Deck 22: The Origin of Species

Question 1

Which of the following reproductive types of isolation illustrates postzygotic barriers?

A)habitat isolation
B)mechanical isolation
C)temporal isolation
D)hybrid breakdown

Answer 1

D

Question 2

Which of the following criteria used in classification is the most easily evaluated by the observer?

A)morphology
B)biochemistry
C)physiology
D)DNA sequence

Answer 2

A

Question 3

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)ecological and phylogenetic
B)morphological and phylogenetic
C)biological and morphological
D)biological and phylogenetic

Answer 3

D

Question 4

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,reduced hybrid viability
B)the postzygotic barrier,hybrid breakdown
C)the prezygotic barrier,reduced hybrid fertility
D)the prezygotic barrier,gametic isolation

Question 5

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 interbreeding between Neanderthals and humans;however,it appears to have been limited and mostly unidirectional (Neanderthal genes are present in Homo sapiens DNA,but there exists little to no evidence of the DNA of Homo sapiens in the small number of genomes sequenced from Neanderthal fossils.Which species concept is most applicable as a method of analysis in this example?

A)phylogenetic
B)ecological
C)morphological
D)biological

Question 6

You are an undergraduate student working with a graduate student in an entomology lab,and she presents you with a box of preserved grasshoppers of various species that are new to science and have not been described.Your assignment is to help her 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)phylogenetic
C)ecological
D)morphological

Question 7

When the only evidence available for two extinct species is their fossil record,evaluation of reproductive isolation and the biological species concept is not useful.However,the phylogenetic species concept could potentially differentiate the species by using evolutionary history to describe

A)morphology traits shared by the smallest group of individuals of each species that share a common ancestor.
B)the ecological niches of each,interacting with living and nonliving parts of their environment.
C)their gametic compatibility.
D)their temporal isolation.

Question 8

In a hypothetical situation,a certain species of flea feeds only on the blood of pronghorn antelopes.In rangelands of the western United States,pronghorns and cattle often associate with one another.If some of these pronghorn-feeding 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

Question 9

Among known plant species,which of these are 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)1 and 3 only
B)1 and 4 only
C)2 and 3 only
D)2 and 4 only

Question 10

The origin of a new plant species by hybridization,coupled with accidents during cell division,is an example of

A)allopatric speciation.
B)sympatric speciation.
C)autopolyploidy.
D)habitat selection.

Question 11

Imagine two species of snakes that live in a tropical rain forest of Malaysia do not typically interbreed.In nature,one species is ground-dwelling and feeds mainly on insects and small amphibians near water,whereas the other snake feeds in the lower to mid-canopy of trees and vines rising from the forest floor.However,at a zoo in Singapore where they were kept in the same gallery exhibit,the two species were observed interbreeding and produced viable offspring.Which of the following reproductive barriers is most likely preventing these species from interbreeding in the forest?

A)reduced hybrid viability
B)habitat isolation
C)a postzygotic barrier
D)mechanical isolation
E)gametic isolation

Question 12

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)sexual selection.
B)habitat differentiation.
C)polyploidy.
D)pollution.
E)introduction of a new predator.

Question 13

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 only
B)2 and 4 only
C)1,3,and 6 only
D)2,4,and 5 only
E)1,2,5,and 6 only

Question 14

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 models 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 only
B)I and III only
C)II and III only
D)I,II,and III

Question 15

Which of the following correctly describes,or is an example of,habitat isolation?

A)Members of different frog species never come in contact due to a difference in mating season.
B)Members of different bird species never come in contact due to differences in their songs or mating calls.
C)Members of the same species never come in contact due to a geographic barrier to interbreeding.
D)Morphological features such as size or incompatible genitalia prevent interbreeding.
E)Members of different plant species are in flower at different times of the season,minimizing interbreeding.

Question 16

A species is represented by individuals that form a population

A)whose members have the ability to interbreed and produce viable,fertile offspring.
B)whose members have the ability to interbreed but do not produce viable offspring.
C)but are reproductively incompatible.
D)but are distinct biological species that live in the same area.

