Conservation biology, or conservation ecology, is the science of analyzing an protecting Earth's biological diversity. Conservation biology is an interdisciplinary subject drawing on biological, physical and social sciences, economics, and the practice of natural-resource management. The rapid decline of biological systems around the world means that conservation biology is often referred to as a "Discipline with a deadline". Conservation ecology addresses population dynamics issues associated with the small population sizes of rare species (e.g., minimum viable populations). The term "conservation biology" refers to the Conservation biology is the scientific study of the phenomena that affect the maintenance, loss, and restoration of biological diversity and the application of science to the conservation of genes, populations, species, and ecosystems. For the history of biodiversity conservation and volunteer activity, see conservation movement.