What is the genetic pool?

The genetic pool it is the totality of the genetic material of a population group in a certain period. In general, this concept refers to a set of individuals belonging to the same species with all their genes, their combinations and alleles. Alleles are the variants of genes.

Due to evolutionary processes, the composition of the genetic group of a population can change. This change allows populations to adapt to the characteristics of their environment..

In this transformation of the genetic pool there are several mechanisms involved such as mutations and natural selection. The adaptability of different populations could be influenced by the size of their gene pool. This would explain why some groups are more successful than others when facing abrupt changes in the environment..

Genetic pool and microevolution

Microevolution occurs when there is a recombination of the existing genetic material within the group, producing subtle changes in the genetic pool. These changes are naturally limited; that is, the probability of a drastic change is unlikely.

This microevolution explains the fact that there are varieties within the same group. Thus, a descendant is different from his ancestor, but clearly belongs to the same type..

A clear example of microevolutionary changes is the color range of the human eye. Another example that serves to illustrate this fact is the resistance that insects develop to certain repellants..

Main mechanisms involved in the change of the genetic pool

Mutations

One of the basic mechanisms in gene pool change is mutation. These change the actual DNA of an organism. Favorable, unfavorable, or neutral mutations can occur. Frequencies in favorable alleles increase with each generation.

A change in DNA in gametes can be inherited, creating new alleles or eliminating existing traits. However, cells self-control to prevent or correct mutations and preserve the genetic pool.

Selection

Charles Darwin's theory of natural selection explains the main mechanism for microevolution. If the alleles are favorable for the reproduction of the species, they are transferred to future generations.

In this way the unfavorable alleles disappear from the gene pool. If the different generations are compared, the changes in the allele frequency are evidenced.

Migration

Migratory movements, within or outside a population, can cause changes in the genetic traits of both the host population and the one left behind..

In the first case, there must be a coupling with the introduction of new alleles. Emigration, on the other hand, results in the loss of alleles. This results in a decrease in the genes available in the genetic group of origin..

Genetic pool and macroevolution

Macroevolution refers to significant evolutionary changes over time. It describes patterns in the tree of life on a large scale over extended periods of time..

Some of these patterns include stability, gradual change, rapid change, adaptive radiation, extinctions, the co-evolution of two or more species, and convergent evolution in traits between species, among others..

References

1. Sultan Haque, O. (2013, August 29). Gene pool. Encyclopædia Britannica, inc. Recovered from britannica.com.
2. Morris, J. D. (1996). What Is The Difference Between Macroevolution And Microevolution? Acts & Facts, 25 (10).
3. Scoville, H. (2017, July 09). What Causes Microevolution? Why Should I Care? Thoughtco. Recovered from thoughtco.com
4. McClean, P. (1997). Population and evolutionary genetics. North Dakota State University. Recovered from ndsu.edu.
5. Sesink Clee, P. and Gonder, M. K. (2012) Macroevolution: Examples from the Primate World. Nature Education Knowledge, 3 (12): 2.