Coloniality In The Cliff Swallow PDF Download

The Nebraska Sandhills is the largest area of sand dunes in the western hemisphere, covering an area about as large as Vermont, New Hampshire, and Rhode Island combined. Unlike most dunes, the Sandhills region supports an astonishing variety of wildlife. Sixty million years ago the area lay submerged in a vast inland sea. As the land lifted and the waters receded, the sandhills were formed, built upon a sandy floor above a sandy basement. Paul A. Johnsgard's appreciation for the region includes its evolution, a process that continues today making a very special place, patiently shaped by water, wind, and time. Sometimes 450 feet higher than their sloping valleys, the hills themselves are almost entirely covered with plants that manage to survive on an unstable substrate and in a climate of merciless heat and cold. They provide homes and resting places for rare species and sustain the livelihoods of a remarkable variety of people. Though firmly established in science, this book is an extended love letter to the Sandhills region and its people, plants, and animals. Johnsgard is now in his third decade of research in the Sandhills. This Fragile Land lets others see what he sees, a land with a fascinating range of geological, biological, and ecological vistas. Paul A. Johnsgard is Foundation Professor of the School of Biological Sciences at the University of Nebraska-Lincoln. Widely published throughout the English-speaking world, he has become a foremost authority on ornithology and bird behavior. His thirty-three books include Birds of the Great Plains, The Platte, Birds of the Rocky Mountains, Those of the Gray Wind, and Diving Birds of North America, all available from the University ofNebraska Press.