Common patterns of biodiversity can be observed with changes in elevation, including: a) decreasing species richness (i.e. the number of species) as elevation increases and b) a peak in richness at intermediate elevations, with lower richness at the base and top of the mountain.

Mid- elevational areas will receive sink populations from source populations both above and below, whereas the upper and lower part of the gradient will only receive sink species from one direction. This will create a humped pattern, with maximum species richness in the middle of the elevational gradient.

Biodiversity. the variety of species/ life in an ecosystem, it includes where the organisms live and the genetic variation between different species and within a species itself.

Biodiversity is the variety of different forms of life on earth, including the different plants, animals, micro-organisms, the genes they contain and the ecosystem they form. It refers to genetic variation, ecosystem variation, species variation (number of species) within an area, biome or planet.