A broad survey of biodiversity—past, present, and future—with an emphasis on major groups in the tree of life (e.g., insects, plants, vertebrates, fungi, bacteria, etc.) and how humans interact with Earth’s biodiversity. Biodiversity is explored as it relates to Earth's history, mass extinctions, conservation, economics, ecology, evolution, and human society. Also explores ways in which biodiversity is categorized (taxonomy and systematics) and cataloged for study (museums).