Darwin's Four Postulates

Rodrigo Páramo Biology P.3

Charles Darwin was an english naturalist that is well know for his contributions regarding evolution in species. He came up with four basic postulates or statements whihc are the ones I will explain in depth next.

Variation among individuals within species

This postulate consist on the variation there is within a certain species. Keeping in mind that there are millions of species around the world, Darwin researched and came up with the statement that variation exists within subjects in a species. One experiment in which he proved this postulate was with domestic animals, specially dog breeding. He talked about the idea that you can talk about dogs but there are dogs from small chihuahua all the way to Saint Bernard. There are both dogs but they are, as individual subjects, hugely different from one another. If you think about it, it is a simple matter. You can look among your friends and people in general and see the differences. Another thing Darwin talked about was the differences in plants. There are many different plants around the world and it is important to know that they don't react the same to different substances or weather. For example, some plants can behave differently in hot temperatures than other or vise versa.

Organisms produce more offspring than their environment could support

On this statement Darwin argued that organisms produced an amount of offspring that their environment would never be able to maintain. Taking into consideration that there are many organisms from mammals, all the way to plants or trees that produce an massive amount of young or seeds and an environment wound't be saturated it they would all survive to maturity. Some examples are the Salmon, the Oak Tree, the Oyster and the Elephants. The amount of offspring they produce is huge! An oyster can produce 114,000,000 eggs, while a female Salmon can produce up to 28,000,000 eggs! If you think about it, the world would be saturated by oysters and salmon if they were all to survive until maturity and reproduction age.

Competition exists among individuals

This statement is regarding the fact that not all young survive to maturity age. This statement shares some characteristics from the one above but this is about how they survive and the competition there is to survive. There is direct competition which is the one that young form the same species compete to survive. This consists on foxes racing a rabbit and the first fox to get the rabbit is the one to eat that day. This rule is true for all the species, whether it is to chase an animals for alimentary factor or find shelter or hiding places. This is a competition where the individual that does it correctly and gets to survive is the one who will get to reproductive age or maturity and he will be able to reproduce and pass on its genes.

Survival of the fitest

In this statement Darwin argued that those organisms that had the best fittest variations were the ones who were be able to survive. In humans, characteristics are mainly physical and don't matter as much as in animals. In animals, for example, an individual that is faster than another will have more possibility of surviving than the slower one. Another example is skin color. In class yesterday we were playing a game were we changed environments and factors in order to see how rabbits coexisted within them. This is a good example of this postulate since we learned simple things like when a rabbit is in an environment that the ground color is the same color as the rabbits fur, or a very similar color, it has much more possibilities of surviving than a rabbit that has the fur color very differently than the ground color. The term I refer to as survival of the fittest is practically that the organist that it best fit to the environment will be the one who will survive and therefore reproduce and pass on its genes to further generations.


Fox and rabbit [Personal photograph]. (2015, January 9).

Milne, B. (n.d.). Arctic Hare. Retrieved April 08, 2016, from http://www.arkive.org/arctic-hare/lepus-arcticus/image-G70312.html

Petersen, C. (n.d.). Research Interest. Retrieved April 08, 2016, from https://www.nceas.ucsb.edu/~petersen/

Pojeta, J., Jr., & Springer, D. A. (2001). Evolution and the Fossil Record. Retrieved April 08, 2016, from http://www.agiweb.org/news/evolution/darwinstheory.html

St Bernard and chihuahua [Personal photograph taken in Manchester]. (1970, June).