Deck 19: Speciation and the Origins of Biological Diversity

Question 1

In many predator-prey relationships, evolutionary change in the prey will result in evolutionary change in the predator, a phenomenon known as

A)polyploidy.
B)allopatrism.
C)coevolution.
D)sympatric speciation.

Answer 1

C

Question 2

A farmer sprays a field with an herbicide that kills most of the weeds he finds. Could the weeds develop resistance to the herbicide over the course of a growing season?

A)Yes; the herbicide will induce mutations that create resistance alleles.
B)Yes; if the weeds have enough genetic variation, they can evolve rapidly through natural selection.
C)No; the process of evolution is very slow. The evolution of herbicide resistance would take thousands of years.
D)No; in order to develop resistance, the weeds would have to hybridize with a plant that is already resistant to the herbicide.

Answer 2

B

Question 3

A flower is red, has a long tube formed by fusion of petals, has nectar at the base of the tube, has no landing platform, and opens during the day. It has probably become adapted to mate with the assistance of

A)mice.
B)bees.
C)hummingbirds.
D)bats.

Answer 3

C

Question 4

For the quality of an adaptation to improve over time, _____ must already exist within the population.

A)genetic limitations
B)genetic variation
C)speciation
D)ecological trade-offs

Question 5

A population of crickets in Hawaii exhibits an allele that changes the shape of its wings so that they cannot chirp. Chirping crickets are targeted by parasitic wasps that eventually kill the cricket, but nonchirping crickets have trouble finding their mates. This is an example of

A)reproductive isolation.
B)speciation.
C)a prezygotic barrier.
D)an ecological trade-off.

Question 6

Which of the following is not true of adaptations?

A)They are often complex.
B)They help organisms better match their environments.
C)They can occur quickly or slowly.
D)They lead to an organism becoming perfectly adapted.

Question 7

Every year, environmental signals in Africa cause flycatchers to return to the Netherlands to breed. When they arrive, they depend on freshly hatched caterpillars for food. Global climate change has caused the caterpillars to hatch earlier in the Netherlands, but the environmental cues in Africa remain the same. Now, when the flycatchers return to the Netherlands the caterpillars are no longer available as a food source. Which of the following is likely to happen to this species of flycatcher?

A)Flycatchers will adapt to environmental change because alleles that cause flycatchers to recognize earlier environmental signals in Africa will increase in frequency in flycatcher populations.
B)Flycatchers will adapt to environmental change because alleles that aid flycatchers in utilizing other food sources (besides caterpillars) will increase in frequency in flycatcher populations.
C)Flycatchers will not adapt to environmental change because their population does not have alleles that aid in survival under these conditions.
D)All of the above are possible scenarios.

Question 8

Some species of orchids attract wasps to assist them in reproduction by producing flowers that look like female wasps. The flowers fool male wasps into attempting to mate with them. As a result, the wasp is covered with pollen that it takes with it to the next flower it attempts to mate with. This example shows adaptive evolution by

A)the orchids.
B)the wasps.
C)all flowering plants.
D)ancestral wasps.

Question 9

The soapberry bugs shown in the figure below adapted to a change in food source in as fast as 30 years. For evolution to occur this quickly

A)alleles for shorter beaks must have been present in the soapberry bug population before its food source changed.
B)the soapberry bugs must have mutated their beak length genes when they ran out of food.
C)the life cycle of the soapberry bug (time from egg hatching to reproductive age) must be very long.
D)soapberry bugs must have had several other food sources besides the fruit they normally ate.

Question 10

Adaptive evolution allows species to

A)reduce mutation rate.
B)decrease genetic variation.
C)adjust to environmental changes.
D)hybridize.

Question 11

The faster a cheetah can run, the more likely it is to capture its prey. Cheetahs with longer legs are able to run faster than those with shorter legs. Although the existing cheetah population shows a variety of leg lengths, cheetah legs are not continuing to increase in length from one generation to the next. Which of the following is a possible explanation?

A)The genes that are involved in cheetah leg length do not undergo mutation.
B)Cheetahs with long legs are reproductively isolated from cheetahs with short legs.
C)Natural selection does not act on traits involved in predation.
D)Longer cheetah leg bones are more likely to break.

Question 12

Populations of weaver ants work together to "sew" leaves into a living nest that acts as a protective shelter for the entire population. The nest-building behavior of weaver ants

A)illustrates that the ants can consciously plan their nests.
B)represents a complex behavioral adaptation.
C)shows that these ants can get along without interacting with other species.
D)illustrates that adaptive evolution is goal oriented.

Question 13

Adaptive evolution

A)is large-scale movement of a single species over a new geographic area.
B)occurs when a more adapted species causes the extinction of a less adapted one.
C)is the process by which natural selection improves the match between an organism and its environment over time.
D)is an increase in the adaptiveness of many species that have already evolved.

Question 14

The Eastern skunk cabbage, which blooms in very early spring, produces chemicals that smell like decaying meat. This plant has probably become adapted to mate with the assistance of

A)butterflies.
B)honeybees.
C)flies.
D)wind.

