Free Essay About The Four Forces Of Evolution
Microevolution can be defined as a change in frequency of genes which can be observed over a period of time (normally a short period of time) within a single population due to different processes: mutation, gene flow, genetic drift and selection (either natural or artificial). Microevolution refers to smaller evolutionary changes within a single population in contrast with macroevolution which refers to evolution on a relatively large scale over a long period of time.
The four forces of evolution which bring about microevolution include mutation, genetic drift, selection (natural or artificial) and gene flow. Mutation refers to the changes that occur or take place in an organism’s DNA that leads to different impacts and outcomes in the organism’s life. This can be due to damage in the DNA of the organism, radiation processes or problems in the replication process. Selection is the process by which the best adaptive organisms to a certain environment tend to have an advantage of survival over other species. This leads to these particular species producing more offspring and therefore they are more successful in having many generations of their very own species. Selection can be either artificial or natural. Gene flow can also be referred to gene migration. This is basically the transfer of genes from one population to another. It includes the transfer of genetic material from one place to where a certain population exists to a place where a certain population did not exist before. Genetic drift is a process in which a change in the gene pool or gene variants (alleles) survives strictly by chance over time. It normally occurs in small populations.
A species is a class or a group of individuals or organisms which posses common qualities or characteristics. A common characteristic of a species is the ability to interbreed among themselves and producing offspring. Population can be described as a group of species which have similar characteristics who live in the same geographical area and are also capable of interbreeding. Variation or genetic variation defines the different characteristics within a species. This can be brought about due to environmental effects or genetic differences. Variation in a species can be exhibited by physical appearance or behavior.
Speciation is the process by which new definite biological species are formed from one parent species in the process of evolution. The process by which some properties or traits prevent species from interbreeding or fusing is known as isolation mechanism. These properties may include geographic, ecological or physiological properties. All the forces of evolution affect or have significant impacts on the development of different species as discussed above. The continuity or survival of species is dependent on many properties and aspects that ensure that the best adaptive species inhabit a certain area at a given time which in turn forms a population.