(From “The Impacts of Sprawl on Biodiversity,” by Elizabeth A. Johnson and Michael W. Klemens, in Nature in Fragments: The Legacy of Sprawl, edited by John and Klemens, and published Columbia University Press, 2005.)

Biological diversity (or biodiversity , for short) is the variety of life on Earth and the interactions, cycles, and processes of nature that link it all together. In its broadest definition, biodiversity includes individual species, the genetic diversity within species, the natural communities in which these species interact, and the ecosystems and landscapes in which species evolve and coexist.… Although conservation efforts to protect biodiversity tend to focus on unique plants or rare animals, biodiversity actually encompasses all nature, including both common and rare components and even more obscure organisms such as fungi and microbes.