Variation With + Among Populations

Question 1

What is the negative frequency-dependent selection

Answer 1

The less common a phenotype is, the higher its fitness

Question 2

What is positive frequency-dependent selection

Answer 2

The more common a phenotype is the higher its fitness

Question 3

What is heterozygote advantage

Answer 3

When different alleles are favoured under different environmental conditions heterozygous individuals may outperform homozygotes

Question 4

What is the continental island model

Answer 4

• One way gene flow from a large continental mainland population to a smaller island population
• allele frequency on the island changes at a rate that depends upon the rate of gene flow and difference in allele frequency between the island + the mainland

Question 5

What is the island model

Answer 5

Describes gene flow among many populations exchanging immigrants with one another

Question 6

What is the stepping stone model

Answer 6

Allow subpopulations to exchange individuals only with adjacent subpopulations
- 2 subpopulations that are far apart will experience little gene flow + will be more different that 2 subpopulations closer together
- probability of mating decreases with distance