Chapter 22

A group of small fish live in a lake with a uniformly light-brown sandy bottom. Most of the fish are light brown, but about 10 are mottled. This fish species is often prey for large birds that live on the shore. A construction company dumps a load of gravel in the bottom of the lake, giving it a mottled appearance. Which of these statements presents the most accurate prediction of what will happen to this fish population?

The proportion of mottled fish will increase over time.

Which of the following correctly describes what the video referred to as a "microbial cure"?

Antibiotics are used to kill all of the infectious bacteria in a person.

Which of the following statements best defines artificial selection?

Artificial selection is a process in which humans decide which plants and/or animals will and will not breed.

Over time, bacteria have become increasingly resistant to antibiotics. Which of the following best explains this in terms of natural selection?

Bacteria that happen to have natural resistance to antibiotics survived and reproduced.

Darwin and Wallace independently arrived at the same conclusion that species change over time. Which observations supported their conclusions?

Bird families clustered geographically: cockatoos in the Malay Archipelago and Australia, macaws and hummingbirds in the Americas. The bony shells of armadillos resembled fossilized shells from the extinct Glyptodon.Tortoises from different Galapagos islands have distinct shells. Birdwing butterflies were found throughout the Malay archipelago, but species differed slightly from island to island. Mockingbirds from different Galapagos islands had subtle, consistent differences. The fossilized remains of giant sloths were similar to the smaller, living sloths Darwin encountered.

Darwin and Wallace made independent observations in different parts of the world. Which statements are true?

Both collected huge numbers of specimens and realized that individuals vary within species. Both observed slightly different species on nearby islands and concluded that species could change over time. Both witnessed nature up close and realized it was a battlefield with massive casualties.

What happened in the soapberry bug population in central Florida when the bugs began to feed on seeds from the goldenrain tree fruits which are much closer to the fruit surface?

Bugs with shorter beaks had more access to food, allowing them to produce more offspring.

Which of the following possible studies would be the best design for testing if longer hair is an adaptive trait? Assume that hair length is a trait that is inherited.

Capture a group of males with long hair at random, and cut the hair very short in half of the males; then, compare the number of matings of males with their hair left unchanged vs. males with shortened hair.

Which of these conditions do NOT occur in populations evolving due to natural selection?

Individuals pass on most traits that they acquire during their lifetime.

Which of the following statements is most accurate in comparing scientific theories and scientific hypotheses?

Scientific theories are supported by, and make sense of, many observations, whereas scientific hypotheses are narrow, testable ideas.

The cow Bos primigenius (which is farmed for meat and milk) has a smaller brain and larger eyes than closely related species of wild ungulates. Which of the following statements best describes the process that led to differences between domesticated/farmed cows and their wild relatives?

Artificial selection resulted in changes in the lineage leading to domesticated cows because humans wanted animals with high milk output and high muscle content.

How does natural selection act on beak length in soapberry bug populations?

The action of natural selection on beak length in soapberry bug populations varies with the environment.

Which of the following are testable hypotheses that could explain the researchers' data? Select all that apply.

The population size of cliff swallows living near roads has decreased over time. Scavenger population sizes have increased, and more road-killed swallows get eaten before they can be found. Traits that help individuals avoid being hit by cars have evolved through natural selection in the cliff swallow population.

As Wallace traveled the Malay Archipelago, he noticed that western islands had placental mammals, like monkeys. Eastern islands had marsupial mammals, like kangaroos. How did Wallace explain this distribution?

The western islands were once connected to Asia and the eastern islands had been connected to Australia. The islands had never been connected to each other.

Starting from the wild mustard Brassica oleracea, plant breeders have created the strains known as Brussels sprouts, broccoli, kale, and cabbage. Which of the following statements is correct with regard to the wild mustard?

There is enough heritable variation in the wild mustard to permit these different varieties.

Why do dark-colored rock pocket mice on dark lava flows have white bellies?

There is no selection for dark bellies by visual predators

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?

Under particular circumstances that persisted for long periods, natural selection reduced each of these structures because they presented greater costs than benefits.

An adaptation is __________.

a trait that gives an organism a reproductive advantage in the current environment

Which of the following factors would most likely cause an increase in population size of a prey animal?

an improvement in eyesight

Given what we know about evolutionary biology, which of the following places would be the most likely to have the highest number of species that are unique to the area (that is, that had evolved in that place). Assume that the conditions have existed for at least a few million years.

an isolated group of ocean islands

Of the following anatomical structures, which is most homologous to the bones in the wings of a bird?

bones in the flippers of a whale

Darwin used the phrase "descent with modification" to explain which of the following ideas?

both the unity and diversity of life

In the video, what does the UK's Chief Medical Officer suggest for promoting the development of new antibiotics?

encouraging big pharmaceutical companies to start investing again in new drug research and development

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

flipper

Structures as different as human arms, bat wings, and dolphin flippers contain many of the same bones, which develop from similar embryonic tissues. These structural similarities are an example of ________.

homology

DNA sequences in many human genes are very similar to the sequences of corresponding genes in chimpanzees. The most likely explanation for this result is that

humans and chimpanzees share a relatively recent common ancestor.

