Charles Darwin's Four Postulates

Theory of Evolution

Charles Darwin's Four Proposed Mechanism for Evolution.

  1. The possibility for a species to increase in number.
  2. Genetic variation of species are due to mutation and sexual reproduction.
  3. Competition for resources.
  4. Natural selection of organisms which adapt better to their given environment.

What It Actually Means

Population Growth

Population growth takes places because species produce more offspring because not all offspring will survive. There are many environmental, human and genetic factors that affect the outcomes.

Genetic Variation

Genetic Variation is found within populations where organisms express individual variation in behaviour and appearance. These variations include body size, hair colour, number of offspring, markings and voice properties.

Competition For Resources

Competition for resources is the product of diverse species battling for food. The interaction of animals for the same supply of resources leads to unstable communities and to the decline and survival of these same animals.

Natural Selection

Natural selection is the process by which organisms and species adapt to the changes in their environment. The animals that tend to survive go on to produce more offspring, while those that cannot adapt do not survive. Due to this, the animals become more adept to their surroundings and evolve with their changing environment.


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