Q1. Why are the birds discussed in this lab called Darwin\'s finches? Charles Darwin named them Geospiza leodarwini in honor of his son Leonard. They come from the Darwin archipelago off the coast of Ecuador. Charles Darwin collected the first scientific specimens. John Gould placed them in the genus Darwinospiza. Q2. A medium ground finch\'s ability to survive often depends on its beak size primarily because: Birds with bigger beaks are socially dominant and therefore get the best nest sites. Beak size determines which seeds a finch can eat and how efficiently it can eat them. Longer beaks make better weapons, which the birds use to defend themselves against predators. Larger-beaked finches experience higher mating success. Q3. Which statement best describes the pattern of natural selection on beak size? Deep beaks are favored in dry years, while shallow beaks are favored in wet years. Selection favors birds with bigger beaks. Selection favors birds with smaller beaks. Shallow beaks are favored in large populations, while deep beaks are favored in small populations. Q4. What can happen to our virtual finch population if the weather changes between wet and dry conditions too rapidly? The mutation rate may fall to zero. The distribution of beak sizes may cease to be bimodal. The finch population may go extinct. Beak size may cease to affect survival. Q5. What happened to beak depths in the virtual finch population when selection on beak depth was eliminated (selection strength = 0) and mutation rate for alleles determining beak depth was greater than zero? Average beak depth consistently increased. Average beak depth consistently decreased. The range in beak depths (largest to smallest) became larger. The range in beak depths became smaller. Q6. The Correlated Traits exercise shows that: When two characters are correlated, selection always favors larger values for both or smaller values for both. When two characters are correlated, one of them can evolve toward higher values even if smaller values are better for survival. When two characters are correlated, selection is always strong on both or weak on both. When two characters are correlated, the optimal values and selection strengths rise and fall together. Q7. In the Mountains and Valleys exercise, which of the following parameters had the largest influence on whether the finch population evolved a bimodal distribution? The speed at which the model ran. The difference in carrying capacity between the wet versus dry sides of the island. The number of chicks each pair of parents produced each year. How far the birds flew when looking for a mate. Q8. The final exercise, Large and Small Seeds, showed that: In the absence of geographic barriers, a population cannot evolve distinctive subpopulations. Bimodal distributions are more likely to evolve when geographic barriers are absent. Bimodal distributions only evolve when the population\'s food supply is divided into two types. Bimodal distributi.

1. Q1. Why are the birds discussed in this lab called Darwin's finches?
Charles Darwin named them Geospiza leodarwini in honor of his son Leonard.
They come from the Darwin archipelago off the coast of Ecuador.
Charles Darwin collected the first scientific specimens.
John Gould placed them in the genus Darwinospiza.
Q2. A medium ground finch's ability to survive often depends on its beak size primarily
because:
Birds with bigger beaks are socially dominant and therefore get the best nest sites.
Beak size determines which seeds a finch can eat and how efficiently it can eat them.
Longer beaks make better weapons, which the birds use to defend themselves against predators.
Larger-beaked finches experience higher mating success.
Q3. Which statement best describes the pattern of natural selection on beak size?
Deep beaks are favored in dry years, while shallow beaks are favored in wet years.
Selection favors birds with bigger beaks.
Selection favors birds with smaller beaks.
Shallow beaks are favored in large populations, while deep beaks are favored in small
populations.
Q4. What can happen to our virtual finch population if the weather changes between wet and dry
conditions too rapidly?
The mutation rate may fall to zero.
The distribution of beak sizes may cease to be bimodal.
The finch population may go extinct. Beak size may cease to affect survival.
Q5. What happened to beak depths in the virtual finch population when selection on beak depth
was eliminated (selection strength = 0) and mutation rate for alleles determining beak depth was
greater than zero?
Average beak depth consistently increased.
Average beak depth consistently decreased.
The range in beak depths (largest to smallest) became larger.
The range in beak depths became smaller.
Q6. The Correlated Traits exercise shows that:
When two characters are correlated, selection always favors larger values for both or smaller
values for both.
When two characters are correlated, one of them can evolve toward higher values even if smaller
values are better for survival.
When two characters are correlated, selection is always strong on both or weak on both.

2. When two characters are correlated, the optimal values and selection strengths rise and fall
together.
Q7. In the Mountains and Valleys exercise, which of the following parameters had the largest
influence on whether the finch population evolved a bimodal distribution?
The speed at which the model ran.
The difference in carrying capacity between the wet versus dry sides of the island.
The number of chicks each pair of parents produced each year.
How far the birds flew when looking for a mate.
Q8. The final exercise, Large and Small Seeds, showed that:
In the absence of geographic barriers, a population cannot evolve distinctive subpopulations.
Bimodal distributions are more likely to evolve when geographic barriers are absent.
Bimodal distributions only evolve when the population's food supply is divided into two types.
Bimodal distributions can evolve when geographic barriers are absent.
Q9. Under which of the following conditions is a population most likely to evolve a bimodal
distribution?
Selection favors multiple distinct trait values, and similar individuals tend to mate with each
other.
Traits are strongly correlated, and a low carrying capacity keeps the population size small.
Environmental conditions change rapidly, and a low mutation rate limits the establishment of
new variants.
Selection is weak, and individuals produce large numbers of offspring each generation.
Q10. In the lab, which of the following factors made it more likely that similar individuals would
mate with each other? Check all that apply:
Selectivity in choosing mates.
The availability of smaller seeds.
Geographic barriers separating subpopulations.
Long term weather patterns.
Solution
Q1.Charles Darwin collected the first scientific specimens.
Q2. Beak size determines which seeds a finch can eat and how efficiently it can eat them.
Q3. Deep beaks are favored in dry years, while shallow beaks are favored in wet years.
Q4. The distribution of beak sizes may cease to be bimodal.