Which of the following events is now most likely to occur to finch beaks on this island?

increased variation in beak size and shape over time

A heritable trait is one that

is determined at least in part by genes passed from parents to offspring.

Which of the following is an example of an adaptation in anole lizards?

long legs in the anole lizards that live primarily on the ground and tree trunks

Which of the following observations led to Darwin's major inferences?

members of a population vary in their heritable traits although organisms can produce huge numbers of offspring, many of these offspring do not survive

Evolution of shorter legs in anole lizards placed on small, hurricane-scrubbed islands is an example of which type of evolution?

microevolution

A biologist observes that a particular plant species is found in a forest but not in a nearby meadow. She hypothesizes that the plants could grow in the meadow but are not found there because their seeds have yet to land in the meadow. Which of the following would be the most appropriate way to scientifically evaluate this hypothesis?

scattering seeds in several areas of the meadow and observing whether they start to grow

Which of the following contributes the LEAST to the problem of antibiotic resistance?

taking the entire course of antibiotics as prescribed by the doctor

Which of the following is an example of the pattern of evolution?

the fossil record of the evolution of modern cetaceans

Which of the following statements best describes evolution?

Populations change genetically from one generation to the next.

What does Dr. Carroll mean when he says, "while mutation is random, natural selection is not"?

- Natural selection favors some mutations. -Natural selection acts on traits. -Mutations for advantageous traits are more likely to be passed on to the next generation.

Jonathan Losos and colleagues conducted experiments on small, hurricane-swept islands as "natural laboratories." Which of the following statements is true?

-There are many small islands with similar environments, meaning that researchers can repeat their experiments and observations in several locations. -Islands scrubbed by hurricanes allow researchers to introduce new lizard populations and observe their evolution. -Natural selection can lead to rapid changes. The average leg length of lizard populations decreased within a few generations.

Identify the four postulates of natural selection.

-Some trait differences are heritable. -Survival and reproductive success are variable among individuals in a population. -Individuals with certain traits are more likely to survive and reproduce. -Individuals in a population vary in the traits they possess.

In the lab, Nachman examined dark mice from two different populations living hundreds of miles apart. The mice looked nearly identical. Their dark color was caused by two different genes. What does this tell you?

-There are at least two genes involved in creating dark mouse fur. -Dark fur color evolved independently on each lava flow. -Under very similar conditions, natural selection can favor very similar adaptations. -Two completely different mutations in two separate genes can generate the same phenotype.

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

A cow that produces a large quantity of milk.

why did the bacteria grow up to the edge of the area with antibiotics, pause, then continue to grow across the area with antibiotics?

A few bacteria experienced random mutations in their DNA, which allowed some of them to grow even though antibiotics were present.

What does it mean that organisms have a nearly universal genetic code?

A specific DNA sequence encodes the same information in one species as it would in nearly any other.

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

Adaptation

The theory of evolution through natural selection is considered a scientific theory because __________.

All of the listed answers are correct.

Which of the following observations most strongly supports the common origin of all life on Earth?

All organisms use essentially the same genetic code.

Which of the following statements best describes Darwin's theory of evolution by natural selection?

Darwin's theory emphasized that populations vary and change over time.

What is the meaning of Darwin's expression "descent with modification"?

Descent with modification refers to evolutionary change over time.

DNA evidence suggests that anole lizard species from the four largest Caribbean islands are related as shown in the figure. Which statement is true?

Different body types evolved repeatedly and independently on each island.

What is the most important characteristic of anole lizard species that keeps members of one species from mating with members of another species?

Different species living in the same habitat have different dewlaps.

Which of the following statements about evolutionary trees is accurate?

Evolutionary trees are considered evolutionary hypotheses.

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

Heritability

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.

When dark-colored fur gives mice a 1% competitive advantage and 1% of the population begins with dark fur, in about 1000 years, 95% of the population will have dark fur. Which of the following statements is true?

If dark-colored rock pocket mice had a competitive advantage of 0.1%, it would take longer for 95% of the population to have dark fur.

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 due to differences in certain traits.

It has been observed that organisms on many islands are different from, but closely related to, similar forms found on the nearest continent. Which of the following possible conclusions is best derived from this observation?

Island forms are descended from mainland forms.

Which of the following statements is accurate about an organ described as vestigial?

It must be homologous to some feature in an ancestor.

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

Large hen, large rooster

Which of the following statements best describes Linnaeus' method of classifying organisms?

