BIO 102 Chapter 25

Darwin and Wallace's theory of evolution by natural selection was revolutionary because it _____. A) dismissed the idea that species are constant and emphasized the importance of variation and change in populations B) proved that individuals acclimated to their environment over time C) was the first time a biologist had proposed that species changed through time D) was the first theory to refute the ideas of special creation

Which of the following is the best modern definition of evolution? A) survival of the fittest B) inheritance of acquired characters C) change in the number of genes in a population over time D) descent with modification

Of the following anatomical structures, which is homologous to the bones in the wing of a bird? A) cartilage in the dorsal fin of a shark B) bony rays in the tail fin of a flying fish C) bones in the hind limb of a kangaroo D) chitinous struts in the wing of a butterfly E) bones in the flipper of a whale

Which of the following evidence most strongly supports the common origin of all life on Earth? All organisms _____. A) use essentially the same genetic code B) show heritable variation C) reproduce D) require energy E) evolve

About thirteen different species of finches inhabit the Galápagos Islands today, all descendants of a common ancestor from the South American mainland that arrived a few million years ago. Genetically, there are four distinct lineages, but the thirteen species are currently classified among three genera. The first lineage to diverge from the ancestral lineage was the warbler finch (genus Certhidea). Next to diverge was the vegetarian finch (genus Camarhynchus), followed by five tree finch species (also in genus Camarhynchus) and six ground finch species (genus Geospiza). If the six ground finch species have evolved most recently, then which of these is the most logical prediction? A) They should be limited to the six islands that most recently emerged from the sea. B) The chances of hybridization between two ground finch species should be less than the chances of hybridization between two tree finch species. C) Their genomes should be more similar to each other than are the genomes of the five tree finch species. D) They should share fewer anatomical homologies with each other than they share with the tree finches.

Logically, which of these should cast the most doubt on the relationships depicted by an evolutionary tree? A) Relationships between DNA sequences among the species did not match relationships between skeletal patterns. B) Some of the organisms depicted by the tree had lived in different habitats. C) Transitional fossils had not been found. D) The skeletal remains of the organisms depicted by the tree were incomplete (in other words, some bones were missing). E) None of the organisms depicted by the tree ate the same foods.

Fossils of Thrinaxodon, a species that lived during the Triassic period, have been found in both South Africa and Antarctica. Thrinaxodon had a reptile-like skeleton and laid eggs, but small depressions on the front of its skull suggest it had whiskers and, therefore, fur. Thrinaxodon may have been warm-blooded. The fossils of Thrinaxodon are consistent with the hypothesis that _____. A) the environment where it lived was very warm B) Antarctica and South Africa separated after Thrinaxodon went extinct C) mammals evolved from a reptilian ancestor D) fossils found in a given area look like the modern species in that same area

The Irish "elk" described by Georges Cuvier suggests that _____. A) organisms could not have originated by special creation B) the great flood or some other catastrophe caused the evolution of new species C) the Earth is old enough for evolution to have occurred D) organisms could go extinct

Many crustaceans (for example, lobsters, shrimp, and crayfish) use their tails to swim, but crabs have reduced tails that curl under their shells and are not used in swimming. This is an example of _____. A) a vestigial trait B) a homologous structure C) natural selection D) convergent evolution

Which of the following, if discovered, could refute our current understanding of the pattern of evolution? A) radioactive dating of rocks showing that rocks closer to the Earth's surface are younger than lower rock strata B) diverse fossils of mammals in Precambrian rock C) no fossils of soft-bodied animals D) a modern bird having reptile-like scales on its legs

Similar gill pouches in embryos of a chick, human, and cat are an example of _____. A) developmental homology B) the inheritance of acquired characters C) structural homology D) genetic homology

The same basic internal organs (kidneys, stomach, heart, lungs) are found in frogs, birds, snakes, and rodents. This is primarily an example of _____. A) structural homology B) developmental homology C) inheritance of acquired characteristics D) genetic correlation

