1
Nonrandom associations between alleles at different loci are referred to by
which of the following terms? a.Heterozygosity
b.Ecotype
c.Cline
d.Norm of reaction
e.Linkage disequilibrium
E. Linkage disequilibrium
2
Refer to the figure below. The data of this graph, which plots heterozygosity
for a variety of human populations, support which of the following?
e.The “Out of Africa” hypothesis
3
Refer to the photographs below. The snow goose (Chen caerulescens) has
both a blue and white morph. Inheritance is Mendelian: BB and Bb
individuals are blue, while bb individuals are white. If 23 geese in a
population of 142 are white and 119 are blue, how many of the blue geese
would you expect to be carriers of the b allele (i.e., Bb heterozygotes)?
b.68
4
Population A has 11 segregating mitochondrial haplotypes. Populations B
and C have only two of the haplotypes that are present in population A.
Allele frequencies are similar in populations B and C. Which of the
following demographic scenarios is consistent with this mitochondrial data?
c.Populations B and C arose from population A, and high levels of gene flow
connect populations B and C.
5
Refer to the figure below. The graph shows the chromosomal variation in the
natural populations of Drosophila pseudoobscura studied by Dobzhansky.
Which of the following conclusions follows from the data in the graph?
b.Most deleterious recessive alleles exhibit partial lethality.
6
Artificial selection experiments almost always show a response to selection.
What is the most likely explanation for this observation?
a.Populations contain significant amounts of additive genetic variation.
7
Refer to the figure below. The graph shows the frequency distribution for a
particular trait (number of dermal ridges) in a sample of British men. Many
such quantitative traits have a normal distribution. What is a likely cause of
this?
c.Many traits are polygenic and the effects of alleles are additive
8
The additive genetic variance of fiddler crab claws is 0.50, while the
environmental variance is 0.30. What is the heritability of this trait?
c.0.625
9
Refer to the figure below. The graph represents the mortality rate of
offspring from marriages registered in 1903–1907 in Italian populations. The
data indicate that the offspring of related individuals have higher mortality
rates. What is a likely cause of this inbreeding depression?
c.Inbred individuals are more likely to be homozygous for deleterious
recessive alleles.
10
Which of the following populations is least likely to be affected by the
homogenizing effects of gene flow?
e.Bird populations that share wintering grounds but not breeding grounds
11
A population of prairie chickens has recently undergone a reduction in
population size, and inbred matings are now common. If this population is
observed in the next few generations, one would expect to see which of the
following patterns? (Assume that natural selection is absent.)
a.Heterozygosity decreasing over time, with greater changes occurring in the
first few generations
12
Heritability estimates of IQ increased after the establishment of a number of
social welfare programs (such as Head Start). Which of the following is the
most likely explanation for this effect?
d.The environmental variance decreased.
13
Which of the following observations would not violate the assumptions of
the Hardy-Weinberg principle?
b.Individuals migrate from nearby populations but die prior to breeding.
14
If two species of cichlid fish are observed in the same lake, they are said to
be _______. If two species of birds are observed as living only on separate
continents, they are said to be _______.
a.sympatric; allopatric
15
Refer to the figure below. The figure shows that high levels of DNA
sequence variation are observed at the Adh locus in Drosophila
melanogaster. Based on this observation, which of the following conclusions
would be false?
e.DNA sequence polymorphisms occur only within introns.
16
Which of the following sources of variation is most important to evolution?
a.Genetic changes
17
Which of the following would be the best way to test whether larger body
size in amphipods is an adaptation to risk of predation?
b.Correlate body size with predation risk across a number of closely related
species, taking into account phylogenetic relationships.
18
Alarm calls by ground squirrels alert other ground squirrels to danger, but
they draw attention to the caller and expose it to increased risk of predation.
Such altruistic behavior is best explained by the phenomenon of
d.kin selection.
