Species diversity at the local or community scale. Compare beta diversity, gamma diversity.
beta diversity
The change in species number and composition, or turnover of species, as one moves from one community to another. Compare alpha diversity, gamma diversity.
biogeography
The study of variation in species composition and diversity among geographic locations.
continental drift
The slow movement of tectonic plates (sections of Earth’s crust) across Earth’s surface.
edge effects
Biotic and abiotic changes that are associated with an abrupt habitat boundary such as that created by habitat fragmentation.
endemic
Occurring in a particular geographic location and nowhere else on Earth.
equilibrium theory of island biogeography
A theory proposing that the number of species on an island or in an island-like habitat results from a dynamic balance between immigration rates and extinction rates.
gamma diversity
Species diversity at the regional scale; the regional species pool. Compare beta diversity, alpha diversity.
local scale
A spatial scale that is essentially equivalent to a community.
regional scale
A spatial scale that encompasses a geographic area where the climate is roughly uniform and the species contained therein are often restricted to that region by their dispersal capabilities.
regional species pool
All the species contained within a region; sometimes called gamma diversity.
species–area relationship
The relationship between species richness and area sampled.
turnover
The replacement of one species with another over time or space.
vicariance
An approach to biogeography that explains the geographic distribution of species in terms of events such as continental drift that result in the geographic isolation of populations that once were connected to one another.
