biodiversity
	The genetic, species, and ecological diversity of the organisms in a given area.
endangered species
	A species considered to be in imminent danger of extinction.
existence value
	The importance we place on just knowing that a particular species or a specific organism exists.
extinction
	The irrevocable elimination of species; can be a normal process of the natural world as species out-compete or kill off others or as environmental conditions change.
gap analysis
	A biogeographical technique of mapping biological diversity and endemic species to find gaps between protected areas that leave endangered habitats vulnerable to disruption.
genetic assimilation
	The disappearance of a species as its genes are diluted through crossbreeding with a closely related species.
habitat conservation plans
	Agreements under which property owners are allowed to harvest resources or develop land as long as habitat is conserved or replaced in ways that benefit resident endangered or threatened species in the long run. Some incidental "taking" or loss of endangered species is generally allowed in such plans.
island biogeography
	The study of rates of colonization and extinction of species on islands or other isolated areas based on size, shape, and distance from other inhabited regions.
threatened species
	While still abundant in parts of its territorial range, this species has declined significantly in total numbers and may be on the verge of extinction in certain regions or localities.
vulnerable species
	Naturally rare organisms or species whose numbers have been so reduced by human activities that they are susceptible to actions that could push them into threatened or endangered status.

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