19
Not all traits are adaptations. Which of the following may also explain the
evolution of a particular trait?
e.All of the above
20
A feature that reduces the fitness of an individual but benefits the population
or species
d.All of the above
21
Species selection occurs when there is a correlation between some trait and
the rates of two processes: _______ and _______.
c.speciation; extinction
22
Which of the following conditions would most likely lead to an increase in
the frequency of an altruistic behavior in a population?
e.The beneficiaries of the behavior are related to the individual performing
it.
23
Which of the following traits can be thought of as a preadaptation for the
corresponding function?
b.Kea’s beak → piercing skin
24
Meiotic drive, or segregation distortion, is an example of
d.genic selection.
25
Which of the following conditions cannot cause the evolution of an
adaptation?
c.Future extinction of a population
26
A feature that may have evolved not because it conferred an adaptive
advantage, but because it was correlated with another feature that did have
an adaptive advantage, is an example of
c.hitchhiking.
27
The fitness of a biological entity is
d.its average per capita rate of increase in numbers.
28
Which of the following statements about adaptations is false?
e.They are developed by individuals in response to the needs of the
individual.
29
Which of the following is defined as any consistent difference in fitness
among phenotypically different classes of biological entities as a
consequence of competition for mates?
c.Sexual selection
30
Wings used for swimming in alcids are an example of
b.an exaptation.
31
The biological species concept has been widely adopted, but it also has some
practical difficulties. Which of the following is not one of these difficulties?
a.The concept is poorly defined.
36
The difference between primary and secondary hybrid zones is that primary
hybrid zones _______, while secondary hybrid zones _______.
b.are formed in situ as natural selection alters allele frequencies in
continuously distributed populations; arise when two formerly allopatric
species come in contact again
37
Refer to the figure below depicting a gene tree for populations of the crested
auklet (Aethia cristatella) and the least auklet (A. pusilla). Sequences of the
crested auklet are labeled with a blue C, while sequences of the least auklet
are labeled with a red L. A vertical red line indicates the timing of
speciation. What phenomenon does this figure depict?
b.Incomplete lineage sorting
38
Coyne and Orr’s studies of reproductive isolation and genetic divergence
between pairs of Drosophila populations and species discovered that
c.among recently diverged populations, premating isolation tends to be
stronger than postmating isolation.
39
According to the biological species concept, speciation consists of the
evolution of biological barriers to gene flow. The most important distinction
is between _______ and _______ barriers.
e.prezygotic; postzygotic
40
Epistatic interactions that underlie postzygotic isolation are called _______
incompatibilities.
d.Dobzhansky-Muller
41
Two populations become reproductively isolated from each other. Initially
they shared many of the same gene lineages, but over time different lineages
are lost in each population and eventually these populations may speciate.
Which of the following describes how genetic lineages change over time in
this hypothetical scenario?
e.Polyphyly → paraphyly → monophyly
42
The notion that a species is a single lineage of populations or organisms that
maintains a separate identity from other lineages is called the _______
species concept.
e.evolutionary
43
Which of the following terms refers to a variance of a species that is
associated with a particular type of habitat?
d.Ecotype
44
Refer to the figure below. The genomes of two species of jimsonweed
(Datura stramonium and D. discolor) differ by multiple translocations, and
F1 hybrids of these two species have distinctive chromosomal pairings. An
implication of this rearrangement is that
b.aneuploidy in the offspring of F1 individuals is likely.
45
Which of the following ideas is central to the biological species concept?
d.Reproductive isolation
46
Which of the following is evidence for allopatric speciation among finch
species of the Galápagos Islands?
d.No pairs of sister species appear on the same island.
47
Which of the following observations does not provide evidence that sexual
selection can be an important cause of speciation?
e.In many species, recombination rates differ for males and females.
48
Most examples of polyploidy speciation involve
a.plants.
49
Which of the following statements about peripatric speciation is true?
d.It can explain the sudden appearance in the fossil record of new species.
50
Which of the following is a definition of allopatric speciation?
c.Evolution of genetic reproductive barriers between populations that are
geographically separated
51
Why does reinforcement involve a strengthening of prezygotic, rather than
postzygotic, isolation?
d.Strengthening postzygotic isolation would require that alleles that reduce
fitness increase in frequency.
