The Phorusrhacids (which means "rag bearers"), popularly known
as "terror birds" were large carnivorous flightless birds
that were native to South America - although some species did
manage to establish themselves in North America after the
Isthmus of Panama land bridge arose about 3 million years ago.
Phorusrhacids first appeared in the Paleocene epoch, about
62 million years ago, and survived until the late Pliocene,
about 2 million years ago.
Many Phorusrhacids were quite small, about to 2 to 3 feet (0.6 to 0.9 meters)
tall, but the largest species were enormous standing 10 feet (3 meters)
tall. The larger species were almost certainly fast runners, and might have been
able to reach speeds of as much as 30 mph (48 km/h).
Phorusrhacids are believed to have generally had beaks with a hooked-curve,
similar to that of an eagle, and additionally their feet may have had sharp claws.
Generally speaking, most Phorusrhacids had shorty, stubby and effectively useless
wings, however the wings of one genus, Titanis, seem to have a joint-like
structure, digits that could flex to some degree (unlike the fused digits of most birds),
and may even have ended in a clawed finger.
Product Description: Modern birds (Neornithes) are represented by two big lineages, the Palaeognathae (Tinamiformes + Ratitae) and the Neognathae [Galloanserae + Neoaves (Metaves + Coronoaves)]. Both clades sum approximately 10,000 species of which 60% are Passeriformes (the most diverse clade of terrestrial vertebrates). A comparison between the past and the present reveals a complex and hallmarked evolutionary and biogeographic history which would have begun over 65 million years ago. For South America (SA) this includes: (1) the presence of taxa with uncertain affinities and the absence of Passeriformes during the Paleogene; (2) a progressive and accelerated increase of the species starting at the Neogene (Miocene); (3) important extinct lineages (e.g. Phorusrhacidae, Teratornithidae) that migrate to North America after the rising of the Panamá isthmus; (4) groups with major diversification in the Neogene that survives nowadays represented by scarce species endemic of SA (Cariamidae) or that inhabits mainly in the southern hemisphere (Anhingidae); (5) very diverse living groups with scarce (e.g., Passeriformes) or none (e.g., Apodiformes) fossil record in SA, which stem-groups are registered in Europe. Apparently, the changes in diversity of the south American Neornithes have been the result of successive radiation, biogeographic connections with North America and in a minor scale, some extinctions. The opening of the Drake´s passage and the occurrence of the circumpolar Antarctic flow are not sufficient causes to explain the highly disparity between the weddelians penguins (Sphenisciformes) of Antartica and those of the patagonian Atlantic Ocean.
Product Description: In the present book the Paleogene fossil record of birds is detailed for the first time on a worldwide scale. I have developed the idea for such a project for several years, and think that it is an appropriate moment to present a summary of our c- rent knowledge of the early evolution of modern birds. Meanwhile not only is there a confusing diversity of fossil taxa, but also significant progress has been made concerning an understanding of the higher-level phylogeny of extant birds. Hypotheses which were not considered even a decade ago are now well supported by independent analyses of different data. In several cases these group together morphologically very different avian groups and allow a better understanding of the mosaic character distribution found in Paleogene fossil birds. The book aims at bringing some of this information together, and many of the following data are based on first-hand examination of fossil specimens.
Over millions of years, Australia’s unique biodiversity has produced a large cabinet of curiosities. Among the weirder members of this group were the Mihirungs, members of the now extinct family Dromornithidae. Made up of several genera of flightless birds—among them one of the very largest birds that ever lived—the dromornithids ranged from 60-kilogram beasts, 1.5 meters tall, to giants twice that size, weighing nearly half a metric ton. They were, by orders of magnitude, the largest "geese" that ever lived. One species was comparable in size to the Ele-phantbird of Madagascar and the Giant Moa of New Zealand. This book is the first major study of this unique and highly diverse group. It aims to present as complete a synthesis as possible of current information about this fascinating family of birds.
Product Description: Coastal exposures of the Santa Cruz Formation in southern Patagonia have been a fertile ground for recovery of Early Miocene vertebrates for more than 100 years. This volume presents a comprehensive compilation of important mammalian groups which continue to thrive today. It includes the most recent fossil finds as well as important new interpretations based on 10 years of fieldwork by the authors. A key focus is placed on the paleoclimate and paleoenvironment during the time of deposition in the Middle Miocene Climatic Optimum (MMCO) between 20 and 15 million years ago. The authors present the first reconstruction of what climatic conditions were like and present important new evidence of the geochronological age, habits and community structures of fossil bird and mammal species. Academic researchers and graduate students in paleontology, paleobiology, paleoecology, stratigraphy, climatology and geochronology will find this a valuable source of information about this fascinating geological formation.
Why Elephants Have Big Ears is the result of one man's lifelong quest to understand why the creatures of the earth appear and act as they do. In a wry manner and personal tone, Chris Lavers explores and solves some of nature's most challenging evolutionary mysteries, such as why birds are small and plentiful, why rivers and lakes are dominated by the few remaining large reptiles, why most of the large land-dwellers are mammals, and many more.
Product Description: An exploration of all that is known about the origin of birds and of avian flight. It draws on fossil evidence and studies of the structure and biochemistry of living birds to present knowledge and data on avian evolution and to propose a new model of this evolutionary process.
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