How is Bio-diversity distributed along major environmental gradients?

Explanation

The latitude or altitude and the enviromental condition are the main gradients of biodiversity of species. The biological diversity increases when one moves from high to low latitude. The favourable environmental conditions favour speciation and make it possibly for a larger number of species to occur and grow. In tropical rain forest,The conditions are favourable for growth throughout the year. But in temperate region,the climate is severe with short growing period for plants.
The decreases in species diversity occur from lower to higher altitudes in mountains. A 100m increase result in a drop of temperature of 6.5 degree celcius. This drop in temperature and greater, seasonal variability in high altitude reduces diversity. Graph showing decrease in number of ant species along the latitudinal gradient.