Evolution and Natural Selection - W.H. Freeman

12. Adaptation:
a) refers both to the process by which organisms become
better matched to their environment and to the features of
an organism that make it more fit than other individuals.
b) cannot occur in environments influenced by humans.
c) is possible only when there is no mutation.
d) is responsible for the fact that porcupines are at unusually
high risk of predation.
e) occurs for physical traits but not behaviors.
13. Adaptations shaped by natural selection:
a) are magnified and enhanced through genetic drift.
b) are unlikely to be present in humans living in industrial
societies.
c) may be out of date, having been shaped in the past under
conditions that differed from those in the present.
d) represent perfect solutions to the problems posed by nature.
e) are continuously modified so that they are always fitted to
the environment in which an organism lives.
14. Artificial selection was used on corn to produce a single strain
of corn with increased growth rates and greater resistance to
a fungus. Although farmers have continued to select for these
traits, the productivity of this strain is no longer increasing.
This suggests that:
a) the population size has been decreasing.
b) all or most of the natural variation for these traits has been
eliminated.
c) gene migration is a major evolutionary agent in corn.
d) long-term disruptive selection may lead to speciation.
e) artificial selection is not as strong as natural selection.
15. In a population in which a trait is exposed to stabilizing
selection over time:
a) neither the average nor the variation for the trait changes.
b) both the average value and variation for the trait increase.
c) the average value increases or decreases and the variation
for the trait decreases.
d) the average value for the trait stays approximately the same
and the variation for the trait decreases.
e) the average value for the trait stays approximately the same
and the variation for the trait increases.
16. Maze-running behavior in rats:
a) is too complex a trait to be influenced by natural selection.
b) is a heritable trait.
c) is not influenced by natural selection because it does not
occur in rats’ natural environment.
d) shows no variation.
e) is influenced primarily by mutation in the laboratory.
17. A fossil is defined most broadly as:
a) the preserved pieces of hard parts (e.g., shell or bone) of
extinct animals.
b) any preserved remnant or trace of an organism from the
past.
c) the preserved bones of vertebrates.
d) a piece of an organism that has turned into rock.
e) the process of preservation of intact animal bodies.
18. Which of the following are correct about marsupial mammals?
a) fill many niches in Australia that are occupied by placental
mammals in other parts of the world.
b) are less fit than placental mammals.
c) have gone extinct as a result of the greater fitness of
placental mammals.
d) are more closely related to each other than they are to
placental mammals.
e) Both a) and d) are correct.
19. Convergent evolution can occur only when two species:
a) have a recent common ancestor.
b) live in the same geographic area.
c) are separated by a barrier such as a new river.
d) evolve under similar selective forces.
e) are both unpalatable to predators.
20. What can be concluded about comparing differences in
molecular biology between different species?
a) Extremely different species are fundamentally unrelated in
any way.
b) Only DNA sequences can be used to compare relatedness
between species.
c) Birds are more closely related to humans than dogs are.
d) Genetic similarities and differences demonstrate species
relatedness.
e) The longer two species have been evolving on their own,
the fewer the genetic differences between them.
21. Evolution:
a) occurs too slowly to be observed in nature.
b) can occur in the wild but not in the laboratory.
c) is responsible for the increased occurrence of antibioticresistant
bacteria.
d) does not occur in human-occupied habitats.
e) None of these statements is correct.
Sh o r t -An s w e r Qu e s t i o n s
1. Distinguish between evolution and natural selection. (Restrict
your answer to 30 words or fewer.)
2. What is genetic drift? Why is it a more potent agent of
evolution in small populations rather than large populations?
3. In The Origin of Species, Charles Darwin wrote: “We may look
with some confidence to a secure future of great length. And
as natural selection works solely by and for the good of each
being, all corporeal and mental endowments will tend to
progress towards perfection.” Describe three reasons why he
is wrong.
4. How does the increasing frequency of antibiotic-resistant
strains of bacteria represent an example of the occurrence
evolution?
See Appendix for answers. For additional study questions,
go to www.prep-u.com.
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