Understanding Darwin's Tree of Life - Bio Test 1 Questions

Which of the following phrases complete the following statement? Choose all that apply.
In the video, we watched a dramatization of Darwin drawing the figure below, that was famously taken from one of Darwin's travel journals. If this drawing were expanded into a vast branching tree of historical relationships for all known species that live or ever have lived, that tree would:
A.
depict how the evolutionary history of life on Earth resulted in the current diversity we see today.
B.
be a map that reflects the process of new species descending with modifications from past species.
C.
Both A and B

One of the basic ideas in the theory of evolution is that the more characteristics that are shared by two species:

Darwin's theory of descent with modification predicts that a region's current plants and animals will be most similar to fossils

The development of antibiotic resistance is the result of:

How did Darwin describe evolution?

Under the theory of evolution by Darwin How did the long legged lizard change when they were move to an environment that favor short legs.

If there is NO VARIATION in shell thickness within a population of snails, and no mutations occur, what happens to shell thickness in response to crab predation?
A. All snails in the population grow thicker shells.
B. Some snails in the population evolve thicker shells.
C. The average shell thickness evolves to be much thicker over several generations.
D. There is no change in shell thickness within the population.

If there is NO SELECTIVE SURVIVAL based on shell thickness within a population of snails, what happens to shell thickness in response to crab predation?
A. The average shell thickness increases within each generation, but there is no change in shell thickness from generation to generation.
B. There is evolution by natural selection of shell thickness, and average shell thickness increases every generation.
C. There may be evolution of shell thickness, but not through natural selection and not necessarily toward thicker shells.
D. There is no change in shell thickness within the population.

If mutations arise that affect shell thickness within a snail population, then with crabs present, those mutations:
A. Will result in offspring having thicker shells than their parents.
B. Will result in offspring having thicker or thinner shells than their parents.
C. Will happen because the parents choose to give them to their offspring.
D. Will occur because crabs are present and snails need protection against predation.

The 14 species of finches on the Galapagos Islands evolved from a single species that migrated to the islands several million years ago. Different finch species live on different islands. A major difference among finch species is in their beaks: both size and shape vary greatly.
Assume that a population of one of these finch species is undergoing evolution by natural selection with respect to beak size and shape. What changes occur gradually over time that indicate the population is evolving?
A.
Within their lifetimes, some individual finches' beaks change in size or shape.
B.
The proportions of finches having different beak sizes/shapes change across generations.
C.
Each finch's learned ability to use its beak is automatically passed on to its offspring.
D.
All finches in each new generation develop the same new, improved beak size and shape.

Could individuals of a species look different today than individuals of the same species did many generations ago? Why or why not?
A. Yes, all individuals can change a little and pass those changes on to their offspring.
B. Yes, some individuals can change a little and pass those changes on to their offspring.
C. Yes, some individuals with certain traits are more likely to survive and pass those traits on to their offspring.
D. No, species do not change even after many generations, so individuals of the same species would not look different.

Ducks are aquatic birds. Their feet are webbed and this trait makes them fast swimmers. Biologists believe that ducks evolved from land birds that did not have webbed feet. The amount of webbing on a duck's feet is a heritable trait.
While webbed feet were evolving in ancestral ducks, with each generation:

DDT is an insecticide that was used extensively in the mid-1900s to kill mosquitoes. It was very effective at first, but after a few decades DDT became less effective at killing mosquitoes because many populations had evolved resistance to DDT. Which of the following conditions would biologists say was REQUIRED for the evolution of DDT resistance in a population?
A. A few mosquitoes in the population were resistant to DDT before it was ever used.
B. Mosquitoes in the population learned to adapt to the high levels of DDT in the environment.
C. The mosquito population needed to evolve DDT resistance in order to avoid extinction.
D. Exposure to DDT caused specific, nonrandom mutations for DDT resistance within the population.

