Which of the following has been shown to cause speciation most
rapidly?
A. differential resource exploitation
B.
autopolyploidy
C. sexual selection
D. hybridization
E.
punctuated equilibrium
B
A certain species of salamander was split into two populations by a
wide, dry valley, and the populations began to diverge from each
other. After a period of time, some members of the two populations
began to interbreed in a hybrid zone at the southern end of the
valley. Only weak reproductive barriers existed by this time, so the
two populations could freely interbreed and re-establish gene flow.
This outcome in a hybrid zone is known as _____.
A.
speciation
B. punctuated equilibrium
C. fusion
D.
stability
E reinforcement
C
According to the concept of punctuated equilibrium, the
"sudden" appearance of a new species in the fossil record
means that
A.the species is now extinct.
B. speciation
occurred instantaneously.
C. the species will consequently have a
relatively short existence, compared with other species.
D.
speciation occurred in one generation.
E. speciation occurred
rapidly in geologic time.
E
The question refers to the following description.
On the Bahamian island of Andros, mosquitofish populations live
in various, now-isolated, freshwater ponds that were once united.
Currently, some predator-rich ponds have mosquitofish that can swim in
short, fast bursts; other predator-poor ponds have mosquitofish that
can swim continuously for a long time. When placed together in the
same body of water, the two kinds of female mosquitofish exhibit
exclusive breeding preferences.
What is the best way to promote fusion between two related
populations of mosquitofish, one of which lives in a predator-rich
pond, and the other of which lives in a predator-poor pond?
A.
Perform a reciprocal transfer of females between predator-rich and
predator-poor ponds.
B. Transfer only female mosquitofish from a
predator-rich pond to a predator-poor pond.
C. Remove predators
from a predator-rich pond and transfer them to a predator-poor
pond.
D. Build a canal linking the two ponds that permits free
movement of mosquitofish, but not of predators.
D
Which of the following statements about speciation is
correct?
A. Natural selection chooses the reproductive barriers
for populations.
B. When reunited, two allopatric populations
will interbreed freely if speciation has occurred.
C. It always
takes millions of years for speciation to occur.
D. The goal of
natural selection is speciation.
E. Speciation is a basis for
understanding macroevolution.
E
Which of the following is the first step in allopatric
speciation?
A. hybridization
B. polyploidy
C. formation
of a reproductive barrier
D. genetic drift
E. geographic isolation
E
In a hypothetical situation, a certain species of flea feeds only on
pronghorn antelopes. In rangelands of the western United States,
pronghorns and cattle often associate with one another. If some of
these fleas develop a strong preference for cattle blood and mate only
with other fleas that prefer cattle blood, then over time which of
these should occur, if the host mammal can be considered as the fleas'
habitat?
1. reproductive isolation
2. sympatric
speciation
3. habitat isolation
4. prezygotic barriers
A. 1 only
B. 2 and 3
C. 1, 2, and 3
D. 2, 3, and
4
E. 1 through 4
E
The question refers to the following description.
On the Bahamian island of Andros, mosquitofish populations live
in various, now-isolated, freshwater ponds that were once united.
Currently, some predator-rich ponds have mosquitofish that can swim in
short, fast bursts; other predator-poor ponds have mosquitofish that
can swim continuously for a long time. When placed together in the
same body of water, the two kinds of female mosquitofish exhibit
exclusive breeding preferences.
Which type of reproductive isolation operates to keep the
mosquitofish isolated, even when fish from different ponds are
reunited in the same body of water?
A. habitat isolation
B.
behavioral isolation
C. gametic isolation
D. temporal
isolation
E. mechanical isolation
B
Rocky Mountain juniper (Juniperus scopulorum) and one-seeded juniper
(J. monosperma) have overlapping ranges. If pollen grains (which
contain sperm cells) from one species are unable to germinate and make
pollen tubes on female ovules (which contain egg cells) of the other
species, then which of these terms are applicable?
