Darwin's four postulates

Ana Sofia Maldonado Villarreal

Variation - There is a lot of variety within a species

Variation is one of the four postulates of Darwin, its basic definition refers to a genetic event that causes the individuals or groups of certain type or species to possess different characteristics from one another. It is important to know that variation always takes place within limits, this limit is called the “gene pool”, and from this such called “pool”, variation is able to happen. But indeed, variation does not constitute evidence for evolution because variations are but the outcomes of different combination of already existing genetic information. Through variation is impossible to change such reptiles and birds by adding wings or feathers, this requires an increase in genetic information that variation does not offer.

Inheritance - Offspring look like their parents

Darwin's theory of natural selection stated that evolution depends on the existence of heritable variability within a species to allow the generating of differences between ancestral and descendant populations. We can currently see and talk about inheritance everyday, we connect our lives with the ideas that Darwin left behind. For example, it is clear that my brother and me look alike, and we both have similar traits from our parents, this is an great example of inheritance and the ideas of Darwin are clearly proven.

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Differential Survival - External conditions can affect survival

Differential survival is an essential component of Charles Darwin’s theory of natural selection, the idea that the environment is in charge of selecting (all through random chance) which individuals successfully can leave the offspring for the next generation, this is mostly called the “Survival of the Fittest”.

Revealing The "Survival of The Fittest" Origins

Extinction - Some traits are not suited to survival and those with them will die out.

Extinction is part of Darwin's theory of evolution, and it explains how species of living things have changed over time. This theory is fully supported by fossils and by the changes that have been seen in microorganism and bacteria. Darwin believes and talked about how extinction is necessary for evolutionary change. He believed that the idea of improvement with the idea of natural selection changed our valuation of extinction for good.

Darwin's Frog Officially Extinct!

Sources

Sisley, L. C. (2014, May 13). Darwinism Refuted. Retrieved April 04, 2016, from http://www.darwinismrefuted.com/origin_of_species_01.html


Charleswood, B. (2009, November 1). Darwin and Genetics | Genetics. Retrieved April 04, 2016, from http://www.genetics.org/content/183/3/757


Lillyip, R. (2012, July 29). Darwin’s Theory of Evolution. Retrieved April 04, 2016, from http://www.science4all.org/article/darwins-theory-of-evolution/


Polonis, L. (2015, January/February). Ch1. Adaptation by Natural Selection. Retrieved April 04, 2016, from http://www.wwnorton.com/college/anthro/bioanth/ch1/chap1.htm


Pujari, S. (2014, June 19). 4 Main Theories of Evolution (explained with diagram and tables) | Biology. Retrieved April 04, 2016, from http://www.yourarticlelibrary.com/biology/4-main-theories-of-evolution-explained-with-diagram-and-tables-biology/27220/