Darwin's Four Postulates

Rodrigo Segovia

Evolution and Natural Selection

Darwin's ideas were that species survived and adapted because of four rules:

1. Variation within species- Species differ and have different variations between them.

2. Variation is heritable- DNA and heritage is what makes people get traits. And some may be advantageous and some may be disadvantageous.

3. Overproduction- Species have to produce more of the young in order to survive.

4. Non-random survival- This is the main idea of Natural Selection, that survival is not random but it is by natural selection for the evolution of the species.


Ch 3. Darwinian Natural Selection. (n.d.). Retrieved April 06, 2016, from http://faculty.buffalostate.edu/penaloj/bio405/outline3.html

Huntington disease. (n.d.). Retrieved April 06, 2016, from https://ghr.nlm.nih.gov/condition/huntington-disease

Huntington's disease. (n.d.). Retrieved April 06, 2016, from http://www.mayoclinic.org/diseases-conditions/huntingtons-disease/basics/definition/con-20030685

Natural selection. (n.d.). Retrieved April 06, 2016, from http://evolution.berkeley.edu/evolibrary/article/evo_25