What must be true of any organ described as vestigial? A) It must be analogous to some feature in an ancestor. B) It must be homologous to some feature in an ancestor. C) It need be neither homologous nor analogous to some feature in an ancestor. D) It must be both homologous and analogous to some feature in an ancestor

One morphological feature of modern cetaceans is a vestigial pelvic girdle. If it is determined that the cetacean lineage diverged from the artiodactyls' lineage after the divergence of pigs and other artiodactyla, then the vestigial pelvic girdle of cetaceans should be considered a shared _____. A) ancestral character of the cetartiodactyls B) ancestral character of the cetaceans C) derived character of the cetaceans D) derived character of the cetartiodactyls

Which of the following is the best modern definition of evolution? A) survival of the fittest B) descent with modification C) inheritance of acquired characters D) change in the number of genes in a population over time

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. A) 2 → 4 → 1 → 3 B) 2 → 4 → 3 → 1 C) 4 → 1 → 2 → 3 D) 4 → 2 → 3 → 1 E) 4 → 2 → 1 → 3

Cotton-topped tamarins are small primates with tufts of long white hair on their heads. While studying these creatures, you notice that males with longer hair get more opportunities to mate and father more offspring. To test the hypothesis that having longer hair is adaptive in these males, you should _____. A) determine if hair length is heritable B) test whether other traits in these males are also adaptive C) look for evidence of hair in ancestors of tamarins D) test whether males with shaved heads are still able to mate

There is a population of beetles that typically have black wings. A scientist studying these beetles knows that their eggs hatch in early spring, the young insects grow through the late spring and summer, they lay eggs in the early fall, and they die in the early winter. Recently some beetles have been born with white wings. Early in life, the black- and white-winged beetles seem to be very similar in number of mating events, eggs laid, and survival rates, but shortly after laying their eggs the white beetles die and there are only black-winged beetles during the late fall. Which of the following is a true statement about the beetles? A) White wings are an adaptation. B) Black-winged beetles have a higher fitness than white-winged beetles. C) White- and black-winged beetles have equal fitness. D) The number of baby white-winged beetles will decrease in frequency 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. Which of these explanations best explains what happened? A) Triazine-resistant pigweed has less-efficient photosynthesis metabolism. B) The herbicide company lost its triazine formula and started selling poor-quality triazine. C) Triazine-resistant weeds were more likely to survive and reproduce. D) Natural selection caused the pigweed to mutate, creating a new triazine-resistant species

After the drought of 1977, researchers on the island of Daphne Major hypothesized that medium ground finches that had 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 correct, what would you expect to observe if a population of these medium ground finches colonizes a nearby island where Tribulus cistoides is the most abundant food for the next 1000 years? Assume that (1) even the survivors of the 1977 drought sometimes had difficulty cracking the tough T. cistoides fruits and would eat other seeds when offered a choice; and (2) food availability is the primary limit on finch fitness on this new island. A) evolution of yet larger, deeper beaks over time B) no change in beak size and shape C) random fluctuations in beak size and shape D) evolution of smaller, pointier beaks over time

After the drought of 1977, researchers hypothesized that on the Galápagos island 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. A tourist company sets 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 this island? A) no change in beak size and shape over time B) evolution of smaller, pointier beaks over time, until all birds have relatively small, pointy beaks C) evolution of yet larger, deeper beaks over time, until all birds have relatively large, deep beaks D) increased variation in beak size and shape over time

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 greater relative fruit set than Claytonia with white flowers. A researcher observes that the percentage of different flower colors remains stable in the study population from year to year. Given no other information, if the researcher removes all slugs from the study population, what do you expect to happen to the distribution of flower colors in the population over time? A) The percentage of white flowers should increase over time. B) The percentage of pink flowers should increase over time. C) The distribution of flower colors should randomly fluctuate over time. D) The distribution of flower colors should not change.

