When considering classical mathematics, the Greeks must be a main focus of our attention. In fact, the primary reason for discussing earlier mathematics is to understand what the Greeks inherited and what they left to their posterity.
The organisms that engage in primary succession are known as pioneer species. Typical pioneer species include simple lichens, algae, and fungi. These simple organisms begin breaking down the resources in the environment and make it suitable for the later introduction of more complex species, such as vascular plants.
  Primary Succession occurs on surfaces where no soil exists, And  Secondary Succession follows a disturbance that destroys a  community without destroying the soil.   Primary succession is slow and secondary succession is rapid.   Primary succession begins in areas where no soil is present.  Secondary succession occurs in areas where there is soil  already present. Primary Succession occurs on surfaces where no soil exists, And  Secondary Succession follows a disturbance that destroys a  community without destroying the soil.   Primary succession is slow and secondary succession is rapid.