1. sympatric
species
2. prezygotic isolation
3. postzygotic
isolation
4. allopatric species
5. habitat isolation
6.
reduced hybrid fertility
A. 1 and 2
B. 2 and 4
C. 1, 3, and 6
D. 2, 4, and
5
E. 1, 2, 5, and 6
A
Sympatric speciation is _____.
A. the process by which most
animal species have evolved
B. the emergence of many species from
a single ancestor
C. initiated by the appearance of a geographic
barrier
D. especially important in the evolution of island
species
E. the appearance of a new species in the same area as
the parent population
E
Hybrid zones provide an opportunity to investigate _____.
A.
polyploidy
B. allopatric speciation
C. the evolution of
reproductive isolation
D. mutations
E. punctuated equilibrium
C
Plant species A has a diploid number of 12. Plant species B has a
diploid number of 16. A new species, C, arises as an allopolyploid
from A and B. The diploid number for species C would probably
be
A. 28.
B. 16.
C. 12.
D. 56.
E. 14.
A
Bird guides once listed the myrtle warbler and Audubon's warbler as
distinct species. Recently, these birds have been classified as
eastern and western forms of a single species, the yellow-rumped
warbler. Which of the following pieces of evidence, if true, would be
cause for this reclassification?
A. The two forms have many genes
in common.
B. The two forms live in similar habitats.
C. The
two forms interbreed often in nature, and their offspring have good
survival and reproduction.
D. The two forms have similar food
requirements.
E. The two forms are very similar in coloration.
C
In the ocean, on either side of the Isthmus of Panama, are 30 species
of snapping shrimp; some are shallow-water species, others are adapted
to deep water. There are 15 species on the Pacific side and 15
different species on the Atlantic side. The Isthmus of Panama started
rising about 10 million years ago.
In the following figure, the isthmus separates the Pacific Ocean
on the left (side A) from the Atlantic Ocean on the right (side B).
The seawater on either side of the isthmus is separated into five
depth habitats (15), with 1 being the shallowest.
The Panama
Canal was completed in 1914, and its depth is about 50 feet. After
1914, snapping shrimp species from which habitats should be most
likely to form hybrids as the result of the canal?
A. A5 and B5
B. A3 and B3
C/ A1 and B1
D. either
A1 and A2, or B1 and B2
E. A1A3 and B1B3 have equal likelihoods
of harboring snapping shrimp species that can hybridize.
C
Rank the following from most general to most specific:
1.
gametic isolation
2. reproductive isolating mechanism
3.
sperm-egg incompatibility in sea urchins
4. prezygotic isolating
mechanism
A. 2, 3, 1, 4
B. 4, 1, 2, 3
C. 2, 1, 4,
3
D. 2, 4, 1, 3
E. 4, 2, 1, 3
D
In Europe, there is a long narrow hybrid zone, shown in red on the
map, between the high-altitude habitat of the yellow-bellied toad and
the lowland habitat of the fire-bellied toad. Despite this, there is
little gene flow between the two species. Select the correct
explanation.
A. Hybrids have poor survival and reproduction and
thus produce few viable offspring with members of either parent
species.
B. Toads mate only with their own kind in order to avoid
producing unhealthy hybrid young.
C. Yellow-bellied toads and
fire-bellied toads are two different species.
A
Among known plant species, which of these have been the two most
commonly occurring phenomena that have led to the origin of new
species?
1. allopatric speciation
2. sympatric
speciation
3. sexual selection
4. polyploidy
A. 2 and 4
B. 2 and 3
C. 1 and 4
D. 1 and 3
A
A hybrid zone is properly defined as
A/ a zone that includes the
intermediate portion of a cline.
B. a zone that features a
gradual change in species composition where two neighboring ecosystems
border each other.
C. an area where members of two closely
related species intermingle, but experience no gene flow.
D. an
area where two closely related species' ranges overlap.
E. an
area where mating occurs between members of two closely related
species, producing viable offspring.
E
According to the concept of punctuated equilibrium,
A. given
enough time, most existing species will gradually give rise to new
species.
B. transitional fossils, intermediate between newer
species and their parent species, should be abundant.
C. natural
selection is unimportant as a mechanism of evolution.
