Ch 22 HW

Part B What was the researchers' main hypothesis?

Predation results in selection for more drab color patterns in guppies.

Part F In the United States today, about half of the corn crop is genetically engineered with a protein that is toxic to corn borers, an insect pest of corn. Which of the following conditions would be necessary for evolution of resistance to the toxic protein to occur in the corn borer?

The corn borer must have or generate (by mutation) heritable variation in resistance to the toxic protein. The resistant corn borers must survive better or reproduce more than nonresistant corn borers.

Part E Which of the following statements describes the evolution by natural selection of Mycobacterium tuberculosis bacteria in their new environment?

The drug-resistance trait is an adaptation to the environment in which human hosts are medicated with the antibiotic rifampin.

Part A Which of the following is(are) homologous to the bones in this image?

The picture of the dark brown bones (cat foot)

Part C - Natural selection in monkey flowers Some monkey flowers (Mimulus guttatus) living near the sites of copper mines can grow in soil containing high concentrations of copper, which is toxic to most plants. Copper tolerance is a heritable trait. The map below shows the area near an old copper mine, which contaminated the nearby soil with copper. A stream flows past the mine toward the lake at the bottom right of the map. Use the map to determine which of the statements below are true. Select the three statements that are true.

The population that existed before mining must have included both copper-tolerant and copper-intolerant plants. Nearly 100% of monkey flowers growing in copper-contaminated soil are copper tolerant. If you were to test monkey flowers growing on the shore of the lake, you would expect nearly 100% of them to be copper tolerant.

Part A From his observations of organisms in the Galapagos islands, Darwin reasoned that _____.

organisms had adapted to new environments, giving rise to new species

Part J What data should you collect in order to test your prediction?

predation rate on transplanted versus original source guppies, and color patterns of the population over time

Part D What was the control group in this study?

the source population in the pike-cichlid pools

Part E What was the experimental group in this study?

the transplanted population in the killifish pools

Part G True or false? It would be difficult to assess whether the drug-susceptible or drug-resistant phenotype in a population of Mycobacterium tuberculosis was more fit in an environment without antibiotics.

true

Part D Which of the following organisms could be produced by artificial selection?

A cow that produces a large quantity of milk.

Part B How many finch species did Darwin send to the British Museum?

13

Part F A farmer wishes to develop a strain of high-yield corn that is also resistant to drought. He has the following individuals from the current year's crop: Individual A—Yield: 179 bushels/acre; drought resistance: high Individual B—Yield: 220 bushels/acre; drought resistance: low Individual C—Yield: 185 bushels/acre; drought resistance: medium Individual D—Yield: 140 bushels/acre; drought resistance: high Individual E—Yield: 200 bushels/acre; drought resistance: medium Which of the following crosses would produce the highest corn yield with the highest resistance to drought?

A and E

Part B Which term describes a trait that increases an individual's ability to survive in a particular environment?

Adaptation

Part A - Identifying the elements of hypothesis-based science This experiment is an example of hypothesis-based science. What question did the researchers ask?

Can predation result in selection for color patterns in guppies?

Part A - Scientific evidence supporting evolution Scientific evidence documents the pattern of evolution. The evidence exists in a variety of categories, including direct observation of evolutionary change, the fossil record, homology, and biogeography. Sort the following examples into the correct categories. Drag each phrase to the appropriate bin.

Direct observation of evolutionary change = Development of drug resistant bacteria Fossil Records = Discovery of shells of extinct species Discovery of transitional forms of horses Homology = Same genetic code in fireflies and tobacco plants Similarities in mammalian forelimbs Vestigial pelvis in right whales Biogeography = Similarity of endemic island species to nearby mainland species the high concentration of Marsupial species in Australia

Part B Which of the following statements is an accurate combination of postulates 1 and 2 of natural selection?

Heritable variation exists for traits among individuals in a population.

Part A The Galápagos Islands are cooled by the _____.

Humboldt Current

Part C Which of the following statements is an accurate combination of postulates 3 and 4 of natural selection?

Individuals experience differential success in their ability to survive or reproduce.

Part E Which pair of chickens should a farmer breed to produce larger chickens?

Large hen, large rooster

Part A Which of the following statements about natural selection is true?

Natural selection favors individuals that reproduce more than others.

Part D Does the ability of a Mycobacterium tuberculosis cell to infect a new host depend on its drug-resistant phenotype?

No, drug-susceptible cells and drug-resistant cells are equally likely to infect a new host.

Part G - Interpreting the data What conclusion would you draw from the data presented?

Predation results in selection for more drab coloration in pike-cichlid pools.

Part I - Making and testing a prediction Suppose that after 22 months, guppies from the transplanted population were returned to the source pool. What would most likely happen to those guppies?

They would experience a higher rate of predation than the native population, and over time they would evolve and resemble the original source population.

Part F How did the types of data the researchers collected enable them to test their prediction?

Tracking the number and area of colored spots provided a quantitative way to compare the brightness of different populations.

Part A Which of these lists contains the four postulates of natural selection?

Variation in population, heritable variation, selection, differential survival or reproduction

Part C Researchers further hypothesized that if predation pressure is reduced, drab coloration would become less beneficial (since females prefer brightly colored mates). Based on this hypothesis, what prediction did the researchers test in this experiment?

When guppies with drab colors are transferred to a pool with only killifish, the transplanted population will evolve brighter colors than the original source population.

Part B - Phylogenetic trees and geographic relationships The island fox, Urocyon littoralis, is endemic to the Channel Islands, which are located off the coast of southern California. Six of the eight Channel Islands support fox populations, and each of these islands is home to a distinct subspecies, as shown in the table below. Island Subspecies Northern Channel Islands Santa Cruz U. l. santacruzae Santa Rosa U. l. santarosae San Miguel U. l. littoralis Southern Channel Islands San Nicolas U. l. dickeyi San Clemente U. l. clementae Santa Catalina U. l. catalinae The island fox shares a common ancestor with the gray fox, Urocyon cinereoargenteus, which is found on the mainland. Both species have similar coloration and a diploid chromosome number of 66. One structural difference between the two species is the reduced size of the island fox, a feature known as dwarfism. The various island subspecies also differ from each other in size, number of tail vertebrae, and other characteristics. The phylogenetic tree below shows the evolutionary relationships between the island fox subspecies and the gray fox. Drag the labels to their appropriate locations on the tree. First, drag the blue labels onto the blue targets to identify the common ancestors at the branch points. Next, drag one white label onto the white target to identify the homologous characteristic. Then, drag one pink label onto the pink target to identify the relationship between the two species.

a. ancestor of gray foxes and island foxes b. ancestor of Santa Rosa and San miguel foxes c. dwarfism d. ancestor of northern Channel Island foxes e. most closely related f. ancestor of southern channel foxes g. ancestor of island foxes h. ancestor of Santa Catalina and San Clemnte foxes

Part A A challenge to traditional (pre-1860) ideas about species came from embryology, when it was discovered that _____.

embryos of dissimilar organisms, such as sharks and humans, resemble each other

Part B The wing of a bat is homologous to the _____ of a whale.

flipper

Part C Which term describes the ability of a trait to be passed on to offspring?

heritability

Part H Which of the following would help strengthen the researchers' conclusion?

if no other characteristics differed significantly between the source and transplanted populations