ipl-logo

Neutral Theory Of Natural Selection Report

683 Words3 Pages

Background
The theories of evolution-selection and neutral—explain the mechanism by which evolution come about. These theories disagree on the proportions of the kinds of mutations/changes (advantageous, deleterious and neutral) that contribute to evolution. In addition the theories disagree on the fact that either the trait (allele) established in the population are a function of random chance events or is a function of carefully selected non-random adaptive process. Natural selection favours the latter, while neutralists favour the former.

The selection theory
The natural selection theory postulate that most mutation/changes that lead to evolution are deleterious, a few are neutral and very few are advantageous. The mutations are essential …show more content…

Hence, random genetic drift is, by far, the dominant mechanism molecular of evolution and explains the variation within and between species. For example, if a population carries several different alleles of a particular gene, chances are that each of those alleles is equally good at performing its job. Hence none of the alleles can be said to be more fit than the other. Allele frequencies in small populations do not generally reflect those of larger populations since too small of a set of individuals cannot represent all of the alleles for the entire population. Genetic drift occurs when the population size is limited and therefore by chance, certain alleles increase or decrease in frequency. Unlike natural selection, genetic drift is random and rarely produces adaptations to the environment. It is important to note however that the neutral theory does not suggest that: organisms are not adapted to their environments; all morphological variation is neutral; all genetic variation is neutral and that natural selection is unimportant in shaping genomes. It in facts believes that natural selection helps to rapidly purge the genome of deleterious …show more content…

It is a non-random process
Changes which are established in the population are not necessarily adaptive. They are a function of chance Changes are directed towards heritable adaptations which are best fitted for the current environment
Genetic drift acts upon the genotypic frequencies within a population without regard to their phenotypic effects—silent or neutral mutations which do not reflect any observable phenotypic change Favours the spread of alleles whose phenotypic effects increase survival and/or reproduction of their carriers, lowers the frequencies of alleles that cause unfavourable traits, and ignores those that are neutral
Summarily focuses on the evolutionary changes occurring at the molecular level Places more emphasis on the evolution of physical traits or

Show More
Related
648 Words | 3 Pages

Mutations deals with the production of DNA cells based on a natural selection by chance. Genetic Drift is solely based on changes and has nothing to do with natural selection. Non-Random mating deals with that populations that chooses their mates based of their

Read More
760 Words | 4 Pages

The purpose of this experiment was to conduct a long-term population genetics study by observing five generations of Drosophila melanogaster to determine the allele frequencies of eye color. Population genetics is the study of distribution and change in allele frequency in a population (). This makes population genetics important to the study of evolutionary biology as it examines adaptations, speciation, and the population structure of a population under study (). Two important processes of population genetics that will be examined in this experiment are natural selection and genetic drift, both that are important to evolution ().

Read More
466 Words | 2 Pages

This, along with tests for neutral evolution that the researchers conducted, allowed them to conclude that balancing selection occurred on the ABO gene and that neutral evolution could not have occurred, especially in a region of the sequence

Read More
1027 Words | 5 Pages

Mutation did occur in some of the rounds we did in the experiment by having more birds with longer beaks and smaller ones decreasing dramatically. But eventually birds with smaller beaks will adapt to another environment and as for long beak birds they will have to challenge one another to fight for food and probably over time have a hard time searching for food. But it wasn’t natural selection that changed the beak size of the birds it was basically a mutation that was passed on to their

Read More
1256 Words | 6 Pages

However, it is much more noticeable in small populations. It takes a great deal of time for the effects of genetic drift to be noticeable in a larger population as there is a much larger gene pool present (Masatoshi & Fumio, 1981). The statement made by the professor, that genetic drift is only relevant in small populations is not entirely correct. Genetic drift can occur in large populations but is much less noticeable than in a smaller population with a

Read More
752 Words | 4 Pages

Natural Selection Characteristic determination is that it is the system by which a living being that is most appropriate to its condition will survive and pass on its useful qualities in expanding numbers to the accompanying eras, while those life forms less suited to the earth will be disposed of. . “For example, some cheetahs can run faster than other cheetahs and will therefore be more likely to catch their prey. Organisms that blend into their background and remain hidden from their predators will have a better chance of surviving than those members of their species that cannot” (Arnold, 2009). “Peppered moths - the deer mice are like the classic example of natural selection the peppered moths of northern England” (Arnold, 2009).

