Darwin's Four Postulates

By Ricardo Villarreal Chapa

Who is Darwin?

Charles Darwin (1809 - 1882) is considered to be the "father of evolution". He was a man that dedicated his life to science and he was able to develop several theories about it. Although he came to the same conclusion at nearly the same time as another scientist, people were more inclined to listen to him because he was more prominent in the scientific world.

He wrote a book titled On the Origin of Species that went into quick success, as it's first and second printing sold out immediately. His ideas and theories became so influential in the scientific world that it didn't take time for them to spread into society. Some say that his theories created a "societal transformation".


Darwin's theories consist of two main things: (1) the diversity of groups of animals that evolve from one or more ancestors and (2) the mechanism by "which this evolution takes place is natural selection".


In this Smore I will explain to you thoroughly Darwin's four main postulates!

1. Variation

Variation is the quantity and variety of unique sets of traits that each individual has in a given population. They come from several sources, such as mutation and sexual reproduction.

It can be inferred that they come from mutation as the alteration of the existing genes form new alleles, and then they can arise and copy new errors during DNA replication (as well as DNA Damage and then recombine during cell division).

On the other hand, they can also come from sexual reproduction where new combinations of DNA are created through independent assortment of genes.

2. Inheritance

This postulate is important because it takes into consideration the genes from both parents and all other ancestors. It states that an offspring has the possibility of inherit special traits from either one or both parents.

An example to back up this statement takes us back to an assignment we did before spring break. It involved a game where we would choose special physical traits to rabbits and as time went by and as they reproduced themselves, the recipient offspring would either inherit the black fur or they would stick to the white fur. This allowed us to see that as evolution goes by, it takes into consideration all of the hereditary traits that have gone out through all history.

3. Different Survivals

This postulate is not only important but it is known for it to be called Natural Selection. This is a process which results in the adaptation of an organism to its environment by means of specific reproducing changes in its genetic constitution.

In this process, those variations in the genotype that have an increased an organism's probability of survival and procreation have multiplied from generation to generation at the cost of the less fortunate. This allows evolution to often occur as a consequence of this process.

Extinction

This last postulate occurs when species are ultimately diminished because of environmental causes (such as habitat fragmentation, global change, overexploitation of species for human use) or also because of evolutionary changes in their own members of their specific specie (such as genetic inbreeding, poor reproduction, or decline in population members).

Sources

Brook, E. (2014, February/March). 4 Main Theories of Evolution (explained with diagram and tables) | Biology. Retrieved April 05, 2016, from http://www.yourarticlelibrary.com/biology/4-main-theories-of-evolution-explained-with-diagram-and-tables-biology/27220/



Gittleman, J. L. (2015, October/November). Extinction | biology. Retrieved April 05, 2016, from http://global.britannica.com/science/extinction-biology



T. (2014, July/August). Natural selection | biology. Retrieved April 05, 2016, from http://global.britannica.com/science/natural-selection



Wallow, T., & B. (n.d.). Charles Darwin. Retrieved April 05, 2016, from http://www.biography.com/people/charles-darwin-9266433#related-video-gallery