1. Agenda 10/3 Hardy-Weinberg Introduction
Hardy-Weinberg Practice problems
Turn in: Nothing?
Homework
1) Hardy-Weinberg worksheet (on website)
2) Work on proposal
3) Study for Unit Exam

2. How do we know evolution has occurred?

3. How do we know evolution has occurred?
If the allele frequencies change from one generation to the next
Hardy-Weinberg is used to determine the expected allele frequencies with NO evolution and can then be used to compare to the actual population to determine if any change (evolution) has occured

4. Hardy-Weinberg
Hardy-Weinberg is a mathematical formula that predicts frequencies for alleles assuming NO evolution occurs
Hardy-Weinberg will be true for a population if
1. No genetic changes (no mutations)
2. No gene flow (no immigration/emigration)
3. No genetic drift (large population size)
4. No sexual selection (random mating)
5. No natural selection (all phenotypes are equally able to survive and reproduce)
Will these conditions ever be met?

5. HW is a Null Hypothesis
A null hypothesis is a hypothesis you DO NOT expect to be true
You hope to ‘reject’ the null to prove your point
HW is used to detect changes in allele frequencies which gives us a simplified method to determine if evolution is occurring
If a population is evolving you would reject the null hypothesis based on the values you get by using the hardy-Weinberg equation