science

Question 1

What is evolutionary fitness?

Answer 1

a measure of an organism’s ability to survive and reproduce in a specific environment, ultimately defined by how successfully it passes its genes to the next generation

Question 2

what does natural selection act on?

Answer 2

the phenotypes (physical traits/characteristics) of individuals within a population.

Question 3

what does evolution act on?

Answer 3

the genetic variation within populations,

Question 4

Identify the three ways natural selection affects the distributions of phenotypes.

Answer 4

directional, stabilizing, and disruptive selection

Question 5

What is stabilizing selection? What is the example given in the book?

Answer 5

a type of natural selection that favors average, intermediate phenotypes rather than extreme variations, reducing genetic diversity in a population

Question 6

What is disruptive selection?

Answer 6

a type of natural selection that favors extreme phenotypes over intermediate ones, causing the population to diverge into two distinct groups.

Question 7

Define genetic drift. What type of populations does it typically occur in?

Answer 7

a population due to random chance, rather than natural selection. It causes unpredictable fluctuations in allele frequencies, potentially leading to the loss of genetic variations or the fixation of alleles.

Question 8

Define the Founder Effect

Answer 8

a type of genetic drift occurring when a small, unrepresentative sample of a population establishes a new, isolated colony.

Question 9

Define the Hardy-Weinberg principle. What condition does it describe?

Answer 9

a population’s allele and genotype frequencies will remain constant—meaning the population is not evolving—from generation to generation in the absence of other evolutionary influences

Question 10

When does genetic equilibrium occur?

Answer 10

allele and genotype frequencies in a population remain constant from generation to generation,

Question 11

What are the five conditions that need to be met in order for there to be a genetic equilibrium?

Answer 11

no mutations, random mating, no natural selection, extremely large population size, and no gene flow (immigration/emigration)