Question 17

Macroevolution occurs

A)only when reproductive barriers,either pre- or post-zygotic,prevent all gene flow between two populations.
B)when reproductive barriers,either pre- or post-zygotic,genetically isolate species,even in the presence of some gene flow between two populations.
C)when species populations undergo changes in allele frequencies over time.
D)when species morphology from genetic change causes their physical similarity to drift apart.

Question 18

Which of the following statements about speciation is correct?

A)The end result of natural selection is always speciation.
B)Natural selection chooses the reproductive barriers for populations.
C)It always takes millions of years for speciation to occur.
D)Speciation is a basis for understanding macroevolution.

Question 19

Imagine a male dragonfly is flying around in an aggressive pattern to find an appropriate mate in a wetland with many species of dragonflies and damselflies.Finally,he spots a female dragonfly that appears to be of the same species,based on her flight behavior and color,and the two mate.The sperm of the male,however,are unable to fertilize the eggs of the female when she lays them because her egg cell membrane proteins and carbohydrates do not recognize and bind to the male's sperm.This is an example of

A)reduced hybrid viability.
B)behavioral isolation.
C)a postzygotic barrier.
D)mechanical isolation.
E)gametic isolation.

Question 20

Microevolution occurs

A)only when reproductive barriers,either pre- or post-zygotic,prevent all gene flow between two populations.
B)when species diverge.
C)when species populations undergo changes in allele frequencies over time.
D)when reproductive barriers,either pre- or post-zygotic,genetically isolate species to the point where they no longer interbreed to produce viable offspring.

Question 21

Which of these should decline in hybrid zones where reinforcement is occurring?

A)gene flow between distinct gene pools
B)speciation
C)the genetic distinctness of two gene pools
D)mutation rate
E)hybrid sterility

Question 22

Which of these phrases describes a stable hybrid zone?

A)obstacle to gene flow
B)reduced hybrid viability
C)reduced hybrid fertility
D)continued production of hybrid individuals

Question 23

Which of the following statements is most accurate?

A)Biological reproductive barriers always occur after physical separation of populations.
B)Biological reproductive barriers occur as a direct result of geographic isolation of populations.
C)Geographic separation may result in biological barriers over time if populations of a species in the newly isolated regions undergo selective pressures that promote biological isolation and prevent successful reproduction if the species were to again come into contact later.
D)Biological reproductive barriers may prevent successful interbreeding even when geographic isolation has occurred,and two populations do not come into contact with each other.

Question 24

"Conventional wisdom holds that the development of separate species happens quickly,most often when populations become separated by a geographical barrier." This is called ________ speciation."Even if these groups meet again and manage to mate before diverging too far from one another,their offspring will be unfit and die out." This is described as hybrid ________.

A)sympatric;viability
B)allopatric;fertility
C)sympatric;breakdown
D)allopatric;breakdown

Question 25

Which of the following descriptions of polyploidy indicate speciation?

A)An accident during cell division results in an extra set of chromosomes.
B)An individual has more than two chromosome sets from a single species.
C)Two different species interbreed and produce hybrid offspring.
D)Allopolyploids mate with each other but cannot interbreed with parent species.

Question 26

You find a plant that is larger than others in your wheat field.When you examine the chromosomes of this plant during cell division,you observe that the cells have double chromosome numbers of the other wheat plants.You conclude this is an autopolyploid plant representing a new biological species in your wheat field when you observe

A)fertile tetrapods produced by self-pollinating.
B)production of hybrid organisms.
C)allopolyploids interbreeding with parents.
D)ancestral sterile plants.

Question 27

Which of the following processes occurs first in order to begin speciation?

A)single gene change
B)formation of mechanical barrier to reproduction
C)postzygotic hybrid sterility in Drosophila
D)interruption of gene flow between two populations

Question 28

Sexual selection in cichlids occurs by female mate choice and results in reproductive isolation when

A)subpopulations exploit a habitat not used by the parent population.
B)under normal light,each species prefers males of their own species.
C)all species have extra sets of chromosomes.
D)under orange light,each species prefers orange mates.

Question 29

More species tend to be found in regions subdivided by rivers,canyons,mountains,or other human-induced barriers because of

A)geographic isolation.
B)absence of geographic isolation.
C)gene flow.
D)gene drift.

