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Types of Evolution. Artificial Selection (done by humans) Natural Selection Random Process. Artificial Selection. HUMANS DECIDE who breeds with who!. Artificial Selection. PROBLEMS ! Selecting AGAINST something may be bad Mursa. The Liger. Natural Selection.
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Types of Evolution • Artificial Selection (done by humans) • Natural Selection • Random Process
Artificial Selection HUMANS DECIDE who breeds with who!
Artificial Selection • PROBLEMS! • Selecting AGAINST something may be bad • Mursa
Natural Selection • The ENVIRONMENT determines which individuals survive and reproduce! • Wallace & Darwin • Are you fit enough to survive? • Do you have any traits (adaptations) to help you survive?
Natural Selection • Species produce an overabundance of offspring • Not all offspring survive • Individuals differ in their traits • (differences in) traits can be passed from parent to offspring • Differences in traits reflected in the ability to survive & reproduce
Natural Selection • Fitness • Adaptations • Where are all the short eared bunnies? • Ex: Living in the desert
Random Process • (1) Mutation • (2) Genetic Drift • (3) Bottleneck Effect • (4) Founder Effect
Bottlenecks • Human caused: • Habitat loss • Hunting • Changes to the environment (GCC) • Natural: • Natural disaster • Outcome • Decreased genetic variation, increased diseases, low fertility
Natural Selection & Herbicides • PROBLEMS! • Herbicide resistant weeds • ex: Boliviananegra