D. a new
species accumulates most of its unique features as it comes into
existence.
E. evolution of new species features long periods
during which changes are occurring, interspersed with short periods of
equilibrium, or stasis.
D
The question refers to the following evolutionary tree, whose
horizontal axis represents time (present time is on the far right) and
whose vertical axis represents morphological change.
Which of
these five species is the extant (i.e., not extinct) species that is
most closely related to species X, and why is this so?
A. Z;
shared a common ancestor with X most recently, and arose in the same
fashion as X
B. W; shared a common ancestor with X most
recently
C/ Y; arose in the same fashion (i.e., at the same
tempo) as X
D. V; shared a common ancestor with X most
recently
E. This tree does not provide enough information to
answer this question.
D
The question refers to the following description.
On the Bahamian island of Andros, mosquitofish populations live
in various, now-isolated, freshwater ponds that were once united.
Currently, some predator-rich ponds have mosquitofish that can swim in
short, fast bursts; other predator-poor ponds have mosquitofish that
can swim continuously for a long time. When placed together in the
same body of water, the two kinds of female mosquitofish exhibit
exclusive breeding preferences.
Which two of the following have operated to increase divergence
between mosquitofish populations on Andros?
1. improved gene
flow
2. bottleneck effect
3. sexual selection
4.
founder effect
5. natural selection
A. 3 and 4
B. 2 and 4
C. 2 and 3
D. 1 and
3
E. 3 and 5
E
Which of the following factors would not contribute to allopatric
speciation?
A. The isolated population is exposed to different
selection pressures than the ancestral population.
B. The
separated population is small, and genetic drift occurs.
C. Gene
flow between the two populations is extensive.
D. Different
mutations begin to distinguish the gene pools of the separated
populations.
E. A population becomes geographically isolated from
the parent population.
C
The next few questions refer to the following description.
On the volcanic, equatorial West African island of Sao Tomé, two
species of fruit fly exist. Drosophila yakuba inhabits the island's
lowlands, and is also found on the African mainland, located about 200
miles away. At higher elevations, and only on Sao Tomé, is found the
very closely related Drosophila santomea. The two species can
hybridize, though male hybrids are sterile. A hybrid zone exists at
middle elevations, though hybrids there are greatly outnumbered by D.
santomea. Studies of the two species' nuclear genomes reveal that D.
yakuba on the island is more closely related to mainland D. yakuba
than to D. santomea (2n = 4 in both species). Sao Tomé rose from the
Atlantic Ocean about 14 million years ago.
If the low number of hybrid flies in the hybrid zone, relative
to the number of D. santomea flies there, is due to the fact that
hybrids are poorly adapted to conditions in the hybrid zone, and if
fewer hybrid flies are produced with the passage of time, these
conditions will most likely lead to
A. stability.
B.
reinforcement.
C. fusion.
D. further speciation events.
B
You are confronted with a box of preserved grasshoppers of various
species that are new to science and have not been described. Your
assignment is to separate them into species. There is no accompanying
information as to where or when they were collected. Which species
concept will you have to use?
A. biological
B.
ecological
C. morphological
D. phylogenetic
C
Which of these should decline in hybrid zones where reinforcement is
occurring?
A. the genetic distinctness of two gene pools
B.
hybrid sterility
C. mutation rate
D. speciation
E. gene
flow between distinct gene pools
E
The original habitat of the North American maggot fly, Rhagoletis
pomonella, was native hawthorn trees. About 200 years ago, some
populations colonized newly introduced apple trees. The two
populations are still classified as subspecies, but sympatric
speciation is under way. What has contributed to incipient speciation
in the maggot fly?
A. Because apples mature more quickly than
hawthorn fruit, the apple-feeding flies have been selected for more
rapid development.
B. Maggot flies that feed and lay eggs on
apples have gradually become adapted to this fruit.
C. Apple
maggot flies try to avoid mating with hawthorn maggot flies.
