The document discusses endangered species and defines key related terms. It notes that endangered species indicate environmental problems and their protection could benefit human lives and planet health. Habitat loss, hunting, pollution and other factors can endanger species by reducing populations and driving them to extinction, as was the case for prairie dogs, blue whales, and bald eagles. The U.S. Endangered Species Act of 1973 aims to protect disappearing plants and animals. Individual actions like learning about and volunteering to help local endangered species can support conservation efforts.