Consider the following hypothetical scenario: An ancestral species of duck had a varied diet that included aquatic plants and terrestrial plants and insects. These ducks spent time on both land and water. Individuals of this species varied in the amount of webbing in their feet, with some individuals having more webbing and some having less. As many years went by, the environment changed such that the aquatic food sources were much more plentiful than those on land. Many generations later, almost all ducks had more webbing on their feet. How is this best explained?
A. Ducks with less webbing worked harder than ducks with more webbing to eat aquatic plants. The more they used their feet, the more webbed their feet became, so they got enough food to survive and reproduce.
B. Due to chance mutations, all the ducks' feet in the next generation had more webbing. They were therefore able to eat aquatic plants and get enough food to survive and reproduce.
C. Ducks with more webbing were better at eating aquatic plants than ducks with less webbing, so the ducks with more webbing survived and reproduced better than ducks with less webbing.
D. Ducks with less webbing needed to grow more webbing in their feet in order to improve their access to aquatic plants, which allowed them to survive better and reproduce more.

What is a most recent common ancestor?

What is a clade/monophyletic group?

What is a paraphyletic group?

A large sunflower population is established in a field. The flowers mate randomly, and all individuals are equally likely to survive and reproduce. In this population, 80% of the alleles of a gene for petal color are dominant and 20% of the alleles are recessive. Given this information, after many generations, which of the following options would be most likely?

A.

The allele frequencies will be 100% dominant and 0% recessive.

B.

The allele frequencies will be 80% dominant and 20% recessive.

C.

The allele frequencies will be 60% dominant and 40% recessive.

A lizard population has two alleles for horn length. Long horns help protect the lizard from predation by birds. Homozygotes with allele 1 have long horns, while homozygotes with allele 2 have short horns. Given this information, which of the following is most likely true about the mode of inheritance for allele 1, and why?
A. Allele 1 is dominant, because it gives lizards an advantage.
B. Allele 1 is recessive, because it gives lizards an advantage.
C. Alleles 1 and 2 are codominant, because each codes for a different horn length.
D. It is impossible to say, because dominance cannot be inferred from fitness.

The allele for black noses in wolves is dominant over the allele for brown noses. There is no known selective advantage for one nose color over another in wolves. If this remains true, which of the following statements is most likely TRUE about the change in wolf nose colors over many generations?
A. Black noses will become more common than they are now.
B. Black noses will stay about the same frequency as now.
C. Black noses will become less common than they are now.
D. Brown noses will disappear after enough generations pass.

A large population of land turtles on an isolated island has two alleles for a gene that determines shell thickness. The allele for thinner shells is dominant over the allele for thicker shells. The thinner-shell allele occurs at a frequency of 20%. Assuming there is no net advantage to thick or thin shells, what should the frequency of homozygous thicker-shelled turtles be in the population?

A.4%

B.16%

C. 50%

D. 64%

If the frequency of the S (sickled) allele at the hemoglobin locus is 0.3 in a population, what is the frequency of the A (normal) allele (assuming this is a locus with only 2 alleles)?

Which of the following would be sufficient for the Hardy-Weinberg equation to accurately predict genotype frequencies from allele frequencies?
A. p+q=1
B. The population is not evolving due to natural selection.
C. The population is not evolving due to any of the conditions that disrupt Hardy-Weinberg equilibrium.
D. The population is infinitely large.

In a village, if the proportion of individuals who have sickle-cell disease is 0.40, and the population is assumed to be at Hardy-Weinberg equilibrium, what is the expected frequency of the S (sickled) allele?

In a village where the proportion of individuals who are susceptible to malaria (genotype AA) is 0.70, and the population is assumed to be at Hardy-Weinberg equilibrium, what proportion of the population should be heterozygous (genotype AS)?

Which of the following is FALSE?
A. If a genetic disease reduces fertility and the allele that causes the disease offers no other advantage, the allele will likely eventually disappear, due to natural selection.
B. Natural selection does not favor individuals who are homozygous for the sickle-cell allele, because these individuals typically die before they are old enough to reproduce.
C. Individuals who are heterozygous HbA/HbS are protected from malaria, and this is why sickle-cell disease persists in wetter, mosquito-prone regions in Africa.
D. In regions where malaria does not occur, individuals who are heterozygous HbA/HbS have a fitness advantage over those who are homozygous for the normal hemoglobin allele (HbA).