Insect dispersal rates are rapid in response to the availability of suitable habitats. At the end of the last glaciation the Bering land bridge joined Alaska and the Russian Far East. Much of Alaska was not glaciated during the Wisconsin glaciation. The inter-tropical convergence zone in January is positioned north of the Equator. Vegetation facilitates the penetration of water into the soil by reducing the kinetic energy of the falling raindrop.
Desertification is caused by climatic change.
There is a direct positive correlation between high amounts of plant biomass, and the nutritional quality of that biomass. In the Sahel, herbivores mainly utilize vegetation with a low protein content. An anomalous pool of warm surface water collects in the eastern southern Pacific Ocean. Upwelling of cold water off the Peruvian coast stops. Rates of decomposition are slow.