Classroom Test of Evolutionary Reasoning (CTER)
DO NOT WRITE ON THIS EXAM – PLEASE USE THE ANSWER SHEET
1. A population of insects is uniformly sprayed with a powerful insecticide. Ninetyfivepercent of the insects are killed. If the five percent of the insects that survive all
reproduce and the next generation of insects is uniformly sprayed with the same
insecticide again, we would predict that:
A. almost all of the insects will be killed by the second spraying.
B. about the same number of the insects will be killed by the second spraying.
C. a much lower percentage of the insects will be killed by the second spraying
D. almost all of the insects will survive the second spraying.
2. The most likely explanation for the survival rates of the insects after the second
spraying is that:
A. insects that survived the first spraying were genetically resistant to the insecticide.
B. individual insects that survived the first spraying became more resistant over time.
C. the insecticide is powerful enough to kill most of the insects.
3. In the mountains of California, the yarrow plant grows at elevations that range from
4,000 feet (below timberline) to 12,000 feet (above timberline). The plants that grow near
or above timberline are much shorter on average than those growing near the 4,000 foot
level. This difference could be due to either natural selection or it could be due to the
effects of environmental conditions on the growth of individual plants.
Suppose that seeds collected from yarrow plants growing at both elevations (i.e., 4,000
feet and 12,000 feet) are planted in garden plots at 4,000 feet and grown under identical
conditions. If the observed differences in height were due to natural selection rather than
to environmental conditions, which statement best describes the probable results of
growing these two groups of seeds?
12. Classroom Test of Evolutionary Reasoning Part 1
A. Both types of seeds will grow into plants of about the same average height as the
plants growing at 4,000 feet.
B. Both types of seeds will grow into plants of an average height that is in-between
those growing at 4,000 feet and those growing at 12,000 feet.
C. Seeds collected from plants growing at 4,000 feet will grow into much taller
plants than those collected from plants growing at 12,000 feet.
D. Seeds collected from plants growing at 12,000 feet will grow taller than the
parental plants (i.e., plants still at the 12,000 foot level).
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4. We will see this height pattern in the plants grown from the two groups of seeds
because:
A. the environmental conditions will promote the growth of taller plants in this
experiment.
B. the environmental conditions will act to cause all of the seeds to grow to the same
height.
C. the frequencies of the genetic alleles (different forms of the genes) that affect
plant height will be very similar in the two groups of seeds.
D. the frequencies of the genetic alleles (different forms of the genes) that affect
plant height will be very different in the two groups of seeds.
5. In many species of cave animals, all of the members are blind and albino (i.e., they
have no pigment). This includes several species of cave salamanders. Based upon this
observation, a scientist conducted the following experiment:
A large number of salamanders with both normal pigment and normal eyesight were
isolated from each other by placing them in individual containers. The containers were
kept in total darkness for several years. At the end of this time period, all of the
salamanders were placed back together in a very large container and allowed to mate
randomly with each other. The offspring of these matings were then examined. Which of
the following predictions would you make about the outcome of the experiment?
A. Many of the offspring should have less pigment and poorer eyesight than the
parents.
B. About one-fourth of the offspring should have less pigment and poorer eyesight
than the parents.
C. The offspring should have about the same amount of pigment and eyesight as
good as the parents.
6. Why will the offspring of the salamanders have the amount of pigmentation and
quality of eyesight you predicted above?
A. Because the salamanders kept in the dark will not benefit from having pigment or
eyesight.
B. Because the amount of pigment and quality of eyesight are recessive traits.
C. Because the genes of the salamanders will not be altered by exposure to the
darkness.
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7. A paleontologist has collected fossils from three different locations for a number of
years. At location "A", she collected fossils representing 512 different species; of these,
256 were still living today. At location "B", she collected 215 fossil species; of
these, 43 were still living. At location "C", she collected 160 fossil species; of these, 128
were still living.
Assuming that the rates of extinction and fossilization were the same at each site, it can
be inferred from the above data that the oldest of the three locations is:
A. location "A".
B. location "B".
C. location "C".
8. We can infer that this is the oldest location because:
A. only 1 in 5 of the fossil species at this location is still alive today.
B. the smallest total number of fossil species is found at this location.
C. the largest total number of extinct species is found at this location.
9. Suppose that 512 dark colored moths and 472 light colored moths are captured,
marked, and released at the same location at which they were caught. After several days,
as many of each type of moth as possible are recaptured. If the environment did not
change over this period of time, which of the following best describes what we can
predict about the results of this experiment?
A. It is not possible to accurately predict the results of this experiment.
B. A higher percentage of dark colored moths will be more likely to be recaptured.
C. About the same number of each type of moth will be more likely to be recaptured.
10. Which of the following best describes your reasoning for selecting your previous
answer?
A. Equal numbers of light and dark moths were not released at the start of the
experiment.
B. No information about the environment where the moths were released is given.
C. Survival of these two types of moths should be random.
D. Approximately equal percentages of each type of moth were released at the start
of the experiment.
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11. Which of the following types of mutations should accumulate most rapidly over time
in the protein-coding genes of a population?
