Artiodactyls are diverse and successful hoofed mammals, represented by nearly two hundred living species of pigs, peccaries, hippos, camels, deer, sheep, cattle, giraffes, and other even-toed ungulates. In the recent years, a tremendous amount of research has been conducted on this important order. The Evolution of Artiodactyls synthesizes this research into a single volume. The authors explore a variety of topics, including molecular phylogeny of terrestrial artiodactyls phylogenetic relationships of cetaceans to terrestrial artiodactyls, and the earliest artiodactyls—Diacodexidae, Dichobunidae, Homacodontidae, Leptochoeridae, and Raoellidae.
One of the leading textbooks in its field, Bringing Fossils to Life applies paleobiological principles to the fossil record while detailing the evolutionary history of major plant and animal phyla. It incorporates current research from biology, ecology, and population genetics, bridging the gap between purely theoretical paleobiological textbooks and those that describe only invertebrate paleobiology and that emphasize cataloguing live organisms instead of dead objects. For this third edition Donald R. Prothero has revised the art and research throughout, expanding the coverage of invertebrates and adding a discussion of new methodologies and a chapter on the origin and early evolution of life.
Since the extinction of the dinosaurs, hoofed mammals have been the planet's dominant herbivores. Native to all continents except Australia and Antarctica, recent paleontological and biological discoveries have deepened understanding of their evolution. This text reveals their evolutionary history.
Hans Thewissen, a leading researcher in the field of whale paleontology and anatomy, gives a sweeping first-person account of the discoveries that brought to light the early fossil record of whales. As evidenced in the record, whales evolved from herbivorous forest-dwelling ancestors that resembled tiny deer to carnivorous monsters stalking lakes and rivers and to serpentlike denizens of the coast. Thewissen reports on his discoveries in the wilds of India and Pakistan, weaving a narrative that reveals the day-to-day adventures of fossil collection, enriching it with local flavors from South Asian culture and society. The reader senses the excitement of the digs as well as the rigors faced by scientific researchers, for whom each new insight gives rise to even more questions, and for whom at times the logistics of just staying alive may trump all science. In his search for an understanding of how modern whales live their lives, Thewissen also journeys to Japan and Alaska to study whales and wild dolphins. He finds answers to his questions about fossils by studying the anatomy of otters and porpoises and examining whale embryos under the microscope. In the book's final chapter, Thewissen argues for approaching whale evolution with the most powerful tools we have and for combining all the fields of science in pursuit of knowledge.
Mammalian morphological response to Cenozoic environmental change has long been studied. Traditionally, the appearance of hypsodonty in equids is considered an adaptation to the introduction of abrasive material to the diet (e.g. grass), and has been used as a means of signifying the opening of environments. However, the timing of the radiation of hypsodont equids conflicts with the paleobotanical appearance of grasses and, in fact, hyspodont dentition may not necessarily indicate the addition of grasses to the diet. Despite the conflict arising between dentition and timing of environmental opening, other skeletal characters can be examined for morphological adaptation to environmental opening (e.g. cursoriality). In an attempt to further explore ungulate adaptation to environment, I am evaluating the Order Artiodactyla for rate of cursorial evolution. Artiodactyla was selected because of the availability of a large number of extant and extinct specimens and the fact that these ungulates emerged and radiated during the time of environmental opening. This study represents novel research by exploring fusions and reductions in the number of distal limb elements across the entire order. Reductions and fusions are important to cursoriality because they reduce the limb0́9s distal weight and render the distal limb elements more stable, allowing for faster and more efficient locomotion across open terrain. The spread of open environments (e.g., savannas), as a result of Cenozoic environmental change, might have provided an impetus for these types of cursorial adaptations. Cenozoic environmental opening is believed to have occurred gradually, beginning as small patches of low-biomass vegetation in the Eocene, leading to short grasslands in the Oligocene, followed by the tall, modern grasslands of the Late Miocene. With this in mind, my working hypothesis that the opening of environment drives cursorial adaptation, and therefore, rates of cursoriality should be highest from the Eocene to Late Miocene. To test this, 306 artiodactyls were analyzed for 47 discrete characters in limb morphology that were indicative of cursorial adaptations and recorded in Mesquite 2.72 (build 514). I calculated the rate of limb evolution across the entire order and found that there was a very high peak throughout the Eocene, which has also been found in ungulates by a study examining metatarsal/femur ratios- a method used to determine cursoriality. In addition, the earliest artiodactyls (about 55Mya) were already showing signs of cursoriality. The evidence suggested by my results, metatarsal/femoral ratios and the morphology of the earliest artiodactyls indicate that artiodactyls were evolving cursorial adaptations early on in their evolutionary history. In addition to the high rate of the Eocene, I found a slight increase of rate during the Late Oligocene. This increase in rate coincides with a dramatic increase in open habitat phytolith assemblages from the Great Plains of North America. This may indicate that artiodactyl cursoriality rate was increasing simultaneous to North American environmental opening. My hypothesis that the opening of environments drives cursorial adaptation is supported by the second, smaller peak of the Late Oligocene, but more research is needed to explore this drastically high rate of cursorial adaptation during the Eocene, which was considered to be a time of closed, widespread forests with few pockets of low-biomass vegetation.
A group of special interest to mammalogists, taxonomists, and systemicists, ungulates have proven difficult to classify. This comprehensive review of the taxonomic relationships of artiodactyls and perissodactyls brings forth new evidence in order to propose a theory of ungulate taxonomy. With this straightforward volume, Colin Groves and the late Peter Grubb cut through previous assumptions to define ungulate genera, species, and subspecies. The species-by-species accounts incorporate new molecular, cytogenetic, and morphological data, as well as the authors’ own observations and measurements. The authors include references and supporting arguments for new classifications. A starting point for further research, this book is sure to be discussed and hotly debated in the mammalogical community. A well-reasoned synthesis, Ungulate Taxonomy will be a defining volume for years to come.
Research in whale origins is now in an explosive phase, with a cascade of discoveries adding to our understanding of the evolutionary pattern and a suite of new techniques being applied to address new questions. The objective of this volume is to provide a snapshot of this explosion. The volume paints the scene with a broad brush. Taken together the chapters clearly indicate that cetacean origins is a field that is dynamic, multidisciplinary, and that the end of the explosive phase is not in sight.
Everybody Out of the Pond At the Water's Edge will change the way you think about your place in the world. The awesome journey of life's transformation from the first microbes 4 billion years ago to Homo sapiens today is an epic that we are only now beginning to grasp. Magnificent and bizarre, it is the story of how we got here, what we left behind, and what we brought with us. We all know about evolution, but it still seems absurd that our ancestors were fish. Darwin's idea of natural selection was the key to solving generation-to-generation evolution -- microevolution -- but it could only point us toward a complete explanation, still to come, of the engines of macroevolution, the transformation of body shapes across millions of years. Now, drawing on the latest fossil discoveries and breakthrough scientific analysis, Carl Zimmer reveals how macroevolution works. Escorting us along the trail of discovery up to the current dramatic research in paleontology, ecology, genetics, and embryology, Zimmer shows how scientists today are unveiling the secrets of life that biologists struggled with two centuries ago. In this book, you will find a dazzling, brash literary talent and a rigorous scientific sensibility gracefully brought together. Carl Zimmer provides a comprehensive, lucid, and authoritative answer to the mystery of how nature actually made itself.