Question 30

How can reproductive barriers form between sympatric populations while their members stay in contact with them?

A)increased gene flow
B)increased polyploidy
C)decreased habitat differentiation
D)decreased sexual selection

Question 31

A hybrid zone is properly defined as

A)an area where two closely related species' ranges overlap.
B)an area where mating occurs between members of two closely related species,producing viable offspring.
C)a zone that features a gradual change in species composition where two neighboring ecosystems border each other.
D)a zone that includes the intermediate portion of a cline.
E)an area where members of two closely related species co-inhabit but experience no gene flow.

Question 32

Evolution of a new species can occur

A)as a result of individuals acquiring mutations in reaction to environmental changes in their surroundings.
B)only over many generations of a species.
C)only if species are separated geographically.
D)in two populations of a species over as little as one generation,even if they are not reproductively,biologically,or geographically isolated.

Question 33

After geographic separation,what process would be the last step before reproductive isolation?

A)gene pool divergence
B)mutation
C)natural selection
D)genetic drift

Question 34

In the ocean,on either side of the Isthmus of Panama,are 30 species of snapping shrimp;some are shallow-water species,and 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)They have been geographically isolated from each other for a longer time.
B)Cold temperatures,associated with deep water,have accelerated the mutation rate,resulting in faster divergence in deepwater shrimp.
C)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.
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.

Question 35

The form of speciation that requires the emergence of a reproductive barrier that isolates a subset of a population from the remainder of the population in the same area is

A)allopatric.
B)sympatric.
C)reduced hybrid fertility.
D)geographic isolation.

Question 36

Which one of the following choices describes an advantage of the biological species concept?

A)lack of methodology to evaluate fossil reproduction
B)does not apply to organisms that reproduce asexually
C)overemphasizes absence of gene flow
D)describes speciation by the evolution of reproductive isolation

Question 37

The most likely explanation for the recent decline in cichlid species diversity in Lake Victoria is

A)reinforcement.
B)fusion.
C)stability.
D)geographic isolation.

Question 38

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)Their allele frequency should be nearly the same as the allele frequencies in toad populations distant from the hybrid zone.
C)The alleles' heterozygosity should be higher among the hybrid toads there.
D)Their allele frequency on one edge of the hybrid zone should be roughly equal to their frequency on the opposite edge of the hybrid zone.

Question 39

Imagine a very large volcanic eruption occurs,and a 20 km-wide lava flow moves into a valley and separates it into two halves.How might this affect resident species with regard to allopatric speciation?

A)The lava flow area will cause a geographic barrier that promotes speciation among the majority of species populating the area.
B)The effect of the lava flow on allopatric speciation will depend on the identity and traits of the various species present,including their abundance and respective mobility within the valley.
C)The effects of the lava flow on speciation will depend on to what extent the various individuals present at the time can adapt to the new lava in the environment.
D)The lava flow will not cause much allopatric speciation to populations in the area because species that are present will be able to move across and around the lava flow.

Question 40

Which mechanism would reverse speciation?

A)increased gene flow
B)gene pools of the two species becoming increasingly different
C)increased ability of females to discriminate mates
D)decreased production of hybrids

Question 41

If a speciation event occurred on Sao Tomé,producing D.santomea from a parent colony of D.yakuba,then which of the following terms applies (apply)?
I)macroevolution
II allopatric speciation
III)sympatric speciation

A)I only
B)II only
C)I and II
D)I and III

Question 42

Figure 22.6
A hybrid zone is indicated by plotting the frequency of the yellow-belly allele across the distance from the center of the hybrid zone.What is the gene frequency of the fire-bellied toad 20 km from the hybrid zone center?

A)1
B)0
C)0)1
D)10

Question 43

The following questions refer to the evolutionary tree in Figure 22.4,whose horizontal axis represents time (present time is on the far right)and whose vertical axis represents morphological change.
Figure 22.4
Which of these five species is the extant (that is,not extinct)species that is most closely related to species X,and why is this so?