The figure above shows the distribution of pocket-mouse coat colors in several Arizona populations found either on light-colored 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 colored. What sort of genotype frequencies might you expect to find in the Xmas, Mid, and O'Neill populations? A) Xmas-high Dd frequency; Mid-high dd frequency, O'Neill-high DD frequency B) Xmas-high Dd frequency; Mid-high DD frequency, O'Neill-high dd frequency C) Xmas-high dd frequency; Mid-high DD frequency, O'Neill-high Dd frequency D) Xmas-high DD frequency; Mid-high Dd frequency, O'Neill-high dd frequency E) Xmas-high dd frequency; Mid-high Dd frequency, O'Neill-high DD frequency

DDT was once considered a "silver bullet" that would permanently eradicate insect pests. Instead, DDT is largely useless against many insects. Which of these would have prevented this evolution of DDT resistance in insect pests? A) DDT application should have been continual. B) All habitats should have received applications of DDT at about the same time. C) The frequency of DDT application should have been higher. D) None of the insect pests would have genetic variations that resulted in DDT resistance. E) Larger doses of DDT should have been applied from the air, into water, and within the soil.

If the bacterium Staphylococcus aureus experiences a cost for maintaining one or more antibiotic-resistance genes, what would happen in environments that lack antibiotics? A) These genes would be maintained in case the antibiotics appear. B) The number of genes conveying antibiotic resistance would increase in these bacteria. C) These bacteria would be outcompeted and replaced by bacteria that have lost these genes. D) These bacteria would try to make the cost worthwhile by locating and migrating to microenvironments where traces of antibiotics are present.

Which statement about the beak size of finches on the island of Daphne Major during prolonged drought is true? A) Each bird that survived the drought produced only offspring with deeper, stronger beaks than seen in the previous generation. B) Each bird's survival was strongly influenced by the depth and strength of its beak as the drought persisted. C) The frequency of the strong-beak alleles increased in each bird as the drought persisted. D) Each bird evolved a deeper, stronger beak as the drought persisted.

Vestigial traits and neutral changes in DNA sequences are good examples of _____. A) adaptation B) nonadaptive traits C) convergent traits D) developmental homology E) acclimation

Over long periods of 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? A) Natural selection accounts for these losses by the principle of use and disuse. B) Under particular circumstances that persisted for long periods, each of these structures presented greater costs than benefits. C) The ancestors of these organisms experienced harmful mutations that forced them to lose these structures. D) Natural selection cannot account for losses, but accounts only for new structures and functions.

A proficient engineer can easily design skeletal structures that are more functional than those currently found in the forelimbs of such diverse mammals as horses, whales, and bats. The actual forelimbs of these mammals do not seem to be optimally arranged because _____. A) natural selection is generally limited to modifying structures that were present in previous generations and in previous species B) though we may not consider the fit between the current skeletal arrangements and their functions excellent, we should not doubt that natural selection ultimately produces the best design C) natural selection has not had sufficient time to create the optimal design in each case, but will do so given enough time D) in many cases, phenotype is determined by genotype and the environment

The sickle-cell allele is pleiotropic (that is, it affects more than one phenotypic trait). Specifically, this allele affects oxygen delivery to tissues and affects one's susceptibility to malaria. Under conditions of low atmospheric oxygen availability, individuals heterozygous for this allele can experience life-threatening sickle-cell "crises." Such individuals remain less susceptible to malaria. Thus, pleiotropic genes/alleles reveal that _____. A) evolution is limited by historical constraints B) adaptations are often compromises C) chance events can affect the evolutionary history of populations D) new advantageous alleles do not arise on demand

Why was Darwin and Wallace's theory of evolution by natural selection revolutionary? A) It proved that individuals acclimated to their environment over time. B) It dismissed the idea that species are constant and emphasized the importance of variation and change in populations. C) It was the first time a biologist had proposed that species changed through time. D) It was the first theory to refute the ideas of special creation

Who proposed that organisms could be organized into a great chain of being? A) Lamarck B) Aristotle C) Linnaeus D) Darwin E) Wallace

Which of the following statements is an example of typological thinking? A) Women are shorter than men, have longer hair and like to shop. B) It is best to choose the seeds from the plants with the largest fruits to set aside for next year's plantings. C) The type of beak that is most advantageous varies depending on how much rain falls in a given year. D) The variety of dog shape and size is truly amazing

