The Mexican Plateau, in its magnificent dimensions and material wealth, stood among the first and perhaps most alluring discoveries of European explorers. Bur ied deeper in the verbal histories of a now vanquished people, the American Indians, must be the primordial human awareness of the inverted complex triangle that dominates the Mexican topography, climate and biota. It always has been viewed by man as a source of wealth and a center of authority. The plateau is the pillar upon which all Mexican conquerors have erected their capitols, tilled their crops and mined for their treasure, and from which they dispersed the forces of their authority. Ironically, the same size and diversity that give the plateau its value, also make it an immense barrier. Its broad desert and three to five thousand meter high crests constitute severe obstacles in the path of North American man. What has just been said of mankind in general, can be applied to the biologist in particular. He too has termed the goliath southern plateau as the crucible of the arid biotas of the continent (i. e. , 'Madro-Tertiary'). The biologist found the plateau to be a region of tremendous richness and diversity. But he also has been inhibited both physically and intellectually by its high mountain and vast desert barriers.

Over the past thirty years, late Quaternary environments in the arid interior of western North America have been revealed by a unique source of fossils: well-preserved fragments of plants and animals accumulated locally by packrats and quite often encased, amberlike, in large masses of crystallized urine. These packrat middens are ubiquitous in caves and rock crevices throughout the arid West, where they can lie preserved for tens of thousands of years. More than a thousand of these deposits have been dated and analyzed, and middens have supplanted pollen records as a touchstone for studying vegetation dynamics and climatic change in radiocarbon time (the last 40,000 years). Now, similar deposits made by other mammals like hyraxes are being reported from other parts of the world. This book brings together the findings and views of many of the researchers investigating fossil middens in the United States, Mexico, Africa, the Middle East, and Australia. The contributions serve to open a forum for methodological concerns, update the fossil record of various geographic regions, introduce new applications, and display the vast potential for fossil midden analysis in arid regions worldwide. The findings presented here will serve to foster regional research and to promote general studies devoted to global climate change. Included in the text are more than two hundred charts, photographs, and maps.

Environmental and specific diversity in the Chihuahuan desert in general, and in the Cuatro Ciénegas Basin in particular, has long been recognized as outstanding. This book provides a global ecological overview, together with in-depth studies of specific processes. The Chihuahuan desert is the warmest in North America, and has a complex geologic, climatic and biogeographical history, which affects today’s distribution of vegetation and plants and generates complex phylogeographic patterns. The high number of endemic species reflects this complex set of traits. The modern distribution of environments, including aquatic and subaquatic systems, riparian environments, gypsum dunes and gypsum-rich soils, low levels of phosphorous and organic matter, and high salinity combined with an extreme climate call for a range of adaptations. Plants are distributed in a patchy pattern based on punctual variations, and many of them respond to different resources and conditions with considerable morphological plasticity. In terms of physiological, morphological and ecological variability, cacti were identified as the most important group in specific environments like bajadas, characterized by high diversity values, while gypsophytes and gypsovagues of different phylogenies, including species with restricted distribution and endemics.

Typical development in the American Southwest often resulted in scraping the desert lands of the ancient living landscape, to be replaced with one that is human-made and dependent on a large consumption of energy and natural resources. This transdisciplinary book explores the natural and built environment of this desert region and introduces development tools for shaping its future in a more sustainable way. It offers valuable insights to help promote ecological balance between nature and the built environment in the American Southwest-and in other ecologically fragile regions around the world.

Described as "a writer in the tradition of Henry David Thoreau, John Muir, and other self-educated seers" by the San Francisco Chronicle, David Rains Wallace turns his attention in this new book to another distinctive corner of California—its desert, the driest and hottest environment in North America. Drawing from his frequent forays to Death Valley, Red Rock Canyon, Kelso Dunes, and other locales, Wallace illuminates the desert’s intriguing flora and fauna as he explores a controversial, unresolved scientific debate about the origin and evolution of its unusual ecosystems. Eminent scientists and scholars appear throughout these pages, including maverick paleobiologist Daniel Axelrod, botanist Ledyard Stebbins, and naturalists Edmund Jaeger and Joseph Wood Krutch. Weaving together ecology, geology, natural history, and mythology in his characteristically eloquent voice, Wallace reveals that there is more to this starkly beautiful landscape than meets the eye.

This book describes the biodiversity and biogeography of nothern Mexico, documents the biological importance of regional ecosystems and the impacts of human land use on the conservation status of plants and wildlife. It should become the standard source document for the conservation status of species and ecosystems in this region, which is of unusual biological interest because of its high biodiversity and highly varied landscape and biological zonation.

This volume investigates the contemporary fauna that inhabit the Cuatro Ciénegas Basin. Divided into 15 chapters, it addresses and describes their diversity, taxonomic and biogeogaphic affinities, and ecological characteristics. The Cuatro Ciénegas Valley is a unique oasis in the south-central region of the State of Coahuila, part of the Sonoran Desert, in Mexico. Several clues, specially derived from the study of the microbiota, suggest a very ancient origin of the valley and its permanence through time. This condition had promoted a high level of endemism and led to unique interactions between the resident species.

From two veteran ecologists comes a new and sweeping exploration of the natural history of Texas in all its biological diversity and geological variation. Few states, if any, can match Texas for its myriad species, past and present, and its many distinctive landscapes, from prairie grasslands and hardwood forests to coastal lagoons and desert mountains. Beginning with the stories of how biologists and naturalists have over time defined the ecological areas of this very big state, the authors visit each of the eleven regions, including the Texas coast. They describe the dominant flora and fauna of each, explain the defining geologic features, and highlight each region’s unique characteristics, such as carnivorous plants in the Piney Woods and returning black bears in the Trans-Pecos. Throughout, the authors remain especially conscious of the conservation and management issues affecting the natural resources of each region, revealing their deep affection for and knowledge about the state. Bolstered by a glossary, further reading suggestions, a description of state symbols, and an appendix of scientific names, this is an educational and essential volume for all Texans. ECOREGIONS Piney Woods Post Oak Savanna Blackland Prairies Cross Timbers and Prairies Rolling Plains Edwards Plateau High Plains Trans-Pecos South Texas Brushland Coastal Prairies Texas Gulf Coast

IN THIS REVISED edition of Amphibians and Reptiles of Texas, James R. Dixon adds to and updates the extensive information given in the first edition. A new section on conservation issues highlights some of the problems facing the continued survival of amphibians and reptiles, particularly commercial collecting and habitat destruction. Taxonomic changes have been made to reflect the latest scientific information, and the extensive listing of the literature on Texas amphibians and reptiles has been updated through April, 1999. Going back to the writings of French botanist Jean Louis Berlandier, who encountered Texas herpetofauna during his travels from 1828 to 1834, this list covers more than 150 years of inquiry into the state's species and is also testimony to the distinguished careers of such herpetologists as Hobart M. Smith and, more recently, Chris McAllister. Another prominent feature of this book is the more than 150 distribution maps, which show by county the updated distribution records for all native Texas amphibians and reptiles, based on more than 13,000 county records and more than 110,000 individual localities. Professional and amateur herpetologists as well as environmentalists, wildlife specialists, campers, and hikers will find the dichotomous keys useful for identifying species at hand. This aid to identification is supported by a glossary, drawings and photographs, and complete scientific and common names.