Question

1.A population of alpacas all have an identical fur length phenotype. During a particularly cold winter, longer fur would be beneficial as it would provide them with greater insulation. Select the correct answer given this information.

A. the alpacas will evolve by natural selection as longer hair would be favorable in their environment.

B. a mutation for longer fur will likely develop in this population.

c. alpacas will longer fur will likely migrate into this population as they have a beneficial phenotype for the cold winter environment.

d. the alpacas will not evolve by natural selection for fur length phenotype.

2.In our evolution case study, the bird population initially had three beak size phenotypes--small, medium, and large. Following the drought, you correctly predicted that the next generation would have exclusively large and medium beaked birds as the smallest food source had died out.

Which of the following accurately describes why there were no small beaked birds in the next generation?

a. the birds with small beaks mutated to have larger or medium beaks because that is more beneficial phenotype for the environment.

b. the small beaker bird died and thus didnt contribute alleles for small beaks to the next generation.

c.the small beaked birds migrated to an area with better food availability.

d. the small beaked bird died randomly.

3.In a population of fish, there is substantial variation in fin length phenotype. If a fish is raised in an environment with high predator pressure, that fish will develop a smaller tail at adulthood as long tails make them easier to catch. If a fish is raised in an environment with low predator pressure, that fish will develop a longer tail as greater length increases swimming speed and the threat of predators is low. Further, eggs from short tailed parents when raised with low predator pressure develop long tails. Eggs from long tailed parents when raised with high predator pressure develop short tails.

The tail length differences observed in this scenario are a product of evolutionary change by natural selection.

true/ false

4.Select all of the answers that correctly describe genetic drift.

a. a random evolutionary mechanism
b. results in adaptation
c. may or may not result in allele frequencies from generation to generation

d. does result in better adapted populations

5.A group of lady bugs has variation for spot number phenotype and this variation is genetically controlled. There is no relationship between spot number and any environmental pressure in the lady bug's environment. Roughly thirty percent of the population migrates away to a different location and allele frequencies substantially change in the population as a result of the migration. If the allele frequency changes are maintained in the next generation, select the answer that correctly describes this scenario.

a. the population has evolved by genetic flow
b.this population has evolved by genetic drift
c. this population has evolved by natural selection
d. this population has evolved by mutation

6. In the Phenotypes, Genes, and the Environment lecture, we evaluated phenotypic variation in 4 hypothetical bug populations. This question pertains to those 4 hypothetical populations and you will need to view them to answer this question successfully. Select the answer that correctly describes why this was the correct choice.

a. population   2 has no phenotypic variation so Vg was also 0
b. population 2 had some environmental variation affecting phenotypic variation so Vg had to be 0 because there environmental effects.
c. all of the individuals in population 2 were genetically identical and thus no phenotypic variation could be explained by genotypic   variation.
d. although population 2 had some genotypic variation, it had less than the other populations.

7.In the Phenotypes, Genes, and the Environment lecture, we evaluated phenotypic variation in 4 hypothetical bug populations. This question pertains to those 4 hypothetical populations and you will need to view them to answer this question successfully. Please find the appropriate slide before attempting this question. The full slide set as of 5.19.2020 has been posted in the modules section.

We determined that Ve was lowest in population 4. Select the answer that correctly describes why this was the correct choice.
a. There is no phenotypic variation in this population and thus Ve is also 0.

b. The individuals in this population are not experiencing any environmental variation and thus no phenotypic variation is explained by environmental effects.

c. This population has a relatively high genotypic diversity and thus environmental effects must be minimal.

8. In the Phenotypes, Genes, and the Environment lecture, we evaluated phenotypic variation in 4 hypothetical bug populations. This question pertains to those 4 hypothetical populations and you will need to view them to answer this question successfully. Please find the appropriate slide before attempting this question. The full slide set as of 5.19.2020 has been posted in the modules section.
We determined that all four population had Vp > 0. We also know that population 2 has Vg = 0 and population 4 has Ve = 0. Select the answers that correctly describe the relationship between Vp, Ve, and Vg.

a.Vp can be greater than 0 even if both Ve and Vg in a population are 0.

b.Vp describes total phenotypic variation in a population irrespective of whether that variation has environmental or genetic causes.

c.As long as Ve OR Vg are greater than 0, Vp will also be greater than 0.

9. In the Phenotypes, Genes, and the Environment lecture, we evaluated phenotypic variation in 4 hypothetical bug populations. This question pertains to those 4 hypothetical populations and you will need to view them to answer this question successfully. Please find the appropriate slide before attempting this question. The full slide set as of 5.19.2020 has been posted in the modules section.
We determined that Population 2 could not evolve by natural selection. If this population has phenotypic variation, why could it not experience natural selection for this trait? Select all that apply.

a.It could evolve by natural selection if a relevant environmental pressure that favored lighter or darker individuals occurred.

b.The phenotypic variation was due to environmental effects.

c.The individuals in the population were all genotypically identical so the variation was not genetically determined.

d.A population with phenotypic variation can always potentially evolve for that characteristic.

10 . A group of scientists wants to determine if fin length variation is genetically or environmentally controlled. They think the presence of predator pressure may be an environmental determinant of fin length.
The scientists take eggs from short-tailed parents and raise them in both low and high predator pressure environments. They also take eggs from long-tailed parents raise them in both low and high predator pressure environments. The scientists then evaluate the tail length of the fish hatched from the eggs at adulthood.
Select the correct dependent variable for this experiment.

a.Level of predation pressure.

b.Tail length at adulthood.

c.Tail length of the parents of the eggs.

d.The eggs.

Answer 1

1) A, Natural election is selection of most favourable character in any environment. so,the alpacas will evolve by natural selection as longer hair would be favorable in their environment.

2) B, There is not even 1 number of short beaks in the next generation because all the birds died due to hunger. So the answer is, the small beaker bird died and thus didnt contribute alleles for small beaks to the next generation.

3) True , In this case tail length is adaptation to environment and naturaly select only those tail length which is favourable to environment and pass to next generation .

4) a,Genetic drift is a random evolutionary mechanism and change frequency of alleles in the population.