Define historical example population genetic theory, Biology

Assignment Help:

Define Historical Example Population genetic theory?

Population genetic theory, first developed by Sir Ronald Fisher, JBS Haldane and Sewall Wright, demonstrated how several evolutionary and demographic forces will influence levels of genetic variation in a population. Whereas mutation increases genetic variation, random genetic drift removes it. The strength of drift is proportion to the opposite of the effective population size (Wright 1931). So, population genetic theory predicts that genetic variation within a population should increase along with population size.

If population sizes fluctuate over time, the long-term average effective population size is more sensitive to the lower population sizes as compared to the higher ones. For instance, consider an insect population that over the course of each year undergoes three generations with population sizes of 10, 100 and 1000. Were it to frequently fluctuate among these three population sizes, its effective population size would be approximately 30-- far lower than the arithmetic mean of 370. So, periodic bottlenecks in population size will sharply decrease the effective population size and therefore genetic variance.


Related Discussions:- Define historical example population genetic theory

Difference between distant object and near object, Difference between Dista...

Difference between Distant object and Near object - Distan t object Near object   1. Parallel light reaches to eye.   2. Ci

Define mechanism for provide protection against colon cancer, Define Mechan...

Define Mechanisms for Provide protection against colon cancer? Several plausable mechanisms have been formulated by which fibre may provide protection against colon cancer. The

Pox diseases, P o x diseases Small-pox in human beings and pox in a f...

P o x diseases Small-pox in human beings and pox in a few animal species are closely related to each other. It is shown by the fact that the vaccine for the prevention of sma

Explain about the browning reactions, Explain about the Browning Reactions?...

Explain about the Browning Reactions? The Browning Reactions are complex reactions which occur when foods are processed. In some the brown flavour is highly desirable and is in

Phylum sarcomastigophora - protozoan, Phylum Sarcomastigophora Locomo...

Phylum Sarcomastigophora Locomotory organelles - flagella, pseudopodia or both types, usually with one type of nucleus; typically no spore formation, sexual reproduction thro

Nested brackets as a cladogram, using either nested brackets as a cladogram...

using either nested brackets as a cladogram, what are the hierarchical relationships among the followingtaxa:raniates, amniotes, mammals, actinopterygians, chondrichthyes, aves, ve

Concept of universality of the genetic code, Q. What is the concept of univ...

Q. What is the concept of universality of the genetic code? What are the exceptions to this universality? The genetic code is universal because the rules of protein codificatio

Explain the food preparation and cooling - canning, Explain the Food prepar...

Explain the Food preparation and Cooling - Canning? Food preparation - Preparation methods will change with the type of food. For fruit, cutting to size, washing, grading, peel

Hominid phylogeny, In the above sections we discussed in detail the fossil ...

In the above sections we discussed in detail the fossil record of primates in general and more particularly those of apes and the humans. Despite the fact that in recent years a nu

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd