Transcript In your own words, provide the essential points of Charles Darwin`s

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 Evolution
Descent 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)
Darwin’s Theory of Evolution
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