A
Two animals are considered members of different species if they
_____.
A. live in different habitats
B. cannot mate and
produce viable, fertile offspring
C. look different
D. are
geographically isolated
E. are members of different populations
B
What is the most important factor that holds a gene pool of a species
together and prevents speciation?
A. behavioral isolation
B.
hybridization
C. gene flow
D. prezygotic barriers
E.
sexual selection
C
Which of the various species concepts distinguishes two species based
on the degree of genetic exchange between their gene pools?
A.
phylogenetic
B. morphological
C. ecological
D. biological
D
The difference between geographic isolation and habitat
differentiation is the
A. amount of genetic variation that occurs
among two gene pools as speciation occurs.
B. the ploidy of the
two populations as speciation occurs.
C. relative locations of
two populations as speciation occurs.
D. speed (tempo) at which
two populations undergo speciation.
E. identity of the
phylogenetic kingdom or domain in which these phenomena occur.
C
The question refers to the following description.
On the volcanic, equatorial West African island of Sao Tomé, two
species of fruit fly exist. Drosophila yakuba inhabits the island's
lowlands, and is also found on the African mainland, located about 200
miles away. At higher elevations, and only on Sao Tomé, is found the
very closely related Drosophila santomea. The two species can
hybridize, though male hybrids are sterile. A hybrid zone exists at
middle elevations, though hybrids there are greatly outnumbered by D.
santomea. Studies of the two species' nuclear genomes reveal that D.
yakuba on the island is more closely related to mainland D. yakuba
than to D. santomea (2n = 4 in both species). Sao Tomé rose from the
Atlantic Ocean about 14 million years ago.
If a speciation event occurred on Sao Tomé, producing D.
santomea from a parent colony of D. yakuba, then which terms
apply?
I. macroevolution
II allopatric speciation
III.
sympatric speciation
A. I only
B. II only
C. I and
II
D. I and III
D
Males of different species of the fruit fly Drosophila that live in
the same parts of the Hawaiian Islands have different elaborate
courtship rituals. These rituals involve fighting other males and
making stylized movements that attract females. What type of
reproductive isolation does this represent?
A. habitat
isolation
B. postzygotic barriers
C. gametic
isolation
D. behavioral isolation
E. temporal isolation
D
Dogs (Canis lupus familiaris) and gray wolves (Canis lupus) can
interbreed to produce viable, fertile offspring. These species shared
a common ancestor recently (in geologic time) and have a high degree
of genetic similarity, although their anatomies vary widely. Judging
from this evidence, which two species concepts are most likely to
place dogs and wolves together into a single species?
A.
biological and phylogenetic
B. biological and
morphological
C. morphological and phylogenetic
D.
ecological and morphological
E. ecological and phylogenetic
A
Rocky Mountain juniper (Juniperus scopulorum) and one-seeded juniper
(J. monosperma) have overlapping ranges. If pollen grains (which
contain sperm cells) from one species are unable to germinate and make
pollen tubes on female ovules (which contain egg cells) of the other
species, then which of these terms is applicable?
A. reduced
hybrid viability
B. behavioral isolation
C. hybrid
breakdown
D. mechanical isolation
D
According to the _____ model, evolution occurs in spurts; species
evolve relatively rapidly then remain unchanged for long
periods.
A. punctuated equilibrium
B. adaptive
radiation
C. gradualist
D. geographic isolation
E. nondisjunction
A
In a hypothetical situation, the National Park Service, which
administers Grand Canyon National Park in Arizona, builds a footbridge
over the Colorado River at the bottom of the canyon. The footbridge
permits migration to occur between populations of two closely related
antelope squirrels. Previously, one type of squirrel had been
restricted to the terrain south of the river, and the other type had
been restricted to terrain on the north side of the river. Immediately
before and ten years after the bridge's completion, researchers
collected ten antelope squirrels from both sides of the river, took
blood samples, and collected frequencies of alleles unique to the two
types of antelope squirrels (see the following graphs).
The data
in the previous graphs indicate that
A.some northern squirrels
migrated south, but no southern squirrels migrated north across the
bridge.
B. gene flow occurred from one type of squirrel into the
gene pool of the other type of squirrel.
