Sections
                          Key Terms
                      Key Terms
- adaptive radiation
 - rapid branching through speciation of a phylogenetic tree into many closely related species
 
- biodiversity
 - variety of a biological system, typically conceived as the number of species, but also applying to genes, biochemistry, and ecosystems
 
- biodiversity hotspot
 - 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
 - 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
 - variety of metabolic compounds in an ecosystem
 
- chytridiomycosis
 - disease of amphibians caused by the fungus Batrachochytrium dendrobatidis; thought to be a major cause of the global amphibian decline
 
- DNA barcoding
 - molecular genetic method for identifying a unique genetic sequence to associate with a species
 
- ecosystem diversity
 - variety of ecosystems
 
- endemic species
 - species native to one place
 
- exotic species
 - (also, invasive species) species that has been introduced to an ecosystem in which it did not evolve
 
- extinction
 - disappearance of a species from Earth; local extinction is the disappearance of a species from a region
 
- extinction rate
 - number of species becoming extinct over time, sometimes defined as extinctions per million species–years to make numbers manageable (E/MSY)
 
- genetic diversity
 - variety of genes in a species or other taxonomic group or ecosystem, the term can refer to allelic diversity or genome-wide diversity
 
- heterogeneity
 - number of ecological niches
 
- megafauna
 - large animals
 
- secondary plant compound
 - compound produced as byproducts of plant metabolic processes that is usually toxic, but is sequestered by the plant to defend against herbivores
 
- species-area relationship
 - 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
 - economic principle that resources held in common will inevitably be overexploited
 
- white-nose syndrome
 - disease of cave-hibernating bats in the eastern United States and Canada associated with the fungus Geomyces destructans