Development and Diversification of Living Organisms - Assignment Example

Evolution The process of development and diversification of living organisms from earlier forms is known as evolution. The development and diversification are dependent on the environmental factors that contribute to the reproduction and growth of species. These include the natural selection mechanisms such as food and shelter that enable species to survive, physical characteristics, also known as the genes that vary and are inherited. The evolution of populations can take place in the form of macroevolution and microevolution.

In the former, very large changes occur over long periods of time. On the contrary, in the latter, small changes in a population occur within the same area, resulting in interbreeding. The complete set of genes within a living organism's cell is called genotype. On the other hand, the complete set of physical characteristics that make up the structure of an organism is called phenotype. The limitations of these factors will inhibit the reproduction process, which of course results differently from one species to another because of the differences in characteristics that are inherited and environment influences.

This variation is also the result of a process called mutation, which are caused by radiation, viruses and errors during DNA replication. Genes that arise by mutation and found at the same place on a chromosome is known as allele. Thus, it can be said that evolution is the result of two opposing forces. According to Hardy-Weinberg's Theory, the genotype and allele frequencies of a population will often remain in equilibrium, unless disturbing influences, such as mutation, is present. The equilibrium state is only possible when the genotype and allele frequencies do not change.

This happens when a population has a large size, which prevents the occurrence of genetic drift, bottlenecks and founder effects. The equilibrium state also occurs when there is no mutation, as explained earlier and that random mating takes place, which is explained below. However, this is hardly the case. In other words, if the equilibrium state is violated by factors such as those mentioned above, then evolution will take place. The genotype and allele frequencies are influenced by environmental and cultural events.

A given genotype frequency can occur with random mating in a single generation as this causes the evolution of a given species, which in turn produces a new equilibrium within that one generation. For instance, continuous random mating of black-haired population will result in homozygotes. Such violations include inbreeding, assortative mating and small population size. On the other hand, a change in allele frequency can occur when selection, mutation and migration happen. Thus, the process of evolution that can occur is dependent on environmental and cultural factors.

The equilibrium state can be achieved when Hardy-Weinberg's principles are met. In addition, a new state of equilibrium can also be achieved with random mating. It is also possible to find out the estimated equilibrium state of allele or genotype frequencies in a given population using the two-allele Hardy-Weinberg equation is: p 2 + 2pq + q 2 = 1. *** End *** Reference: Alan E. Stark. (2006). Stages in the Evolution of the Hardy-Weinberg Law.