An essay on the four forces of evolution

Jobs for freelance writers Four Forces of Evolution Evolution is the series of changes by which plants and animals are transformed from their simplest and original states to their present states which are more sophisticated or complex. These changes are continuous and they take place over many generations. Evolutionary changes in plants and animals are genetic properties, characteristics or traits that are being passed down from one generation to the other. The present state of an organism is only a phase in this never-ending process of change.

An essay on the four forces of evolution

Driving Forces of Evolution - Microevolution By: Evolution is no longer termed as a process which involves large variations between generations. The term microevolution has been coined to refer to the variations between generations. The article gives a brief account of the driving forces of this evolutionary mechanism Macroevolution is being replaced by a finer version of collective variations over generations.

This is termed as microevolution which refers to the changes in allele frequency within populations. Microevolution encompasses the processes which cause such changes in allele frequencies from one generation to the next.

Several such processes occurring over of generations result in evolution of species. The fundamental unit of evolution is the population. In general terms, a population consists of interbreeding organisms which occupy a specific habitat at a specific time.

Frequency of the particular allele of the gene in the population is considered as the allele frequency for the purpose of microevolution. The differences in phenotype of populations over generations should be the result of genetic variations. Then only evolution is possible.

There are five forces which play major roles in contributing to such genetic variations. They include mutation, natural selection, gene flow, genetic drift, and non random mating. In terms of fitness, only natural selection strives to make the individual more fit to the environment.

Mutation Mutations are sudden random changes in genetic code which are hereditary in nature and cause a change in phenotype. This can occur at the level of individual genes or nucleotides like point mutations or at the level of chromosomes like the deletions.

Most mutations are either neutral or harmful in effects. Beneficial mutations are very rare in nature. The mutation rates are too slow to cause significant changes in evolution.

An Average mutation rate might take at least generations to reduce the allele frequency of the population by half. They have little effect on the Hardy- Weinberg ratios of the common alleles of genes in a population. But they are the only source of genetic variation resulting in formation of new alleles in a species.

Gene flow or migration Gene flow results in more genetically similar populations. It refers to movement of alleles from one population to another mostly through natural methods.

The resultant populations are more homogenous and have similar allele frequencies. Genetic drift It is the random fluctuation in allele frequency between different generations.

An essay on the four forces of evolution

These effects are more profound in small populations. Allele frequencies may change in generations due to chance. Genetic drift plays a major role in variation in small population since the allelic pool is smaller.

Suppose there is a single allele of a particular gene among a group of 20 organisms.Mechanisms: the processes of evolution. Evolution is the process by which modern organisms have descended from ancient ancestors. Evolution is responsible for both the remarkable similarities we see across all life and the amazing diversity of that life — but exactly how does it work?

The Four Forces of Evolution Essay The Four forces of Evolution Evolution is divided into two categories macroevolution and microevolution; macroevolution focuses on the formation of a new species, while microevolution focuses on the change in allele frequencies in a population (47).

Microevolution (evolution on a small-scale) refers to the changes in allele frequencies within a single population.

Descriptive Essay Example On The Four Forces Of Evolution

Allele frequencies in a population may change due to four fundamental forces of evolution: Natural Selection, Genetic Drift, Mutations and Gene Flow.

The theory of scientific evolution was brought into sociology by Herbert Spencer ( ) in his book Principles of Sociology (). Spencer observed that the study of sociology was, the study of evolution in its most complex form”.

There are four basic models of the BGS relationship: the market capitalism model, the dominance model, the countervailing forces model and the stakeholder model. According to “Business, Government and Society” capitalism is an economic ideology with bundle of values including private ownership of means of production, the profit motive, free.

The essay that follows will discuss the concepts of evolution with a bias on the four forces that fuel or drive evolution.

An essay on the four forces of evolution

Four main forces are believed to drive evolution. As earlier stated, evolution is a continuous process which needs to be driven by some forces.

Descriptive Essay Example On The Four Forces Of Evolution