THE FOUR POSTULATES:
(1) The potential for a species to increase in number.
(2) The heritable genetic variation of individuals in a species due to mutation and sexual reproduction.
(3) Competition for limited resources.(4) The proliferation of those organisms that are better able to survive and reproduce in the environment.
1. POTENTIAL FOR A SPECIES TO INCREASE IN NUMBER
2. HERITABLE GENETIC VARIATION
Because we inherit our traits from two different organisms (mom & dad), we often look like a combination of both. However, there are some things that are out of our control like mutations in our genotype, which then result in changes in our phenotype. This too, adds to the variation in a certain species.
4. ADVANTAGEOUS TRAITS
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