FOR201H1 Chapter Notes - Chapter 8: Endemism, Primary Production, Species Complex
Document Summary
Chapter 8 - so many species, so many theories: Altitudinal gradients are relatively analogous to latitudinal gradients. Species diversity increases dramatically from polar to tropical regions. A difference is that diversity often peaks at mid-altitudes. Rainfall, soil moisture, and evapotranspiration peak at intermediate elevations. There"s likely high diversity due to high primary productivity. Bats have a continuous decline in diversity with increasing altitude. Another difference is that broad-leaved evergreen trees have continued dominance despite declining temperatures along the elevation gradient. May be explained by low tropical climatic seasonality. Many tropical rainforests have high endemism, a measure of biological uniqueness. There"s a broad correlation between richness and endemism with plants and mammalian species. Endemics: are species restricted to particular areas. Definitions based on political boundaries are useful for conservation initiatives. Island habitats such as mountaintops possess a high proportion of localized endemics, as isolation allows for speciation. Some species are widely distributed despite having narrow habitat requirements.