C. two-way migration of
squirrels occurred across the bridge, but without
hybridization.
D. there was no migration between the two squirrel
populations after the bridge was completed.
E. a hybrid zone was
established after the completion of the bridge.
C
Select the correct statement describing sympatric speciation.
A.
Sympatric speciation can occur in a single generation.
B.
Sympatric speciation is always initiated by geographic isolation of
two populations.
C. Sympatric speciation has never been observed
in nature.
A
Theoretically, the production of sterile mules by interbreeding
between female horses (mares) and male donkeys (jacks) should
A.
eventually result in the formation of a single species from the two
parental species.
B. weaken the intrinsic reproductive barriers
between horses and donkeys.
C. strengthen postzygotic barriers
between horses and donkeys.
D. cause convergent
evolution.
E. result in the extinction of one of the two parental species.
C
Dog breeders maintain the purity of breeds by keeping dogs of
different breeds apart when they are fertile. This kind of isolation
is most similar to which of the following reproductive isolating
mechanisms?
A. hybrid breakdown
B. mechanical
isolation
C. gametic isolation
D. reduced hybrid
fertility
E. habitat isolation
E
The phenomenon of fusion is likely to occur when, after a period of
geographic isolation, two populations meet again and
A. a
decreasing number of viable, fertile hybrids is produced over the
course of generations.
B. an increasing number of viable, fertile
hybrids is produced over the course of generations.
C. the hybrid
zone is inhospitable to hybrid survival.
D. their chromosomes are
no longer homologous enough to permit meiosis.
E. a constant
number of viable, fertile hybrids is produced over the course of generations.
B
The question refers to the following description.
On the Bahamian island of Andros, mosquitofish populations live
in various, now-isolated, freshwater ponds that were once united.
Currently, some predator-rich ponds have mosquitofish that can swim in
short, fast bursts; other predator-poor ponds have mosquitofish that
can swim continuously for a long time. When placed together in the
same body of water, the two kinds of female mosquitofish exhibit
exclusive breeding preferences.
If one builds a canal linking a predator-rich pond to a
predator-poor pond, then what type(s) of selection should subsequently
be most expected among the mosquitofish in the original predator-rich
pond, and what type(s) should be most expected among the mosquitofish
in the formerly predator-poor pond?
A. less-intense disruptive
selection; more-intense disruptive selection
B. stabilizing
selection; stabilizing selection
C. less-intense directional
selection; more-intense directional selection
D. stabilizing
selection; directional selection
C
The question refers to the following description.
In the ocean, on either side of the Isthmus of Panama, are 30
species of snapping shrimp; some are shallow-water species, others are
adapted to deep water. There are 15 species on the Pacific side and 15
different species on the Atlantic side. The Isthmus of Panama started
rising about 10 million years ago. The oceans were completely
separated by the isthmus about 3 million years ago.
Why should deepwater shrimp on different sides of the isthmus
have diverged from each other earlier than shallow-water
shrimp?
A. The rise of the land bridge was accompanied by much
volcanic activity. Volcanic ash contains heavy metals, which are known
mutagens. Ash fall caused high levels of heavy metals in the ocean
sediments underlying the deep water, resulting in accelerated mutation
rates and faster divergence in deepwater shrimp.
B. Cold
temperatures, associated with deep water, have accelerated the
mutation rate, resulting in faster divergence in deepwater
shrimp.
C. They have been geographically isolated from each other
for a longer time.
D. Fresh water entering the ocean from tHe
canal is both less dense and cloudier than seawater. The cloudy fresh
water interferes with the ability of shallow-water shrimp to locate
mating partners, which reduces the frequency of mating, thereby
slowing the introduction of genetic variation.
C
According to the punctuated equilibria model,
A. most new
species accumulate their unique features relatively rapidly as they
come into existence, then change little for the rest of their duration
as a species.
B. speciation is usually due to a single
mutation.
C. given enough time, most existing species will branch
gradually into new species.
D. natural selection is unimportant
as a mechanism of evolution.
