Exam 2

Question 1

Speciation is a form of

Answer 1

macroevolution

Question 2

Which evolutionary effect would be most likely to occur if a small part of a population relocated to a new area?

Answer 2

The founder effect

Question 3

The insecticide DDT is used to control mosquitoes that carry malaria; however, some mosquito populations are now resistant to DDT because of

Answer 3

Artificial selection

Question 4

Which process will decrease the magnitude of phenotypic variation between generations?

Answer 4

Stabalizing selection

Question 5

The primary difference between artificial selection and natural selection is

Answer 5

natural selection only selects for traits that increase fitness

Question 6

What is the assumption used when arranging species on a phylogenetic tree?

Answer 6

Organisms with the most traits in common are the most closely related.

Question 7

Why does evolution require that traits be inherited?

Answer 7

Increased fitness must be passed on to offspring.

Question 8

What is not a primary source of genetic variation?

Answer 8

genetic drift

sexual reproduction is, mutation is, recombination is.

Question 9

The difference between the processes involved in allopatric speciation and sympatric speciation is:

Answer 9

allopatric speciation requires geographic isolation.

Question 10

What is the relationship between genes and alleles?

Answer 10

alleles are different forms of a particular gene

Question 11

Which is not a common environmental cue?

Answer 11

Population size

Question 12

Two reasons for trade-off between offspring size and offspring number are:

Answer 12

physical limitations and nutrient availability

Question 13

Which would you expect from an organism with low annual survival?

Answer 13

reproduction beginning at an early age

Question 14

Why do some species of plants flower earlier in warmer spring temperatures when other spring plants do not?

Answer 14

The plants that flower earlier are more sensitive to temperature.

Question 15

An organism that only reproduces once is known as:

Answer 15

semelparous

Question 16

Why might natural selection act more strongly on traits that improve reproductive success early in life rather than later in life?

Answer 16

Many organisms do not survive to reach the age where the traits increase survival

Question 17

Why might an increased number of offspring with higher parental care be selected against?

Answer 17

Increased parental care can decrease the subsequent fitness of the parent.

Question 18

Using Grimes categorization, which method of dispersal would be expected from ruderals?

Answer 18

wind-dispersed seeds

Question 19

All of the following explain why trade-offs among life history traits are common EXCEPT

Answer 19

the lack of constant environments

Question 20

Why do organisms face a trade-off between growth and fecundity?

Answer 20

limited energy

Question 21

The benefits of sexual reproduction include:

Answer 21

purging of mutations

Question 22

Extra-pair copulation had favored the development of

Answer 22

mate guarding

Question 23

Why does the less common sex in a population have a higher fitness?

Answer 23

Members contribute more genes on average per offspring

Question 24

Why might exaggerated secondary sexual characteristics in males demonstrate a superior genotype to females?

Answer 24

They often reduce fitness, which signifies a better genotype for survival.

Question 25

Which does local mate competition favor?

Answer 25

A female-biased offspring ratio

Question 26

When might environmental sex determination be an adaptive strategy?

Answer 26

When offspring of each gender can survive better in different conditions

Question 27

Given that self-fertilization can lead to inbreeding depression, under what conditions should a hermaphrodite use self-fertilization?

Answer 27

When population density is low

Question 28

Which mating system is favored when the males can make important contributions to raising the offspring?

Answer 28

monogamy

Question 29

The Red Queen hypothesis states that

Answer 29

sexual reproduction can increase resistance to parasites

Question 30

When the fitness increment of increased male function results in a larger cost in fitness through female function

Answer 30

Hermaphrodites will have a fitness advantage

Question 31

How does a haplodiploid sex-determination system favor the evolution of eusociality?

Answer 31

It increases the relatedness of the group.

Question 32

How does relatedness in the immediate families of haplodiploid organisms and diploid organisms differ?

Answer 32

In haplodiploid organisms brothers and sisters are less closely related than in diploid organisms.

Question 33

Why are selfish behaviors less favored when the donor and recipient are related to each other?

Answer 33

They cause an indirect reduction in fitness for the donor.

Question 34

What species is evidence that a haplodiploid sex-determination system is not required for the evolution of eusociality?

Answer 34

mole rats

Question 35

Which behavior reduces the fitness of both the donor and recipient?

Answer 35

spitefulness

Question 36

The dilution effect refers to

Answer 36

the reduced probability that any single animal in a group will be caught by a predator

Question 37

Under what conditions would natural selection favor living in large groups?

Answer 37

in a species that hunts large animals

Question 38

How could helping a relative improve fitness?

Answer 38

The relative will pass on the helper’s genes

Question 39

Why might individuals give up defending their territories if the population density increases?

Answer 39

Due to the increased difficulty of defending the territory

Question 40

What is the coefficient of relatedness for the offspring of an individual?

Answer 40

0.5