The eohippus, or dawn horse, first appeared approximately 55 million years ago, stood no larger than a dog, and had four toes on its front legs and three on its hind legs; remains have been found in Wyoming’s Wind River Basin. Over time, the eohippus evolved into Equus, the horse as it is known today. Horses became extinct in America about 8,000 years ago, and Spanish explorers and missionaries reintroduced them to the Americas in the fifteenth century. According to legend, today’s wild horses descend from animals that escaped early Spanish expeditions, but large numbers of wild horses did not appear on the plains grasslands until after the 1680 Pueblo Revolt. Wild horses in the McCullough Peaks vicinity are part of the Wyoming Bureau of Land Management Herd Management Area, a fifteen mile, 109,814 acre public rangeland roughly 12 miles east of Cody, Wyoming, where the Bureau of Land Management strives to maintain a herd of approximately 100 animals. These horses show many coat colors and patterns, are moderate to large in size, and are usually in superb physical condition. Typical colors include brown, black, chestnut, sorrel, white, buckskin, palomino, gray, blue, red, and strawberry roan, and patterns such as piebald and skewbald are common. The Bureau of Land Management National Wild Horse and Burro Program provides for adoption of wild horses and burros removed from public lands, with legal transfer taking place after the animals have been properly cared for during the initial adoption year. Their protection, control, and management are provided for by the 1971 Wild Free-Roaming Horse and Burros Act and later laws, including the 1978 Public Rangelands Improvement Act, which define responsibilities for monitoring and balancing rangeland values, including wild horses.