A)V;shared a common ancestor with X most recently
B)W;shared a common ancestor with X most recently
C)Y;arose before X
D)Z;shared a common ancestor with X

Question 44

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)behavioral isolation
B)mechanical isolation
C)hybrid breakdown
D)reduced hybrid viability

Question 45

Please use the following information to answer the questions below.
In the ocean,on either side of the Isthmus of Panama,are 30 species of snapping shrimp;some are shallow-water species,and 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 Figure 22.1,the isthmus separates the Pacific Ocean on the left (side 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.
Figure 22.1
In which habitat should you find snapping shrimp most closely related to shrimp that live in habitat A4?

A)A3
B)A5
C)B4
D)either A3 or A5
E)any species from any one of the side A habitats

Question 46

Speciation

A)occurs at such a slow pace that no one has ever observed the emergence of new species.
B)occurs only by the accumulation of genetic change over vast expanses of time.
C)must begin with the geographic isolation of a small,frontier population.
D)occurs when one species splits into two or more species.

Question 47

Which factor is most important for explaining why there are equal numbers of snapping shrimp species on either side of the isthmus?

A)the relative shortness of time they have been separated
B)the depth of the ocean
C)the number of actual depth habitats between the surface and the sea floor
D)the elevation of the isthmus above sea level
E)the depth of the canal

Question 48

The following questions refer to the evolutionary tree in Figure 22.4,whose horizontal axis represents time (present time is on the far right)and whose vertical axis represents morphological change.
Figure 22.4
Which species is most closely related to species W?

A)V is most closely related to species W.
B)X is most closely related to species W.
C)Y and Z are equally closely related to W.

Question 49

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 10 years after the bridge's completion,researchers collected 10 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 graphs in Figures 22.2 and 22.3). Figure 22.2
Figure 22.3
The data in these graphs indicate that

A)a hybrid zone was established after the completion of the bridge.
B)there was no migration between the two squirrel populations after the bridge was completed.
C)gene flow occurred from one type of squirrel into the gene pool of the other type of squirrel.
D)two-way migration of squirrels occurred across the bridge,but without hybridization.
E)some northern squirrels migrated south,but no southern squirrels migrated north across the bridge.

Question 50

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)A1-A3 and B1-B3 have equal likelihoods of harboring snapping shrimp species that can hybridize.

Question 51

The following questions refer to the evolutionary tree in Figure 22.4,whose horizontal axis represents time (present time is on the far right)and whose vertical axis represents morphological change.
Figure 22.4
Which of these five species originated earliest and appeared suddenly in the fossil record?

A)V
B)W
C)X
D)Y
E)Z

Question 52

Please use the following information to answer the questions below.
In the ocean,on either side of the Isthmus of Panama,are 30 species of snapping shrimp;some are shallow-water species,and 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 Figure 22.1,the isthmus separates the Pacific Ocean on the left (side 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.
Figure 22.1
Which of these habitats is likely to harbor the youngest species?

A)A5
B)B4
C)A3
D)B2
E)A1

Question 53

The mechanism of macroevolution occurs by

A)multiple acts of speciation on an ancestral organism.
B)continuation of gene flow between populations.
C)weakening of barriers to reproductive isolation.
D)appearing in the fossil record of species with similar morphologies.

Question 54

Please use the following information to answer the questions below.
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)hybrid breakdown
B)hybrid inviability
C)hybrid sterility
D)temporal isolation
E)a geographic barrier

Question 55

The following questions refer to the evolutionary tree in Figure 22.4,whose horizontal axis represents time (present time is on the far right)and whose vertical axis represents morphological change.
Figure 22.4
Which species is least expected to have a good record of transitional fossils;in other words,which species' fossils,if present at all,are expected only in relatively superficial (that is,shallow)strata?

A)V
B)W
C)X
D)Y
E)Z

Question 56

Figure 22.5
Which of the following is evidence for allopatric speciation by the formation of the Isthmus of Panama?

A)One species of the sister species lives on the Pacific side.
B)Genetic analyses indicate time of origin.
C)Sister species diverge first.
D)Coordination of geological evidence demonstrated species divergence.

Question 57

Which habitats should harbor snapping shrimp species with the greatest degree of genetic divergence from each other?

