Succession and Natural Selection

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Succession and Natural Selection Student: University: Ecosystem-Succession Animation Succession is the gradual change of species inhabiting an ecosystem due to environmental or edaphic factors. The succession animation ecosystem depicts a form of secondary succession, supported by the fact that: i. Existence of soils that supported the forest vegetation (primary succession occurs in areas in which originally there was no soil) ii. There was a presence of pre-existing forest vegetation, after which a series of events occurred; damming the stream which resulted in the area becoming flooded, and hence creation of a pond. The roots became waterlogged; an unsuitable condition for the trees and death resulted. This created conditions favorable for the sedge grass which however, altered the ecosystem to be less favorable for them and they are succeeded by the sphagnum and moss. The sedge grasses formed the peat due to decomposition. The peat accumulated and gradually reduced the pond size and depth until the pond disappeared, resulting into a small stream. The peat provided the substrate for the growth of trees over time; a bog forest was the final succession. Darwin’s Four Premises of Evolution by Natural Selection: 1. Differential reproductive success This suggests that individuals who possess the most favorable traits survive through generations by passing these traits to the following generation, by sexual reproduction. Combinations of different traits result in entirely new species different from its ancestors. 2. Overproduction Species reproduce a large number of offspring, but only a few survive to reach the reproductive stage. 3. Restrains on population growth Resources such as food are limited and only those individuals that are able to acquire these resources survive. 4. Variation Individuals vary in their traits, and these
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