E. most evolution occurs in
sympatric populations.
A
Suppose that a group of male pied flycatchers migrated from a region
where there were no collared flycatchers to a region where both
species were present (see Figure 24.15 in your textbook). Assuming
events like this are very rare, which of the following scenarios is
least likely?
A. Pied females would rarely mate with collared
males.
B. The frequency of hybrid offspring would
decrease.
C. The frequency of hybrid offspring would
increase.
D. Migrant males would mate with collared females more
often than with pied females.
E. Migrant pied males would produce
fewer offspring than would resident pied males.
B
According to the phylogenetic species concept, what is a
species?
A. a clone of genetically identical organisms
B. a
set of organisms with a unique genetic history
C. a population
with a distinct fossil record
D. a population that is physically
able to mate even if there are no offspring or the offspring are
infertile
E. a population that interbreeds and produces fertile offspring
B
The most likely explanation for the high rate of sympatric speciation
that apparently existed among the cichlids of Lake Victoria in the
past is
A. introduction of a new predator.
B.
pollution.
C. sexual selection.
D. habitat
differentiation.
E. polyploidy.
C
The question refers to the following description.
On the volcanic, equatorial West African island of Sao Tomé, two
species of fruit fly exist. Drosophila yakuba inhabits the island's
lowlands, and is also found on the African mainland, located about 200
miles away. At higher elevations, and only on Sao Tomé, is found the
very closely related Drosophila santomea. The two species can
hybridize, though male hybrids are sterile. A hybrid zone exists at
middle elevations, though hybrids there are greatly outnumbered by D.
santomea. Studies of the two species' nuclear genomes reveal that D.
yakuba on the island is more closely related to mainland D. yakuba
than to D. santomea (2n = 4 in both species). Sao Tomé rose from the
Atlantic Ocean about 14 million years ago.
Which of the following reduces gene flow between the gene pools
of the two species on Sao Tomé, despite the existence of
hybrids?
A. a geographic barrier
B. hybrid
inviability
C. temporal isolation
D. hybrid
sterility
E. hybrid breakdown
D
What does the biological species concept use as the primary criterion
for determining species boundaries?
A. niche differences
B.
gene flow
C. morphological similarity
D. geographic
isolation
E. molecular (DNA, RNA, protein) similarit
B
The origin of a new plant species by hybridization, coupled with
accidents during cell division, is an example of
A. habitat
selection.
B. allopatric speciation.
C. sympatric
speciation.
D. autopolyploidy.
C
What is true of the flightless cormorants of the Galápagos
Islands?
A. They are close relatives of flightless cormorants
from the Americas.
B. They are descendants of the same common
ancestor that gave rise to the unique finches of these
islands.
C. Flightless cormorants on one island have restricted
gene flow with those on other islands, which could someday lead to a
macroevolutionary event.
D. If they are still able to breed
successfully with flying cormorants, it would probably be with North
American cormorants, rather than with South American
cormorants.
E. Their DNA has low levels of sequence homology with
the DNA of flying American cormorants.
C
The question refers to the following description.
On the volcanic, equatorial West African island of Sao Tomé, two
species of fruit fly exist. Drosophila yakuba inhabits the island's
lowlands, and is also found on the African mainland, located about 200
miles away. At higher elevations, and only on Sao Tomé, is found the
very closely related Drosophila santomea. The two species can
hybridize, though male hybrids are sterile. A hybrid zone exists at
middle elevations, though hybrids there are greatly outnumbered by D.
santomea. Studies of the two species' nuclear genomes reveal that D.
yakuba on the island is more closely related to mainland D. yakuba
than to D. santomea (2n = 4 in both species). Sao Tomé rose from the
Atlantic Ocean about 14 million years ago.
Using only the information provided in the paragraph, which of
the following is the best initial hypothesis for how D. santomea
descended from D. yakuba?
