Nature & Science
Yellowstone National Park is as wondrous as it is complex. Established primarily to protect geothermal areas that contain about half the world's active geysers, the park also forms the core of the Greater Yellowstone Ecosystem. At 28,000 square miles, it is one of the largest, nearly intact temperate-zone ecosystems on Earth. It preserves a great variety of terrestrial, aquatic, and microbial life. Natural processes operate in an ecological context that has been less subject to human alteration than most others throughout the nation—and throughout the world. This makes the park not only an invaluable natural reserve, but a reservoir of information valuable to humanity.
The pages in our Nature & Science section are intended to help you understand important concepts about Yellowstone's many resources and issues, including geology, hydrothermal features, volcanic and earthquake activity in Yellowstone, scientific research, and wildlife.
Yellowstone's abundant and diverse wildlife are as famous as its geysers. There are 67 species of mammals, including 7 species of native ungulates, 2 species of bears, 330 species of birds, 16 species of fish, 4 species of amphibians, and 6 species of reptiles. It is rare that animals and humans can be in such close proximity. In Yellowstone we get to see what animals do in their natural habitat. Learn More…
The vegetation communities of Yellowstone include overlapping combinations of species typical of the Rocky Mountains as well as of the Great Plains to the east and the Intermountain region to the west. The exact vegetation community present in any area of the park is the consequence of the underlying geology, ongoing climate change, substrates and soils, and disturbances created by fire, floods, landslides, blowdowns, insect infestations, and the arrival of nonnative plants. Learn More…
Environmental FactorsSizes, boundaries, and descriptions of any ecosystem vary. In general, we say that the Greater Yellowstone Ecosystem consists of 12-22 million acres and 18,750-28,000 square miles. It is located in Wyoming, Montana and Idaho and encompasses state lands, two national parks, portions of five national forests, tthree national wildlife refuges, BLM holdings and private and trible lands. Learn More…
Other Life Forms
The hydrothermal features of Yellowstone are magnificent evidence of Earth's volcanic activity. Amazingly, they are also habitats in which microscopic organisms called thermophiles—"thermo" for heat, "phile" for lover—survive and thrive. Learn More…
ResearchIn Yellowstone, scientists conduct research ranging from large studies of landscape-level changes affecting the local ecosystem to studies of tiny organisms that have the potential to change the lives of people the world over. Learn more…
Yellowstone Science-Related Links From Non-NPS Sources
Did You Know?
At peak summer levels, 3,500 employees work for Yellowstone National Park concessioners and about 800 work for the National Park Service.