Darwin's Four Postulates

Mafer Villarreal

1: There is Variation Among Individuals

All over the ecosystem we can see different types of animals and flowers. One example is "¾ of the plants had flowers that were almost pure white, with just two spots of yellow on the lower lip." This proves there are always going to be different types of things that can represent the whole population even if we are talking about the same thing. They can have several variations like color, "¼ of the population of plants had flowers that were solid yellow."

2. Some of the Variation is Heritable

Sometimes the things and traits that we have are due to our ancestors and the things that we have in our past that can help shape us. For example the "dominant allele S expressed white flowers with two yellow spots, while the recessive trait ss is expressed as the yellow flower." There are two key reasons why most phenotypes are not inherited as simple Mendelian traits. Many traits are affected not by one, but by multiple genes.

3. Do individuals vary in Their Success at Reproducing?

Each plant and organism has a different way of reproducing and we can see that is may vary depending on the atmosphere and on the variations that may be affecting it. Consistent with Darwin’s 3rd postulate, the plants showed considerable variation in reproductive success, both as pollen donors and as seed producers. You can use a table to track down how much the plants grow to get a good conclusion.

4. Is Reproduction nonrandom?

There have been scientific theories that tell us that it could go either way. Reproduction can cause attraction, for example "White flowers attracted twice as many bees as yellow flowers." and some similar example prove that the data shows that reproductive success is not random.

APA Citations

Natural selection. (2016).Evolution.berkeley.edu. Retrieved 6 April 2016, from http://evolution.berkeley.edu/evolibrary/article/evo_25


Reproduction, a high quality journal publishing research into the cellular and molecular biology of reproduction . (2016). Reproduction-online.org. Retrieved 6 April 2016, from http://www.reproduction-online.org/


variation | biology. (2016). Encyclopedia Britannica. Retrieved 6 April 2016, from http://global.britannica.com/science/variation-biology