Linnaeus grouped organisms into increasingly more inclusive categories.

Which of the following statements is likely most accurate about Thrinaxodon?

Mammals evolved from a relative of Thrinaxodon.

What did Wallace conclude from observing that the bones in manatee flippers look similar to the bones in a human arm and hand?

Manatees' arm and finger bones are evidence that manatees share a common ancestor with land mammals.

Identify the pair of homologous structures.

Maple leaf and oak leaf

When Charles Darwin set sail on the HMS Beagle, what did he and most of his contemporary scientists think about the origin of species?

Most scientists, including Darwin, thought each species was specially created by God in its present form and did not change over time.

Which of the following statements about natural selection is true?

Natural selection favors individuals that reproduce more than others.

The upper forelimbs of humans and bats have fairly similar skeletal structures, whereas the corresponding bones in whales have very different shapes and proportions. However, genetic data suggest that all three kinds of organisms diverged from a common ancestor at about the same time. Which of the following is the most likely explanation for these data?

Natural selection in an aquatic environment resulted in significant changes to whale forelimb anatomy.

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.

Nearly 100% of monkey flowers growing in copper-contaminated soil are copper tolerant. The population that existed before mining must have included both copper-tolerant and copper-intolerant plants. 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.

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.

Which of the following statements is most consistent with data obtained from the fossil record?

Older strata carry fossils that differ greatly from living organisms.

A particular antibiotic kills 99% of a bacterial population. What will be the result of the continued application of this antibiotic?

Over time, the antibiotic will become less effective at killing the bacteria.

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

Some drug-resistant bacteria were present at the start of treatment, and natural selection increased their frequency.

Which of the following observations helped Darwin shape his concept of descent with modification?

South American temperate plants are more similar to South American tropical plants than to European temperate ones

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

Species X and Y share a greater number of homologies with each other than either does with species Z.

After his journey on the HMS Beagle, Darwin made this now-famous sketch in his notebook. Which ideas does it represent?

Species descend from other species just as naturally as children come from parents. All species are linked to one another by common ancestry. All species are connected to one another in a "family tree."

Which of the following is an observation or inference on which natural selection is based?

Species produce more offspring than the environment can support.

In 1959, doctors began using the powerful antibiotic methicillin to treat infections of Staphylococcus aureus, but within two years, methicillin-resistant strains of S. aureus (MRSA) appeared. How did the resistant strains of S. aureus emerge?

Staphylococcus aureus bacteria that were able to synthesize cell walls using a protein that was not affected by methicillin survived the methicillin treatments and reproduced at higher rates than did other individuals. Over time, these resistant individuals became increasingly common.

Which observations led Darwin to establish a relationship between extinct and living animals?

The bony shells of armadillos resembled the shells of ancient Glyptodon fossils.The fossilized remains of giant sloths were found in places where smaller sloths now live.

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.

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.

Members of two different species possess a similar-looking structure that they use in a similar way to perform about the same function. Which of the following observations would suggest that the relationship more likely represents homology than convergent evolution?

The embryological development of the two structures are similar.

Given no other information, if the researcher removes all slugs from the study population, what do you predict will most likely happen to the percentage of flower colors in the population over time?

The percentage of pink flowers will increase over time.

Varieties of Staphylococcus aureus that are resistant to the drug methicillin __________

The second and fourth answers are correct.

DDT was once considered a "silver bullet" that would permanently eradicate insect pests. Instead, DDT is now largely ineffective against many insects. Which of the following possible actions would have had the best chance of preventing this evolution of DDT resistance?

The use of DDT should have been interspersed with the use of other pesticides that have a different mode of action.

What is the concern about using antibacterial and antimicrobial soaps?

The use of any chemical that kills bacteria can eventually lead to resistance to that chemical in the population of bacteria.

If the bacterium Staphylococcus aureus experiences a cost for maintaining one or more antibiotic-resistance genes, what would be most likely to happen in environments that lack antibiotics?

These bacteria would be outcompeted and replaced by bacteria that have lost the antibiotic resistance genes.

Why did dark-colored rock pocket mice first appear in a population of light-colored rock pocket mice?

They have a genetic mutation that affects their fur color.

Which of the following statements best explains the return of pigweed to the farmer's fields?

Triazine-resistant weeds were more likely to survive and reproduce than were non-resistant individuals.

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

Mutations are always __________.

a change in an individual's DNA

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

From his observations of organisms in the Galapagos Islands, Darwin reasoned that __________.

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

Charles Darwin __________.

proposed natural selection as the mechanism of evolution

In this diagram, each fork represents which of the following ideas?

the most recent common ancestor of the subsequent species

Which one of the following researchers developed a theory of evolution that was very similar to Charles Darwin's?

wallace