Evolution

Question 1

Evolution

Answer 1

descent with modification; changes in heritable traits from generation to generation
- Changes in allele frequencies from one generation to the next

Question 2

Who shaped modern evolutionary theory due to time he spent on the Galapagos Islands

Answer 2

Charles Darwin

Question 3

What was his book called (short name)

Answer 3

On the Origin of Species (or, more completely, On the Origin of Species by Means of Natural Selection, or the Preservation of Favored Races in the Struggle for Life)

Question 4

Individuals or populations

Answer 4

populations rather than individuals; meaning the changes in traits over time are observed across a group of organisms, not within a single individual

Question 5

5 factors that change allele frequencies over time

Answer 5

(1) natural selection
(2) mutation
(3) genetic drift
(4) nonrandom mating
(5) migration

Question 6

Artificial selection

Answer 6

Artificial selection (aka selective breeding): human chooses desired features, then
allows only the individuals that best express those qualities to reproduce

Question 7

Natural selection

Answer 7

Natural selection: environmental factors cause the differential reproductive success of individuals with particular genotypes

Question 8

3 modes of natural selection – compare

Answer 8

Directional selection: one phenotype is favored over another
Disruptive selection: extreme phenotypes are favored over an intermediate phenotype
Stabilizing selection: an intermediate phenotype is favored over the extreme phenotypes

Question 9

Does natural selection create new alleles or are the beneficial alleles/mutations/etc. already there

Answer 9

Natural selection doesn’t create new alleles. It strongly selects for camouflage alleles that arise by chance, natural selection operates on variation already present in the population

Question 10

Hardy-Weinberg equilibrium

Answer 10

unlikely situation in which allele frequencies don’t change between generations

Question 11

Assumptions that need to be met for equilibrium to occur

Answer 11

(1) natural selection does not occur
(2) no mutations
(3) the population is large enough to eliminate
random changes in allele frequencies
(4) individuals’ mate at random
(5) no migration

Question 12

Is it a common occurrence

Answer 12

no

Question 13

Equations that represent relationship between allele and genotype frequencies

Answer 13

p + q = 1, 100% of the alleles of that gene in a population
p^2 + 2pq + q^2, 100% of the individuals in that population

Question 14

p

Answer 14

frequency of the dominant allele

Question 15

q

Answer 15

frequency of the recessive allele

Question 16

Genetic drift

Answer 16

occurs purely by chance; most
common in small populations

Question 17

Founder effect

Answer 17

when only a few individuals establish a
new population, allele frequencies may change

Question 18

Bottleneck

Answer 18

occurs if a disaster drastically reduces
the size of a population