A. sexual selection
B.
allopolyploidy
C. autopolyploidy
D. geographic
isolation
E. habitat differentiation
E
On the volcanic, equatorial West African island of Sao Tomé, two
species of fruit fly exist. Drosophila yakuba inhabits the island's
lowlands, and is also found on the African mainland, located about 200
miles away. At higher elevations, and only on Sao Tomé, is found the
very closely related Drosophila santomea. The two species can
hybridize, though male hybrids are sterile. A hybrid zone exists at
middle elevations, though hybrids there are greatly outnumbered by D.
santomea. Studies of the two species' nuclear genomes reveal that D.
yakuba on the island is more closely related to mainland D. yakuba
than to D. santomea (2n = 4 in both species). Sao Tomé rose from the
Atlantic Ocean about 14 million years ago.
The observation that island D. yakuba are more closely related
to mainland D. yakuba than island D. yakuba are to D. santomea is best
explained by proposing that D. santomea
A. descended from an
original colony of D. yakuba, of which there are no surviving members.
The current island D. yakuba represent a second colonization event
from elsewhere.
B. descended from a now-extinct, non-African
fruit fly.
C. arrived on the island before D. yakuba.
D.
descended from a single colony of D. yakuba, which had been introduced
from elsewhere, with no subsequent colonization events.
A
The question refers to the following evolutionary tree, whose
horizontal axis represents time (present time is on the far right) and
whose vertical axis represents morphological change.
Which
conclusion can be drawn from this evolutionary tree?
A.
Gradualistic speciation and speciation involving punctuated
equilibrium are mutually exclusive concepts; only one of them can
occur.
B.Eldredge and Gould would deny that the lineages labeled
X, Y, and Z could represent true species.
C. V and W shared a
common ancestor more recently than any of the other species.
D.
Assuming that the tip of each line represents a species, there are
five extant (i.e., not extinct) species resulting from the earliest
common ancestor.
E. A single clade (i.e., a group of species that
share a common ancestor) can exhibit both gradualism and punctuated equilibri
E
What is true of macroevolution?
A/ It is defined as the
evolution of microscopic organisms into organisms that can be seen
with the naked eye.
B. It is evolution above the species
level.
C. It is the same as microevolution, but includes the
origin of new species.
D. It is defined as a change in allele or
gene frequency over the course of many generations.
E. It is the
conceptual link between irritability and adaptation.
B
On the Bahamian island of Andros, mosquitofish populations live in
various, now-isolated, freshwater ponds that were once united.
Currently, some predator-rich ponds have mosquitofish that can swim in
short, fast bursts; other predator-poor ponds have mosquitofish that
can swim continuously for a long time. When placed together in the
same body of water, the two kinds of female mosquitofish exhibit
exclusive breeding preferences.
The predatory fish rely on visual cues and speed to capture
mosquitofish. Mosquitofish rely on speed and visual cues to avoid the
predatory fish. Which adaptation(s) might help the predators survive
in ponds that are home to faster mosquitofish?
1. directional
selection for increased speed
2. stabilizing selection for speed
that matches that of the mosquitofish
3. change in hunting
behavior that replaces reliance on visual cues with reliance on
tactile cues, which can be used to hunt at night
4. change in
hunting behavior that eliminates speed in favor of better camouflage,
which permits an ambush strategy
A. 1 only
B. 2 only
C.
either 1 or 3
D. either 2 or 3
E. 1, 3, or 4
E
Which of the following statements about species, as defined by the
biological species concept, is (are) correct?
I. Biological
species are defined by reproductive isolation.
II. Biological
species are the model used for grouping extinct forms of
life.
III. The biological species is the largest unit of
population in which successful interbreeding is possible.
A. I
and II
B. I and III
C. II and III
D. I, II, and III
B
Speciation
A. must begin with the geographic isolation of a
small, frontier population.
B. occurs at such a slow pace that no
one has ever observed the emergence of new species.
C. and
macroevolution are synonymous.
D. can involve changes to a single
gene.
E. occurs only by the accumulation of genetic change over
vast expanses of time.
D
Adaptive radiations on archipelagos (island chains) represent some of
the best-understood speciation events. Why is an ancestral species
more likely to give rise to multiple descendent species on an
archipelago than on an equal-sized area of mainland?