52
Why is it difficult to measure speciation rates over evolutionary time scales?
c.High diversification rates can be due either to high rates of speciation or to
low rates of extinction.
53
You collect individuals from different allopatric populations of the leaf
beetle Neochlamisus bebbianae. Back in the laboratory, you conduct matechoice experiments to assess levels of reproductive isolation among beetles
from different populations. Assuming that ecological speciation occurred in
the wild, what patterns should you expect?
d.Populations that share similar habitats will be less reproductively isolated.
54
Most models of sympatric speciation postulate the existence of
c.disruptive selection based on resource use.
55
Which mode of speciation involves intermediate levels of gene flow?
c.Parapatric speciation
56
Hawthorn trees were the ancestral hosts of the apple maggot fly (Rhagoletis
pomonella). In the last 150 years, however, cultivated apples have become a
host for some populations of R. pomonella. Development times differ for
populations that prefer different host plants, and emergence time is an
important ecological trait. Allele frequencies vary by latitude and host plant.
Which of the following details weakens the argument that this is an example
of sympatric speciation?
d.The divergence in development time for the hawthorn-feeding populations
occurred in Mexico, not the northeastern United States.
57
The central problem of speciation is how two different populations can be
formed without-out intermediates. Solutions to this problem are called
modes of speciation. The major criteria used to distinguish modes of
speciation are
e.the geographic origin of barriers to gene flow, the genetic bases of these
barriers, and the evolutionary causes of barriers.
58
What enables Dobzhansky-Muller incompatibilities to become established?
a.Neither of two allopatric populations passes through a stage at which
inferior genotypes are observed
59
How do rates of morphological evolution differ for phyletic gradualism and
punctuated equilibrium models of evolution?
d.In the punctuated equilibrium model, faster rates occur with speciation.
60
Refer to the figure below showing the hybrid origin of diploid species of
sunflowers. The sunflower phylogeny indicates that
61
Populations that breed at different seasons or different times of day are
examples of:
b. prezygotic temporal isolation
62
Secondary hybrid zones arise when two formerly allopatric species come in
contact again.
a. True
63
Random genetic drift refers to changes in allele and genotype frequencies
from the previous generation in very large populations only.
a. False
64
Natural selection is a consistent difference in finess among phenotypically
different biological entities.
a. True
65
Which of the following ideas is central to the biological species concept?
c. Reproductive isolation
66
The heterogametic sex in humans and insects is:
a. Male
67
A monophyletic group of animals or plants with a Gondwanan distribution
would be expected to have a present day distribution that includes:
a. South America, Africa, Madagascar, and India
68
The wings of penguins are modified for underwater swimming, but are still
fully functional as wings that allow these birds to fly once they have dried
out on land.
b. False
69
A feature that may have evolved not because it conferred an adaptive
advantage, but because it was correlated with another feature that did have
an adaptive advantage, is an example of
b. hitchhiking.
70
If mating in a population is non-random then the genotype frequencies may
depart from the ratios p2:2pq:q2.
b. True
71
Variation in a phenotypic character can have several sources other than
encoded in DNA sequences. All of the following are examples of
environmental sources of variation EXCEPT:
d. DNA mutations
72
Wings used for swimming in flying seabirds such as auks are an example of:
a. an exaptation.
73
Prezygotic barriers include hybrid inviability and hybrid sterility.
a. False
74
An alteration of the genotype frequencies in one generation alters the
frequency of alleles in their gametes, and this changes the genotype
frequencies in the following generation.
True
75
Which of the following statements about adaptations is false?
d. They do not enhance fitness
76
A vivariant history of successive separation of faunas on ancient continents
is likely to yield a phylogeny that parallels the separation of the continents.
true
77
Which of the following conditions would most likely lead to an increase in
the frequency of an altruistic behavior in a population?
d. Behavior whose beneficiaries are related to the individual performing it.
78
Alligators found in the USA and in China are examples of organisms that
have a disjunct distribution.
true
79
Animals and plants found in Malaysia are part of which biogeographic
realm?
b. Oriental