Exam 19: Descent With Modification

During a study session about evolution, one of your fellow students remarks, "The giraffe stretched its neck while reaching for higher leaves; its offspring inherited longer necks as a result." Which statement is most likely to be helpful in correcting this student's misconception?

Lamarck's contribution to evolutionary theory was the

Analogous features share ________ function but not ________ ancestry.

What is an example of what happens when herbivores switch to a new food source with different characteristics?

Which of the following is the most accurate summary of Cuvier's consideration of fossils found in the vicinity of Paris?

The rise of methicillin-resistant Staphylococcus aureus (MRSA) can be considered to be an example of artificial selection because

What is true of pseudogenes?

Figure 19.1 -Figure 19.1 shows an outcrop of sedimentary rock whose strata are labeled A-D. If x indicates the location of fossils of two closely related species, then fossils of their most-recent common ancestor are most likely to occur in which stratum?

Natural selection is based on all of the following except

Over evolutionary time, many cave-dwelling organisms have lost their eyes. Tapeworms have lost their digestive systems. Whales have lost their hind limbs. How can natural selection account for these losses?

Currently, two extant elephant species (X and Y) are placed in the genus Loxodonta, and a third species (Z) is placed in the genus Elephas. Thus, which of the following statements is true?

Please use the following information to answer the question(s) below. The following questions refer to the evolutionary tree below. The horizontal axis of the cladogram depicted below is a timeline that extends from 100,000 years ago to the present; the vertical axis represents nothing in particular. The labeled branch points on the tree (V-Z) represent various common ancestors. Let's say that only since 50,000 years ago has there been enough variation between the lineages depicted here to separate them into distinct species, and only the tips of the lineages on this tree represent distinct species. Figure 19.2 -Which pair would probably have agreed with the process that is depicted by this tree?

Darwin's observation of the Galápagos Islands finches' various beaks and behaviors could be explained by

What are adaptations?

Within six months of effectively using methicillin to treat S. aureus infections in a community, all new S. aureus infections were caused by MRSA. How can this best be explained?

Given a population that contains genetic variation, what is the correct sequence of the following events, under the influence of natural selection? 1) Well-adapted individuals leave more offspring than do poorly adapted individuals. 2) A change occurs in the environment. 3) Genetic frequencies within the population change. 4) Poorly adapted individuals have decreased survivorship.

Which of the following is not an observation or inference on which natural selection is based?

Figure 19.1 -Currently, two extant elephant species (X and Y) are placed in the genus Loxodonta, and a third species (Z) is placed in the genus Elephas. Assuming this classification reflects evolutionary relatedness, which of the following is the most accurate phylogenetic tree?

Please use the following information to answer the question(s) below. The following questions refer to the evolutionary tree below. The horizontal axis of the cladogram depicted below is a timeline that extends from 100,000 years ago to the present; the vertical axis represents nothing in particular. The labeled branch points on the tree (V-Z) represent various common ancestors. Let's say that only since 50,000 years ago has there been enough variation between the lineages depicted here to separate them into distinct species, and only the tips of the lineages on this tree represent distinct species. Figure 19.2 -How many separate species, both extant and extinct, are depicted in this tree?

Which of the following must exist in a population before natural selection can act upon that population?