A.
Populations on nearby islands are more likely to be genetically
isolated than populations that are equally close to one another on the
mainland.
B. By chance, different species will colonize different
islands in a chain.
C. Favorable mutations are more likely to
arise on an archipelago as populations try to adapt to conditions on
their specific island.
A
Two species of frogs belonging to the same genus occasionally mate,
but the offspring fail to develop and hatch. What is the mechanism for
keeping the two frog species separate?
A. the postzygotic barrier
called hybrid breakdown
B. the prezygotic barrier called hybrid
sterility
C. the postzygotic barrier called hybrid
inviability
D. gametic isolation
C
A narrow hybrid zone separates the toad species Bombina bombina and
Bombina variegata. What is true of those alleles that are unique to
the parental species?
A. Such alleles should be absent.
B.
The alleles' heterozygosity should be higher among the hybrid toads
there.
C. Their allele frequency should be nearly the same as the
allele frequencies in toad populations distant from the hybrid
zone.
D. Their allele frequency on one edge of the hybrid zone
should roughly equal their frequency on the opposite edge of the
hybrid zone.
B
In order for speciation to occur, what must be true?
A/ Large
numbers of genes that affect numerous phenotypic traits must
change.
B. Large numbers of genes that affect a single phenotypic
trait must change.
C. The number of chromosomes in the gene pool
must change.
D. At least one gene, affecting at least one
phenotypic trait, must change.
E. Changes to centromere location
or chromosome size must occur within the gene pool.
D
Beetle pollinators of a particular plant are attracted to its
flowers' bright orange color. The beetles not only pollinate the
flowers, but they mate while inside of the flowers. A mutant version
of the plant with red flowers becomes more common with the passage of
time. A particular variant of the beetle prefers the red flowers to
the orange flowers. Over time, these two beetle variants diverge from
each other to such an extent that interbreeding is no longer possible.
What kind of speciation has occurred in this example, and what has
driven it?
A. sympatric speciation; allopolyploidy
B.
sympatric speciation; sexual selection
C. sympatric speciation;
habitat differentiation
D. allopatric speciation; ecological
isolation
E. allopatric speciation; behavioral isolation
C
There is still some controversy among biologists about whether
Neanderthals should be placed within the same species as modern humans
or into a separate species of their own. Most DNA sequence data
analyzed so far indicate that there was probably little or no gene
flow between Neanderthals and Homo sapiens. Which species concept is
most applicable in this example?
A. ecological
B.
morphological
C. biological
D. phylogenetic
C
Which of these is an example of temporal isolation?
A. One
species is found only in New York, the other only in London.
B.
One is a type of primate, the other is a type of marsupial.
C.
One species performs a specific courtship dance. the other species
does not.
D. One species is nocturnal, and the other species is
not.
E. The average weight of the individuals in one species is
45 kg; in the other species the average is 290 kg.
D
In the ocean, on either side of the Isthmus of Panama, are 30 species
of snapping shrimp; some are shallow-water species, others are adapted
to deep water. There are 15 species on the Pacific side and 15
different species on the Atlantic side. The Isthmus of Panama started
rising about 10 million years ago.
In the following figure, the isthmus separates the Pacific Ocean
on the left (side A) from the Atlantic Ocean on the right (side B).
The seawater on either side of the isthmus is separated into five
depth habitats (15), with 1 being the shallowest.
There are currently two, large, permanent bridges that span the
Panama Canal. The bridges are about 8 miles apart. If snapping shrimp
avoid swimming at night and avoid swimming under shadows, then what do
these bridges represent for the snapping shrimp?
A. sources of a
hybrid zone between the two bridges
B. sources of refuge
C.
geographic barriers
D. sources for increased gene flow
C
The most likely explanation for the recent decline in cichlid species
diversity in Lake Victoria is
A/ stability.
B.
reinforcement.
C. geographic isolation.
D. fusion.
E. polyploidy.
D
The largest unit within which gene flow can readily occur is
a
A. species.
B. genus.
C. population.
D.
hybrid.
E. phylum.
A