Allele frequencies are p = 0.3 and q = 0.7. What is the expected heterozygosity 2pq?

Answer: ______________

What does expected heterozygosity measure?

• The chance two random gene copies differ
• The number of species in a forest
• The age of the oldest allele

Expected heterozygosity is the chance that two gene copies picked at random from a population differ.

Circle one:   True   False

A between-population index comes out near zero. What does that mean?

• The populations are fully isolated species
• No genes exist in either group
• The populations mix freely and stay similar

Out of 100 gene copies, 40 are A and 60 are a. What is the expected heterozygosity?

Answer: ______________

A pooled sample shows far fewer heterozygotes than 2pq predicts. Why?

• Heterozygotes always die young
• The sequencer hides every heterozygote
• It mixes two groups with different versions

Observed heterozygotes fall well below the prediction. What is the next step?

• Split the sample and check for hidden structure
• Declare evolution disproven at once
• Delete the rare allele from the data

Two samples carry mostly different versions and their index is high. What do you conclude?

• One freely mixing population
• Two isolated groups with little gene flow
• A lab mix-up with no meaning