Exam 22: Evolution by Natural Selection

Evolutionary theory predicts that species are related, not independent. Four of the following examples provide support for this prediction, but one is irrelevant. Which one of these examples does not support the claim that species are related?

Your text discusses the evolution of antibiotic- resistant M. tuberculosis bacteria in a patient. Researchers discovered that the strain of M. tuberculosis taken from the dead patient has a point mutation in the rpoB gene that codes for part of the RNA polymerase enzyme. This mutant form of RNA polymerase does not normally function as well as the more common form, but a commonly used antibiotic called rifampin does not affect the mutant rpoB. A researcher places M. tuberculosis isolated from the patient a year before death no rpoB mutation) in cell cultures with M. tuberculosis isolated from the dead patient with rpoB mutation). Half the cell cultures contain just standard nutrients, and the other cell cultures contain rifampin in addition to the standard nutrients. After many cell generations, the researcher finds that

According to the theory of evolution by natural selection, which of the following is FALSE?

Which of the following statements is an example of typological thinking?

A population of rabbits grows explosively because resources are high. However, now that numbers have increased substantially, there is not enough food for all individuals and the population is threatened. What will happen under such circumstances?

A population of beetles lives on a forest floor, which is covered in dark leaf litter. Dark beetles have the genotype A₂A₂, while lighter beetles have an A₁A₁ genotype; heterozygotes have a phenotype that is closer to that of the A₁A₁ homozygotes. The oppresso bird preys on these beetles. What outcome do you predict?

If you say that Squirrel A has greater biological fitness than Squirrel B, you mean that the animal

Radiometric dating is a technique used to determine the age of rocks. Geologists have used this technique to determine that

After the drought of 1977, researchers hypothesized that on Daphne Major, medium ground finches with large, deep beaks survived better than those with smaller beaks because they could more easily crack and eat the tough Tribulus cistoides fruits. If this hypothesis is true, what would you expect to observe if a population of these medium ground finches colonizes a nearby island where T. cistoides is the primary available food in all yea Assume that 1) even the survivors of the 1977 drought sometimes had difficulty cracking the tough T. cistoides fr and would eat other seeds when offered a choice, and 2) food availability is the primary limit on finch fitness on this new island.

Why was Darwin and Wallace's theory of evolution by natural selection revolutionary?

Which of the following is a fitness trade- off?

Which of these conditions are always true of populations evolving due to natural selection? Condition 1: The population must vary in traits that are heritable. Condition 2: Some heritable traits must increase reproductive success. Condition 3: Individuals pass on all traits they acquire during their lifetime.

Researchers have found fossils of Eocene horse species in Colorado. Deeper deposits contain smaller species, and more recent deposits contain larger species. How does this observation support the theory of evolution?

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. Slugs prefer to eat pink- flowering over white- flowering plants due to chemical differences between the two), and plants experiencing severe herbivory are more likely to die. The bees that pollinate this plant also prefer pink to white flowers, so that Claytonia with pink flowers have a greater relative fruit set than Claytonia with white flowers. A researcher observes that the percentage of different flower colours remains stable in the study population from year to year. If the researcher removes all slugs from the study population, what do you expect to happen to the distribution of flower colours in the population over time?

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, no matter how often he applies triazine. Which of these actions is most likely to solve the farmer's problem?

The following questions) are based on information in Hopi E. Hoekstra, Kristen E. Drumm, and Michael W. Nachman, "Ecological Genetics of Adaptive Color Polymorphism in Pocket Mice: Geographic Variation in Selected and Neutral Genes," Evolution 586), 2004: 1329- 41. Figure 22.1 -The figure above shows the distribution of pocket- mouse coat colours in several Arizona populations found either on light- coloured granite substrate or on dark volcanic rock dark substrate). The Melanocortin- 1 receptor Mc1r) alleles, D and d, differ by four amino acids. Mice with DD and Dd genotypes have dark coats, whereas mice with the dd genotype are light coloured. What sort of genotype frequencies might you expect to find in the Xmas, Mid, and O'Neill populations?

Why did Darwin argue that evidence of extinction supports the theory of evolution?

Figure 22.3 In Figure 22.3, chart X above shows the frequency of the most common neutral mitochondrial DNA allele an all gene that does not affect and is not linked to coat colour) across six pocket- mouse populations. Populations C, D and E live on dark volcanic rock; populations A, B, and F live on light- coloured granite. Compare this figure with chart Y above. What should you conclude after comparing these two figures?

Which statement about transitional features is true?

Which of the following is the best modern definition of evolution?