Without evolution, and the constant ever changing environment, the complexity of living organisms would not be as it is. Evolution is defined as a process that results in heritable changes in a population spread over many generations (8).Scientists believe in the theory of evolution. This belief is based on scientific evidence that corroborates the theory of evolution. In Figure 1 the pictures of the skulls depict the sequence of the evolution of Homo-sapiens. As the figure shows, man has evolved from our common ancestor that is shared by homo-sapiens. The change of diet of homo-sapiens over time has thought to contribute to the change in jaw structure and overall skull shape.
The process of evolution comprises of many complex of mechanisms. These mechanisms fundamentally allow the progression of speciation and adaptation to occur. There are 4 common kinds of evolutionary mechanism of change: Natural Selection, Genetic Drift, Mutation and Migration.
Natural selection is based on the concept “survival of the fittest” where the most favourable individual best suited in the environment survive and pass on their genes for the next generation. Those individual who are less suited to the environment will die.
Another mechanism is a hereditable type of evolution is mutations. Mutations are alterations to a gene. Mutation can be harmful, beneficial or neutral. Mutations are the origin of the source of genetic diversity (9).Mutation that are harmful, hinders the chances of the organism chances of survival and are likely to die along with the mutations. Beneficial mutations increase the chances of the individual to survive in its environment, and they will be more likely to reproduce and pass on the gene to future generations (9).
Migration is a movement of populations, groups or individual (13). Migration creates gene flow, where one gene moves from one population to another (13).Migrations will affect the gene frequency over evolutionary time. The effects of migration are to increase variability in and to prevent the population of the organism from diverging and to the extent where speciation occur between the same organisms (14).
Genetic drift is a mechanism of evolution that occurs by random chance rather than natural selection (15).Genetic drift will continue until the involved allele is either lost in the population or is the only allele presents it the population (16).Genetic drift causes a new population which is genetically distinct from its original population, which led to a hypothesis that genetic drift plays in a role of the evolutionary mechanism.
The theory of evolution and the mechanisms as scientist knows as today, were originally not believed and existed until two scientists; Jean- Baptiste Lamarck and Charles Darwin discovered the theory of evolution each with different beliefs.
Lamarck proposed his theory of evolution, he believed that the evolutionary improvements happen because of used and disuse and the inheritance of...