Which of the following scientists argued that variation among individuals allows evolution to occur? A) Linnaeus B) Lamarck C) Wallace D) Aristotle

Evolutionary theory predicts that species are related, not independent. Four of the following examples provide support for this prediction. Which one of these examples does not support the claim that species are related? A) Ground squirrel species found on the north and south sides of the Grand Canyon are similar behaviorally, despite being very different physically. B) Before synthetic insulin was available, diabetics used injections of purified pig insulin to manage their disease. C) All prokaryotes and eukaryotes use DNA to carry their genetic information. D) The endostyle of lancelets (invertebrate chordates) and the thyroid gland of vertebrates develop similarly, and both produce iodinated proteins. E) Plants that live in desert regions typically have thickened leaf surfaces to prevent water loss

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. A) Condition 1 only B) Condition 2 only C) Conditions 1 and 2 D) Conditions 2 and 3 E) Conditions 1, 2, and 3

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 _____. (choose one) A) almost all M. tuberculosis in the standard nutrient cell cultures carry the rpoB gene mutation, but very few of the M. tuberculosis in the cell cultures with rifampin carry the rpoB mutation B) very few M. tuberculosis in any of the cell cultures carry the rpoB gene mutation C) almost all of the M. tuberculosis in both types of cell cultures carry the rpoB mutation D) very few M. tuberculosis in the standard nutrient cell cultures carry the rpoB gene mutation, but almost all of the M. tuberculosis in the cell cultures with rifampin carry the rpoB mutation E) a mix of both M. tuberculosis strains thrive in the standard cell cultures, but no living bacteria can be found in the cell cultures that contain rifampin

Tourist companies start visiting Island X, where a population of medium ground finches (see question 20) 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? A) evolution of yet larger, deeper beaks over time, until all birds have relatively large, deep beaks B) increased variation in beak size and shape over time C) no change in beak size and shape over time D) evolution of smaller, pointier beaks over time, until all birds have relatively small, pointy beaks

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 greater relative fruit set than Claytonia with white flowers. Nevertheless, the percentage of different flower colors remains stable in the study population from year to year. Which of these statements might explain this observation? A) There are repeated mutations for white flowers in this species. B) The white flowers have evolved pollinator resistance. C) Flower color is not heritable but is instead environmentally determined. D) Reproductive success does not affect evolution in this species. E) Fitness is primarily determined by fruit set in this species

The distribution of pocket-mouse coat colors in several Arizona populations is associated with substrate color. Some populations live on light-colored granite substrate, and others live on dark volcanic rock. In Figure 24.2, 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-colored 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 colored. Which of the following statements best interprets the results shown in charts A and B? A) Frequency of the D allele is associated neither with the melanic phenotype nor with the presence of dark substrate color. B) Frequency of the D allele does not vary. C) Frequency of the D allele is closely associated with both the melanic phenotype and the presence of dark substrate color. D) Frequency of the D allele is not associated with the melanic phenotype, but is associated with the presence of dark substrate color. E) Frequency of the D allele is closely associated with the melanic phenotype, but is unrelated to the presence of dark substrate color

An individual with a novel adaptation has evolved that adaptation. A) true B) false

Parasitic species tend to have simple morphologies. Which of the following statements best explains this observation? A) Parasites have not yet had time to progress, because they are young evolutionarily. B) Parasites do not live long enough to inherit acquired characteristics. C) Parasites are lower organisms, and this is why they have simple morphologies. D) Simple morphologies have been naturally selected for in most parasites.

Vestigial traits and neutral changes in DNA sequences are good examples of _____. A) convergent traits B) nonadaptive traits C) adaptation D) acclimation E) developmental homology

Which of the following is a fitness trade-off? A) In some hornbill species, the male helps seal the female in a tree with her nest until the young are ready to fledge. B) Some lemmings run into the sea when overgrazing threatens the species. C) Moths are the best pollinators for datura flowers, but bees are the best pollinators for orchids. D) Algal genotypes that can grow rapidly in nitrogen-limited environments are easier for predators to digest.