Key Terms

biodiversity

the variety of a biological system, typically conceived as the number of species, but also applying to genes, biochemistry, and ecosystems

biodiversity hotspot

a concept originated by Norman Myers to describe a geographical region with a large number of endemic species and a large percentage of degraded habitat

bush meat

a wild-caught animal used as food (typically mammals, birds, and reptiles); usually referring to hunting in the tropics of sub-Saharan Africa, Asia, and the Americas

chemical diversity

the variety of metabolic compounds in an ecosystem

chytridiomycosis

a disease of amphibians caused by the fungus Batrachochytrium dendrobatidis; thought to be a major cause of the global amphibian decline

ecosystem diversity

the variety of ecosystems

endemic species

a species native to one place

exotic species

(also, invasive species) a species that has been introduced to an ecosystem in which it did not evolve

extinction

the disappearance of a species from Earth; local extinction is the disappearance of a species from a region

extinction rate

the number of species becoming extinct over time, sometimes defined as extinctions per million species–years to make numbers manageable (E/MSY)

genetic diversity

the variety of genes and alleles in a species or other taxonomic group or ecosystem; the term can refer to allelic diversity or genome-wide diversity

habitat heterogeneity

the number of ecological niches

secondary plant compound

a compound produced as a byproduct of plant metabolic processes that is typically toxic, but is sequestered by the plant to defend against herbivores

species-area relationship

the relationship between area surveyed and number of species encountered; typically measured by incrementally increasing the area of a survey and determining the cumulative numbers of species

tragedy of the commons

an economic principle that resources held in common will inevitably be over-exploited

white-nose syndrome

a disease of cave-hibernating bats in the eastern United States and Canada associated with the fungus Geomyces destructans