Chapter 15 Study guide-Hardy Weinberg and Genetic Drift, Bottleneck, Mechanisms of Evolution Videos

What are the two types of genetic drift and explain them?

1. Founders Effect- When a small sample of a population settles in a location separated from the rest of the population 2. Bottleneck- occurs when a population declines from a catastrophic disaster and rebounds

What are the mechanisms of evolution (these are basically all violations of Hardy-Weinberg)-big concept map **5 things**

1. Genetic Drift 2. Gene Flow 3. Non-random Flowing 4. Mutation 5. Natural Selection

How does gene flow occur (2 things)?

1. Increases genetic variation 2. reduces differences

What are the 4 types of natural selection and how do they occur?

1. stabilizing selection- eliminates an extreme 2. directional selection- against one extreme/ makes one more fit 3. disruptive selection- splits a population into 2 4. sexual selection- male attracts a female with traits that dont seem to help them survive

What is an example of founder's effect?

A small group of rabbits leave a population of them. In the actual population no fur rabbits were rare, but in the new smaller population the no fur rabbits are not so rare anymore.

What is an example of a bottleneck?

An earthquake happens and kills half a population of rabbits and kills all the no fur rabbits and some with fur. Later the new population is full of fur rabbits and there are none with no fur.

What is the Hardy Weinberg Principle/Equilibrium?

When allele frequencies in populations are stable and unchanging (not evolving).

What is an example of sexual selection?

male competition- males fighting over female choice

What is industrial melanism and what happens to the allele frequencies of the different moths?

the prevalence of dark-colored varieties of moths in industrial areas where they are better camouflaged against predators than paler forms. The allele frequencies depend on the environment.