The study of dispersal of plants on the globe involves the consideration of nature and factors of dispersal, dispersal of flowering plants, role of man in plant dispersal etc. Nature and Factors of Dispersal: The present-day distribution of plants over the globe is the result of migration of plants over time into ecologically suitable areas. The spread or migration of [...]
In this article we will discuss about the role of main in plant dispersal. After the Great Ice Age of Pleistocene period man has emerged as the greatest and most powerful modifier of the environmental conditions of the biosphere because of his skill and technological advancement. In fact, man has introduced a new period of 'organic upheaval' in the organic [...]
In this article we will discuss about the extinction of animals that takes place in a number of ways due to variety of causes. Speciation (evolution of new species) and species extinction (complete elimination of species) are the natural processes which follow the evolution of animals. It is believed that about 200 species of mammals and birds have become extinct [...]