A)A1 and A5
B)A1 and B5
C)B5 and B1
D)A5 and B5
E)Both A1/A5 and B1/B5 should have the greatest,but equal amounts of,genetic divergence.

Question 58

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 refuge
B)geographic barriers
C)sources of a hybrid zone between the two bridges
D)sources for increased gene flow

Question 59

Figure 22.7
Two models for the speed of speciation are based on patterns in the fossil record.Which of the following statements describes the gradual model of evolution?

A)Species steadily diverge from one another.
B)New species change suddenly.
C)Periods of stasis are punctuated by change.
D)There is absence of intermediate fossils.

Question 60

The following questions refer to the evolutionary tree in Figure 22.4,whose horizontal axis represents time (present time is on the far right)and whose vertical axis represents morphological change.
Figure 22.4
Which conclusion can be drawn from this evolutionary tree?

A)Gradualistic speciation and speciation involving punctuated equilibrium are mutually exclusive concepts.
B)Eldredge and Gould would deny that the lineages labeled X,Y,and Z could represent true species.
C)Assuming that the tip of each line represents a species,there are five extant (that is,not extinct)species resulting from the earliest common ancestor.
D)A single clade (that is,a group of species that share a common ancestor)can exhibit both gradualism and punctuated equilibrium.

Question 61

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)14.
B)16.
C)28.
D)56.

Question 62

Which of these evolutionary trees represents the situation described in the paragraph? (Note: D.yakuba (I)represents the island population,and D.yakuba (M)represents the mainland population. )

A)

B)

C)

D)

Question 63

The largest unit within which gene flow can readily occur is a

A)population.
B)species.
C)genus.
D)hybrid.

Question 64

Which of the following factors would not contribute to allopatric speciation?

A)A population becomes geographically isolated from the parent population.
B)The separated population is small,and genetic drift occurs.
C)The isolated population is exposed to different selection pressures than the ancestral population.
D)Gene flow between the two populations is extensive.

Question 65

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 a now-extinct non-African fruit fly.
B)arrived on the island before D.yakuba.
C)descended from a single colony of D.yakuba,which had been introduced from elsewhere,with no subsequent colonization events.
D)descended from an original colony of D.yakuba,of which there are no surviving members.

Question 66

Please use the following information to answer the questions below.
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)1 and 3 only
B)2 and 3 only
C)2 and 4 only
D)3 and 4 only
E)3 and 5 only

Question 67

According to the punctuated equilibria model,

A)natural selection is unimportant as a mechanism of evolution.
B)given enough time,most existing species will branch gradually into new species.
C)most evolution occurs in sympatric populations.
D)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.

Question 68

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)Build a canal linking the two ponds that permits free movement of mosquitofish but not of predators.
B)Transfer only female mosquitofish from a predator-rich pond to a predator-poor pond.
C)Perform a reciprocal transfer of females between predator-rich and predator-poor ponds.
D)Remove predators from a predator-rich pond and transfer them to a predator-poor pond.

Question 69

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
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)1,3,or 4

Question 70

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)fusion.
B)reinforcement.
C)stability.
D)further speciation events.

Question 71

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)temporal isolation
C)behavioral isolation
D)gametic isolation

Question 72

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)geographic isolation
B)autopolyploidy
C)habitat differentiation
D)sexual selection
E)allopolyploidy

Question 73

Bird guides once listed the myrtle warbler and Audubon's warbler as distinct species.Recently,these birds have been reclassified 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 interbreed often in nature,and their offspring survive and reproduce well.
B)The two forms live in similar habitats and have similar food requirements.
C)The two forms have many genes in common.
D)The two forms are very similar in coloration.

Question 74

Please use the following information to answer the questions below.
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)behavioral isolation
B)habitat isolation
C)temporal isolation
D)mechanical isolation
E)gametic isolation

Question 75

If you build a canal linking a predator-rich pond to a predator-poor pond,then what type of selection should subsequently be most expected among the mosquitofish in the original predator-rich pond,and what type should be most expected among the mosquitofish in the formerly predator-poor pond?

A)stabilizing selection;directional selection
B)stabilizing selection;stabilizing selection
C)less-intense directional selection;more-intense directional selection
D)less-intense disruptive selection;more-intense disruptive selection