A. Silent mutations
B. Frameshift mutations
C. Missense mutations
D. Nonsense mutations
12. Why should the above type of mutation accumulate most rapidly?
A. Because this type of mutation should not affect protein function.
B. Because this type of mutation could alter protein function.
C. Because this type of mutation will usually be favored by natural selection.
13. Lungfishes, freshwater fishes with the ability to breathe air, are considered to be most
closely related to:
A. Sharks.
B. Trout.
C. Humans.
14. Lungfishes are considered to be most closely related to the above organism because:
A. they both have lungs.
B. they are structurally most similar to each other.
C. they have been separated from a common ancestor for the least amount of time.
15. Speciation of two sexually reproducing populations requires that:
A. the two populations become geographically isolated from each other by a physical
barrier (i.e., a river, mountain range, etc.).
B. the two populations look different from each other.
C. the two populations become reproductively isolated from each other.
D. the two populations become geographically isolated from each other by a physical
barrier (i.e., a river, mountain range, etc.), but come back into contact with each
other at a later date.
16. The above requirement is necessary for speciation because:
A. separate species cannot form hybrids.
B. populations must live in different habitats for speciation to occur.
C. separate species cannot continue to exchange genes to a significant extent.
D. separate species must look different so that they can tell each other apart.
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17. Which of the following statements best characterizes the evolutionary relationship of
humans to other, related species?
A. Humans evolved from chimpanzees.
B. Humans and chimpanzees share a recent, ape-like ancestor.
C. Humans are more highly-evolved than chimpanzees and other apes.
18. The best reason for selecting the answer above is because:
A. humans share 98.6% of their DNA sequences with chimpanzees.
B. humans have larger brains than chimpanzees and other apes.
C. humans walk on two legs while chimpanzees and other apes walk on four legs.
19. A large number of mice have their tails removed. These tailless mice are then allowed
to breed amongst themselves. This procedure is repeated for many generations. When the
offspring of the last generation of mice are examined, you would predict that:
A. none of the mice will be tailless.
B. about 75% of the mice will be tailless.
C. some mice will be tailless, but it is impossible to predict the exact percentage.
D. almost all of the mice will be tailless.
20. We will see these results in the last generation of mice because:
A. removing the tail will not remove the genes that cause tail development.
B. removing the tail will increase the proportion of tailless mice in each succeeding
generation.
C. removing the tail will have a progressive effect on each succeeding generation,
but we cannot predict the extent of that effect.
21. An example of a vestigial structure is:
A. the single toe bone of a horse.
B. an extra finger on the hand of a human being.
C. the pelvic bone of a snake.
D. the yolk sac of a chicken.
22. The best definition of a transitional fossil is:
A. a fossil that is a descendant of one group and an ancestor of a second, distinct
group.
B. a fossil whose features are in-between the features of its ancestors and its
descendants.
C. a fossil whose parents were members of one species and whose offspring are
members of another species.
D. a fossil whose combination of features connect it to two separate groups.
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23. Two physical (i.e., anatomical) characteristics in organisms are considered
homologous if:
A. they have the same structure.
B. they have the same or similar functions.
C. they are descended from a single structure in their most recent common ancestor.
D. they look alike, but are not found in their most recent common ancestor.
24. Which of the following factors would be most likely to cause a change in gene
frequency in a population?
A. Geographic isolation (by a physical barrier, i.e., a river, mountain range, etc.)
separating the population
B. Natural selection within the population
C. The passage of time
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Given the following Phylogenetic Tree of Life, answer questions 25 and 26 below.
25. Which of the following inferences could be made about the Archaea domain (marked
with an asterisk) in the phylogenetic tree of life shown above?
A. Thermoproteus evolved from Pyrodicticum.
B. Methanococcus is more closely related to Halophiles than to T. celer.
C. Halophiles are more evolved than Methanosarcina.
D. Methanobacterium is more closely related to Methanosarcina than to any other
group.
26. Which of the following best describes the reasoning behind the inference you just
made for the Archaea domain?
A. Methanococcus and Halophiles share a more recent common ancestor than
Methanococcus and T. celer.
B. The branch leading to Thermoproteus comes off of the branch for Pyrodicticum.
C. Methanobacterium and Methanosarcina share a more recent common ancestor
than Methanobacterium does with any other group.
D. Halophiles are placed on a branch further up the tree than the branch leading to
Methanosarcina.
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Given the following Phylogenetic Tree of Life, answer questions 27 and 28 below.
27. According to the phylogenetic tree of life above, which organism(s) is (are) most
closely related to plants (marked with an asterisk).
A. Ciliates
B. Fungi
C. Both fungi and animals
D. Both fungi and ciliates
28. Plants are most closely related to this (these) organism(s) because:
A. plants as a group lie between ciliates and fungi.
B. plants share a common ancestor with both animals and fungi.
C. plants as a group are placed closest to ciliates.
D. plants share a common ancestor with fungi and as a group, are placed closer to
fungi than to animals.
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Given the following phylogenetic trees of life, answer question 29 below.
29. Which of the following conclusions could be made about the phylogenetic trees
shown above?
A. In Tree A, the frog is more closely related to the fish than to the human.
B. In Tree B, the lizard is more closely related to the fish than to the frog.
C. Tree A shows the frog as being more closely related to the lizard than Tree B.
D. Tree B shows the frog as being more closely related to the mouse than Tree A.
E. Both Tree A and Tree B depict the same evolutionary relationships.
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