Exam 22: Evolution by Natural Selection

Figure 22.2 The distribution of pocket- mouse coat colours in several Arizona populations is associated with substrate colour Some populations live on light- coloured granite substrate, and others live on dark volcanic rock. In Figure 22.2, chart A shows the frequency of the melanic dark) coat phenotype across six populations. Populations C, D, and E live on dark volcanic rock; populations A, B, and F live on light- coloured granite. Chart B shows the Frequency of the Melanocortin- 1 receptor Mc1r) allele across these populations. The Mc1r alleles, D and d, differ by four amino acids; mice with DD and Dd genotypes have dark coats, whereas mice with dd genotype are light coloured. Which of the following statements best interprets the results shown in charts A and B?

Who proposed that organisms could be organized into a great chain of being?

Which of the following scientists argued that variation among individuals allows evolution to occur?

Which of the following is an example of acclimation?

A farmer uses triazine herbicide to control pigweed in his field. For the first few years, the triazine works well and almost all the pigweed dies; but after several years, the farmer sees more and more pigweed. Which of these explanations best describes this observation?

Explain how one of the following supports the idea that species change through time: artificial selection, extinction, transitional forms, vestigial traits, or antibiotic resistance.

Parasitic species tend to have simple morphologies. Which of the following statements best explains this observation?

Use the following information when answering the corresponding questions). The following questions) are based on information from Frank M. Frey, "Opposing Natural Selection from Herbivores and Pa May Maintain Floral- Color Variation in Claytonia virginica Portulacaceae)," Evolution 5811), 2004: 2426- 37. -Claytonia virginica is a woodland spring herb with flowers that vary from white to pale pink to bright pink. This plant is primarily pollinated by a bee that prefers pink flowers to white flowers. Claytonia with pink flowers have a greater relative fruit set than Claytonia with white flowers. Nevertheless, the percentage of different flower colours remains stable in the study population from year to year. Which of these statements might explain this observation?

Evolution by natural selection changes the population but not the individual.

Fishers typically target the largest, and thus, oldest fish. Given this fishing strategy, which of the following would be the most likely outcome due to natural selection over time on life history traits. Which of the following best predicts the effect of natural selection due to this fishing strategy on the life history traits of the commercially popular fish?

Tourist companies start visiting Island X, where the new colony of medium ground finches see previous question) feeds on the tough- fruited Tribulus cistoides. The tourist companies set up reliable feeding stations with a variety of bird seeds different types and sizes), so that tourists can get a better look at the finches. Which of these events is now most likely to occur to finch beaks on Island X?

The same basic internal organs kidneys, stomach, heart, lungs) are found in frogs, birds, snakes. and rodents. This is primarily an example of

Which of the following is an example of an environmental constraint on evolution by natural selection?

This scenario is for the next questions). You have a mixed population of bacteria S. aureus) in the lab. Approximately half of them WT) are susceptible to the antibiot rifampin. The other half are not, due to a mutation in the rpoB gene. The rpoB mutation results in an RNA polymerase that doesn't work as well as in the WT, hence transcription is not as rapid, and these bacteria grow much more slowly than those with the WT enzyme. -If the population is maintained on media that contains rifampin, what is expected to occur over a period of time?

Vestigial traits and neutral changes in DNA sequences are good examples of

Which of the following statements describes a vestigial trait?

You sequence the genes that code for an important glycolytic enzyme in a moth, a mushroom, a worm, and an alga, and find a high degree of sequence similarity among these distantly related species. This is an example of

Evolution of antibiotic resistant bacteria represents which of the following?

Gill pouches in chick, human, and house- cat embryos are an example of

Read the scenario above. If the population is maintained on media that lacks rifampin, what is expected to occur over a period of time?