adult anatomy, but also of the life history of individuals at different growth stages. The central topic of biology today—the transformations occurring during the life of an organism and the mechanisms behind them—is addressed in an integrative manner for extinct animals.

Molecular studies have revealed highly ordered geographic patterns in plant and animal groups, and this book discusses examples from the tropics. During evolution, phases of community immobilism that lead to allopatric differentiation alternate with phases of mobilism that lead to range expansion and overlap of taxa. Both phases are caused by geological and climatic factors rather than group-specific factors such as ecology or means of dispersal. In primates, the endemism of high-level taxa in tropical America (New World monkeys) and Madagascar (lemurs) is attributed to Gondwana breakup, while the extensive overlap of clades in South America, Africa, and Asia may have been caused by range expansion during Cretaceous marine transgressions. In the central Pacific, former high islands of the Cretaceous (now seamounts and atolls) may have been important source areas for the biotas of the current islands. The integration of earth history, biogeography, and ecology proposed here leads to an alternative view of evolution, in which groups are much older than suggested by the fossil record and fossil-calibrated molecular clocks. The book concludes with a critique of adaptation by selection, based on biogeography and recent work in genetics.

Cladistics, or phylogenetic systematics — an approach to discovering, unraveling, and testing hypotheses of evolutionary history — took hold during a turbulent and acrimonious time in the history of systematics. During this period — the 1960s and 1970s — much of the foundation of modern systematic methodology was established as cladistic approaches became widely accepted. Virtually complete by the end of the 1980s, the wide perception has been that little has changed. This volume vividly illustrates that cladistic methodologies have continued to be developed, improved upon, and effectively used in ever widening analytically imaginative ways.

This volume is a comprehensive review of the African mammalian fossil record over the past 65 million years. The book includes current taxonomic and systematic revisions of all African mammal taxa, detailed compilations of fossil site occurrences, and a wealth of information regarding paleobiology, phylogeny, and biogeography. Primates, including hominins, are particularly well covered. The discussion addresses the systematics of endemic African mammals, factors relating to species richness, and a summary of isotopic information. The work also provides contextual information about Cenozoic African tectonics, chronostratigraphy of sites, paleobotany, and global and regional climate change. Updating our understanding of this important material with the wealth of research from the past three decades, this volume is an essential resource for anyone interested in the evolutionary history of Africa and the diversification of its mammals.

More than three hundred million years ago—a relatively recent date in the two billion years since life first appeared—vertebrate animals first ventured onto land. This illustrated book describes how some finned vertebrates acquired limbs, giving rise to more than 25,000 extant tetrapod species. The author uses paleontological, geological, physiological, and comparative anatomical data to describe this monumental event. He summarizes key concepts of modern paleontological research, including biological nomenclature, paleontological and molecular dating, and the methods used to infer phylogeny and character evolution. Along with a discussion of the evolutionary pressures that may have led vertebrates onto dry land, the book also shows how extant vertebrates yield clues about the conquest of land and how scientists uncover evolutionary history.

To unravel the complex shared history of the Earth and its life forms, biogeographers analyze patterns of biodiversity, species distribution, and geological history. So far, the field of biogeography has been fragmented into divergent systematic and evolutionary approaches, with no overarching or unifying research theme or method. In this text, the authors address this discord and outline comparative tools to unify biogeography. Rooted in phylogenetic systematics, this comparative biogeographic approach offers a comprehensive empirical framework for discovering and deciphering the patterns and processes of the distribution of life on Earth. The authors cover biogeography from its fundamental ideas to the most effective ways to implement them. Real-life examples illustrate concepts and problems, including the first comparative biogeographical analysis of the Indo-West Pacific, an introduction to biogeographical concepts rooted in the earth sciences, and the integration of phylogeny, evolution, and earth history.

The sequencing of the human genome involved thousands of scientists but used relatively few tools. Today, obtaining sequences is simpler, but aligning them—making sure that sequences from one source are properly compared to those from others—remains a complicated but underappreciated aspect of comparative molecular biology. This book, whic focuses on this crucial step in analyzing sequence data, is about the practice of alignment, the procedures by which alignments are established, and, more importantly, how the outcomes of any alignment algorithm should be interpreted. It covers molecular causes, computational advances, approaches for assessing alignment quality, and philosophical underpinnings of the algorithms themselves.

More than two centuries ago, William Paley introduced his famous metaphor of the universe as a watch made by the Creator. For him, the exquisite structure of the universe necessitated a designer. Today, some 150 years since Darwin's On the Origin of Species was published, the argument of design is seeing a revival. This work tells how Darwin left the door open for this revival—and at the same time argues for a new conceptual framework that avoids the problematic teleology inherent in Darwin's formulation of natural selection. In a wide-ranging discussion of the historical and philosophical dimensions of evolutionary theory from the ancient Greeks to today, the author argues that we should look to the principle of the conditions for existence, first formulated before On the Origin of Species by the French paleontologist Georges Cuvier, to clarify the relation of adaptation to evolution. He suggests that Cuvier's principle can help resolve persistent issues in evolutionary biology, including the proper definition of natural selection, the distinction between natural selection and genetic drift, and the meaning of genetic load. Moreover, the author shows how this principle can help unite diverse areas of biology, ranging from quantitative genetics and the theory of the levels of selection to evo-devo, ecology, physiology, and conservation biology.

Adaptive radiation—which results when a single ancestral species gives rise to many descendants, each adapted to a different part of the environment—is possibly the single most important source of biological diversity in the living world. One of the best-studied examples involves Caribbean Anolis lizards. With about 400 species, Anolis has played an important role in the development of ecological theory and has become a model system exemplifying the integration of ecological, evolutionary, and behavioral studies to understand evolutionary diversification. This major work, written by one of the best-known investigators of Anolis, reviews and synthesizes an immense literature. The author illustrates how different scientific approaches to the questions of adaptation and diversification can be integrated, and examines evolutionary and ecological questions of interest to a broad range of biologists.