Yellowstone National Park is a true wilderness area. Over ninety-nine percent of the park supports the continent's largest and most diverse wildlife habitats. Yellowstone is home to a remarkable variety of birds, fish, and mammals and is recognized worldwide as a protected wildlife sanctuary. Over 300 animal species cohabitate in the area known as the Greater Yellowstone Ecosystem. These species include 60 mammals, 225 bird species, and 18 different types of fish. Animal wildlife that a visitor to Yellowstone might hope to see include grizzly and black bear, bison (American Buffalo), moose, Bighorn sheep, wolves, elk, deer, beaver, marmots, osprey, bald eagles, and others too numerous to mention. The word "Yellowstone" may have originated from the Sioux Indians who referred to the yellow bluffs along the Yellowstone River as the "Mitse-a-da-zi", later interpreted to mean "Yellow Rock River" by French Canadian trappers who visited the area in the late 16th century. They coined the name "Roche Jaune" or "Yellow Rock" from which the modern name was derived.
Yellowstone is one of the most geologically unique areas in the world. The majority of the Park sits atop a geothermal "hotspot" in the mantle of the earth, a geologic layer just below the earth's crust. This concentrated hotspot under the earth provides the heat necessary to drive the incredible hydrothermal features and volcanic activity.
The geothermal features of Yellowstone are a unique phenomenon of remarkable interest and comprise the world's greatest concentration of geysers and hot springs. A large collapsed volcano known as a caldera exists in the southern portion of Yellowstone and is a remnant of a major volcanic eruption that occurred about 1,200,000 years ago. The last continental glaciation ended about 10,000 years ago and resulted in the melting of the Yellowstone ice cap. Visible effects of those glaciers are evidenced by the large "erratic" boulders scattered across northern Yellowstone that were deposited by the melting icecap, as well as the glacial "moraines" in the mountains surrounding Yellowstone National Park Yellowstone Lake, the largest high mountain lake in North America at an elevation of 7733 feet fills part of the huge caldera. A variety of fossil remains have been discovered in and around Yellowstone. They include more than ten layers of petrified forests preserved by periodic volcanic eruptions. In addition, Paleontologists have discovered dinosaur remains in the Greater Yellowstone Region including the Late Cretaceous Sauropod.
The Greater Yellowstone Region has a diverse and dynamic history and culture and over the years has attracted explorers, miners, and trappers (the so-called "mountain men".) Today Yellowstone continues to attract people worldwide from outdoor adventure enthusiasts and vacationers to scientists and researchers. Early human occupation of the park is evidenced by numerous artifacts and campsites left by the Native Americans who lived in the Yellowstone area. Some of these cultural sites date back nearly 12,000 years and suggest that prehistoric hunter-gathers lived in the area known today as the Greater Yellowstone Region. Several tribes of Native American Indians traveled at various times through the Yellowstone area in search of hunting opportunities. Evidence of tribes in the area includes the Flathead, Blackfeet, Sioux, Crow and Shoshone. A small group of Shoshone Indians known as the Sheepeaters returned each summer to the Yellowstone plateau. They lived a more primitive existence and primarily hunted bighorn sheep in the more rugged areas and fished in the Madison, Gallatin, Snake, and Yellowstone river drainages.