The Phylogeny of Hornless Ruminants and a Description of the Cranium of Archaeomeryx
The Phylogeny of Hornless Ruminants and a Description of the Cranium of Archaeomeryx

Author: Sawney David Webb

Publisher:

Published: 1980

Total Pages: 54

ISBN-13:

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"We analyze the interrelationships of the several groups of hornless ruminants and show which of them lie nearest the higher ruminants. The phylogenetic progression within Ruminantia proceeds from Hypertragulidae through Tragulidae to Leptomerycidae to Gelocidae to Moschidae and thence to the horned ruminants. Archaeomeryx of the late Eocene is recognized as a primitive member of the Leptomerycidae; the living Tragulidae actually represent a more primitive ruminant stock. We introduce the name Moschina for the Gelocidae and the Moschidae and the term Eupecora for the higher ruminant groups bearing horns, antlers, and ossicones. We also propose Neoselenodontia, above the subordinal level, to include both the Ruminantia and their sister group, the Tylopoda. The stratigraphic records of the five lower ruminant families appear relatively complete with the exception of the Tragulidae, which are poorly known prior to the Miocene. The exclusively North American distribution of the family Hypertragulidae and many of the Tylopoda suggests that the Ruminantia may have originated in North America. The Tragulidae, exclusively Old World and predominantly subtropical, presumably originated by colonization and isolation in the Old World. Thereafter ruminant evolution centered in the Old World, but representatives of every major group reached North America"--P. 121.

Effects of Past Global Change on Life
Effects of Past Global Change on Life

Author: National Research Council

Publisher: National Academies Press

Published: 1995-02-01

Total Pages: 267

ISBN-13: 0309051274

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What can we expect as global change progresses? Will there be thresholds that trigger sudden shifts in environmental conditionsâ€"or that cause catastrophic destruction of life? Effects of Past Global Change on Life explores what earth scientists are learning about the impact of large-scale environmental changes on ancient lifeâ€"and how these findings may help us resolve today's environmental controversies. Leading authorities discuss historical climate trends and what can be learned from the mass extinctions and other critical periods about the rise and fall of plant and animal species in response to global change. The volume develops a picture of how environmental change has closed some evolutionary doors while opening othersâ€"including profound effects on the early members of the human family. An expert panel offers specific recommendations on expanding research and improving investigative toolsâ€"and targets historical periods and geological and biological patterns with the most promise of shedding light on future developments. This readable and informative book will be of special interest to professionals in the earth sciences and the environmental community as well as concerned policymakers.

Horns, Tusks, and Flippers
Horns, Tusks, and Flippers

Author: Donald R. Prothero

Publisher: JHU Press

Published: 2002

Total Pages: 334

ISBN-13: 9780801871351

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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.

Patterns in the Structure of Mammalian Communities
Patterns in the Structure of Mammalian Communities

Author: Douglas W. Morris

Publisher:

Published: 1989

Total Pages: 274

ISBN-13:

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Addresses the evolutionary ecology of various closely related, well- known mammals. Contributions address issues of habitat selection, species interaction, distribution, abundance, and diversity. Habitats under study include deserts, tropical and boreal forests, heaths, swamps, and savannas. No index. Annotation copyrighted by Book News, Inc., Portland, OR

Living Fossils
Living Fossils

Author: N. Eldredge

Publisher: Springer Science & Business Media

Published: 2012-12-06

Total Pages: 445

ISBN-13: 1461382718

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The case history approach has an impressive record of success in a variety of disciplines. Collections of case histories, casebooks, are now widely used in all sorts of specialties other than in their familiar appli cation to law and medicine. The case method had its formal beginning at Harvard in 1871 when Christopher Lagdell developed it as a means of teaching. It was so successful in teaching law that it was soon adopted in medical education, and the collection of cases provided the raw material for research on various diseases. Subsequently, the case history approach spread to such varied fields as business, psychology, management, and economics, and there are over 100 books in print that use this approach. The idea for a series of Casehooks in Earth Science grew from my experience in organizing and editing a collection of examples of one variety of sedimentary deposits. The prqject began as an effort to bring some order to a large number of descriptions of these deposits that were so varied in presentation and terminology that even specialists found them difficult to compare and analyze. Thus, from the beginning, it was evident that something more than a simple collection of papers was needed. Accordingly, the nearly fifty contributors worked together with George de Vries Klein and me to establish a standard format for presenting the case histories.