In your own words, provide the essential points of Charles

Darwin’s theory of evolution by natural selection (descent with

modification).

Darwin’s Theory of EvolutionDescent With Modification

• Fertility is so high that populations would increase exponentially if all offspring survived

• Most species have stable numbers

• Natural resources are finite / limited

• Therefore, there is a struggle for existence, and only a fraction of offspring survive.

Darwin’s Theory of Evolution by Natural Selection

• More offspring are produced than can be supported by the environment (struggle for existence)

• All individuals vary• Some of the variation is inherited by the offspring

(offspring resemble parents)• In the struggle for existence, favored variants are more

likely to survive & reproduce (survival of the fittest)• Therefore, populations change over time as favored

variants become are preserved and become more common (descent with modification)

• Individuals in a population differ; no two are exactly alike

• Much of the variation is heritable

• Survival in the struggle for existence is not random, but tends toward those that have inherited favorable variations

• Therefore, the unequal ability of individuals to survive and reproduce leads to gradual change in a population, with favorable characteristics increasing in frequency

Darwin’s Theory of EvolutionDescent With Modification