The Río Mayo region of northwestern Mexico is a major geographic area whose natural history remains poorly known to outsiders. Lying in a region where desert and tropical, northern and southern, and continental and coastal species converge, it boasts an abundance of flora first documented by Howard Scott Gentry in 1942 in a book now widely regarded as a classic of botanical literature. This new book updates and amends Gentry's Río Mayo Plants. Undertaken with Gentry's support and participation before his death in 1993, it reproduces the original text, which appears here with annotations, and contains information on over 2,800 taxa—more than twice the 1,200 species first described by Gentry. The annotated list of plants includes information on distribution, habitat, appearance, common names, and indigenous uses. A new introduction provides historical background and a review of geography and vegetation. It also describes changes to the land and river wrought by agricultural development, expanded grazing, and lumbering. Throughout the text, the authors have endeavored to provide information on Río Mayo vegetation while emphasizing local knowledge and use of plants, to preserve Gentry's field-oriented focus, and to present botanical information with Gentry's exuberance and style. Río Mayo Plants has long stood as a book that displays a scientist's love of the English language, his fondness for native peoples, and his eye for beauty in nature. This updating of that work fills a gap in the botanical literature of this portion of North America and will be useful not only for botanists but also for biogeographers, taxonomists, land managers, and conservationists.
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.
One of the most recognizable animals of the Southwest, the desert tortoise (Gopherus agassizii) makes its home in both the Sonoran and Mohave Deserts, as well as in tropical areas to the south in Mexico. Called by Tohono O'odham people "komik'c-ed," or "shell with living thing inside," it is one of the few desert creatures kept as a domestic pet—as well as one of the most studied reptiles in the world. Most of our knowledge of desert tortoises comes from studies of Mohave Desert populations in California and Nevada. However, the ecology, physiology, and behavior of these northern populations are quite different from those of their southern, Sonoran Desert, and tropical cousins, which have been studied much less. Differences in climate and habitat have shaped the evolution of three races of desert tortoises as they have adapted to changes in heat, rainfall, and sources of food and shelter as the deserts developed in the last ten million years.
This book presents the first comprehensive summary of the natural history, biology, and conservation of the Sonoran and Sinaloan desert tortoises, reviewing the current state of knowledge of these creatures with appropriate comparisons to Mohave tortoises. It condenses a vast amount of information on population ecology, activity, and behavior based on decades of studying tortoise populations in Arizona and Sonora, Mexico, and also includes important material on the care and protection of tortoises. Thirty-two contributors address such topics as tortoise fossil records, DNA analysis, and the mystery of secretive hatchlings and juveniles. Tortoise health is discussed in chapters on the care of captives, and original data are presented on the diets of wild and captive tortoises, the nutrient content of plant foods, and blood parameters of healthy tortoises. Coverage of conservation issues includes husbandry methods for captive tortoises, an overview of protective measures, and an evaluation of threats to tortoises from introduced grass and wildfires. A final chapter on cultural knowledge presents stories and songs from indigenous peoples and explores their understanding of tortoises.
As the only comprehensive book on the desert tortoise, this volume gathers a vast amount of information for scientists, veterinarians, and resource managers while also remaining useful to general readers who keep desert tortoises as backyard pets. It will stand as an enduring reference on this endearing creature for years to come.