Read More
930 Words | 4 Pages

Seth Justus English 2 Mr. Johnson Project Eagle Paper on Charles Darwin Thesis Statement: Charles Darwin shaped evolutionary Biology into the way we see it today with his writings on how genetic variations of species between generations, how climate and many other things can cause variations between species, and just his idea of survival of the fittest in The Origin of Species. Primary Source: The Origin of Species The Origin of Species by Charles Darwin, published on November 24th 1859 is considered to be the foundation to evolutionary biology. The Origin of Species introduces the scientific theory that populations of species evolve over long periods of time through the process of Natural Selection.

Read More
530 Words | 3 Pages

Genetic drift and fire is one of the few mechanisms of evolution. Genetic drift or allelic drift doesn't work to produce adaptations, in fact, it can cause populations to lose genetic variation. Allelic drift "occurs when the population size is limited and therefore by chance,

Read More
585 Words | 3 Pages

Student loans have always seem to be a controversial topic. Many people are in agreement and disagreement over the opportunity to student loans. Student loans can be a great advantage to many students, but it can also drown them in an immense debt, that will follow them for many years. The more we analyze this perspective, we are able to distinguish the advantages and disadvantages of student loans. There is a variety of perspectives on student loans, some involving annual salaries, interest rates, and commodity.

Read More
517 Words | 3 Pages

In the book, The Time Machine , the Time Traveller theorizes about how the Morlocks and the Eloi people evolved. Darwin’s theories are reflected in the Time Traveller’s theories on human evolution. One of these theories is that humans will continually evolve. Another theory is that natural selection means that organisms that have the most favorable traits survive, prosper, and maintain those favorable traits. The final theory is that in nature, organisms are limited in their ability to survive, based on how their surrounding climate changes.

Read More
1250 Words | 5 Pages

In 1859, Charls Darwin set out his theory of evolution by natural selection as an explanation for adaptation and speciation. Charles Darwin theory of natural selection is one of the corner stones of morden biology. The concept, published by Darwin and Alfred Russel Wallace in a joint presentation of papers in 1858, was elaborated in Darwins influencial 1859 book on the origins of species. Darwins ideas, along with Adam Smith and Karl Max had a profound influence on 19th century thought. The influence of Darwins theory has spread from evolutionary biology to other disciplines, including evolutionary computation, quantum Darwinism, evolutionary

Read More
722 Words | 3 Pages

A disadvantage of artificial selection is stated on, “Lee County Students”, saying that “However, genetic modification is highly controversial.” This is a disadvantage because artificial selection is not fully proven to work, and there are not many studies that show it works easily. Another disadvantage of artificial selection is an unexpected result. There are many different outcomes of artificial selection and can be a surprise to the organism and owner, stated on “Pros and Cons of Artificial Selection”. A final disadvantage of artificial selection is shortened life.

Read More
1666 Words | 7 Pages

The population must be large so that no genetic drift (random chance) can cause the allele frequencies to change. 5. No selection can occur so that certain alleles are not selected

Read More
1006 Words | 5 Pages

Three different sides will be discussed in this paper. First is the theory of natural selection, often called the survival of the fittest. Natural selection as quoted by the Merrium Webster Dictionary is, “a natural process that results in the survival and reproductive success of individuals or groups best adjusted to their environment and that leads to the perpetuation of genetic qualities best suited to that particular environment.” For example there is a litter of cats. One of these cats is a lot faster than the other cats and is therefore able to get food easier.

Read More
1251 Words | 6 Pages

Population evolution can occur by genetic drift; this is a change in the gene pool of a small population due to change. Gene flow is also a cause of population evolution, this happens when a population loses or gains alleles by gene flow. Natural selection also causes population evolution, this promotes evolutionary adaption. The general outcomes of natural selection are directional selection, disruptive selection, and, stabilizing selection. Population evolution can also occur by sexual selection.

Read More

More about Neutral Theory Of Natural Selection Report

Related Topics

Open Document