Darwin's Four Postulates
Andrea Suarez
Charles Darwin dedicated his adult life to observe nature and eventually discover Natural Selection (“The Origin of Species” his most famous book).
Natural selection
It is the process by which certain inherited traits make it easier for some individuals to survive and reproduce, eventually changing the genetic makeup of population over time
The most powerful and important cause of evolutionary change1) Variations of Phenotypes
Different members of a population have all kinds of individual variations, this characteristics (body size, hair color, blood type, metabolism, reflexes) are known as phenotypes
Heritable
These variations are heritable and can be passed on to the organism’s offsprings. In order for the favorable trait to be helpful for the population, the organism must be able to pass it on to future generations.
Populations can have more offspring than resources (food & water) can support.
Darwin called this the struggle for existence, inspired by the work of Thomas Malthus who said that when human population gets to big, we face things like wars, famines and plagues.
Survival and Reproduction Rates
Those with favorable traits are more likely to survive and reproduce. It is also based on the previous ideas.
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https://www.amherst.edu/media/view/178820/original/Bio32-W3-lecture-post.pdf
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http://faculty.evansville.edu/de3/b32003/lecture%20summaries/selection.pdf
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