Question 15

When a brightly colored guppy population is placed in an area containing many predators, the population changes in only a few generations to one containing only guppies with drab, dull colors that blend into their environment. This is an example of how natural selection can

A)force new color mutations to occur.
B)convert a dominant allele into a recessive allele.
C)improve the match between guppies and their environment.
D)change the color preferences of female guppies.

Question 16

The rough-skinned newt produces one of the most potent toxins on the planet. Scientists in Oregon have found that as newts evolve to produce a more deadly toxin, their primary predator, the garter snake, evolves ways to resist the toxin. This is an example of

A)ecological trade-offs in the evolution of the newt.
B)an adaptation of the newt to living in aquatic environments.
C)reproductive isolation in a population of garter snakes.
D)coevolution of predator and prey.

Question 17

Which of the following is not true?

A)Adaptations are complex and always predesigned.
B)Some adaptations are so complex that they may appear to be predesigned.
C)Adaptations often involve more than a single characteristic of organisms.
D)Some adaptations help organisms defend against predators.

Question 18

Which of the following is responsible for the nearly perfect match in color pattern between a species of praying mantis (an insect)and the leaves on which it rests?

A)genetic drift
B)adaptive evolution
C)the Hardy-Weinberg equation
D)speciation

Question 19

Which of the following most likely is not an adaptation by plants to attract animals for assistance with mating?

A)production of nectar
B)brightly colored flower petals
C)absence of petals
D)sweet-smelling fragrance

Question 20

If a population lacks genetic variation,

A)it may not be able to evolve as the environment changes.
B)it is more likely to undergo gene flow.
C)reproductive isolation is unlikely.
D)the rate of speciation may increase.

Question 21

Before the cultivation of the apple tree, apple maggot flies laid their eggs exclusively on the fruit of Hawthorne trees. As apple orchards became more prominent, apple maggot flies began to lay their eggs on both the fruit of the Hawthorne tree and the fruit of cultivated apple trees. Now, apple maggot flies that live on apple trees mate and lay their eggs at different times of the year than apple maggot flies that live on Hawthorne trees. Is this an example of reproductive isolation?

A)Yes; these two fly populations exhibit a postzygotic barrier that prevents hybrid individuals from developing properly.
B)No; although these two fly populations do not mate in nature, they can be forced to mate in a laboratory because their DNA sequences are still the same.
C)No; this is an example of speciation rather than reproductive isolation.
D)Yes; these two fly populations exhibit a behavioral prezygotic barrier that prevents their gametes from encountering each other.

Question 22

In the figure below, two populations of one species of fruit flies were raised for several generations on different nutrients (starch and maltose). Then the members of the two populations were reintroduced and the mating frequencies of flies from the two different populations were recorded. Which of the following is true?

A)After only a few generations, these two populations have undergone speciation because they no longer mate with each other at high levels.
B)The two populations are in the early stages of reproductive isolation because male flies are more likely to mate with female flies that were raised on the same medium.
C)Fruit flies grown on starch for several generations are no longer capable of consuming maltose.
D)The original population of fruit flies actually consisted of two different species of fruit flies. When hybridization occurred between the two populations, only sterile offspring were produced.

Question 23

Bacteria reproduce asexually so scientists classify them based on

A)the morphological species concept.
B)reproductive isolation.
C)the biological species concept.
D)the idea that they are all strains of the same species.

Question 24

A large population of animals is split in two by a physical barrier. Over time, the genetic makeup of the two resulting populations becomes more and more different, until each population becomes a separate species. This is an example of

A)sympatric speciation.
B)allopatric speciation.
C)genetic drift.
D)natural selection.

Question 25

Which of the following is not an example of a prezygotic barrier?

A)Two populations of plants produce flowers at different times of year.
B)The reproductive organ of the male of one species of damselfly is physically unable to deposit sperm in the reproductive receptacle of the female of another species of damselfly.
C)The hybrid produced by the mating of a lion and a tiger is reproductively sterile.
D)One population of frogs lives in the middle of a pond and the other lives exclusively on land.

Question 26

Speciation

A)can result from geographic isolation.
B)is directed.
C)occurs only in ring species.
D)reduces variation.

Question 27

Populations within a species are connected by

A)gene flow.
B)speciation.
C)continental drift.
D)genetic drift.

Question 28

The red-breasted nuthatch and the white-breasted nuthatch are similar in appearance and, in many regions of the United States, their ranges overlap. The two organisms do not interbreed. Based on this information, red-breasted and white-breasted nuthatches are

A)different species.
B)different populations of the same species.
C)hybrids.
D)polyploids.

Question 29

Which of the following is an example of reproductive isolation?

A)Male deer with large branching antlers are more likely to mate.
B)A blue lizard washes away from a population of mostly green lizards during a hurricane and ends up on an island containing no other lizards to mate with.
C)One population of frogs mates in the deep water of a pond and another population of frogs mates on the shore of the same pond.
D)One individual from a population of fruit flies from an apple orchard is blown by heavy winds into another orchard where it mates with a different population of fruit flies.

Question 30

Two species live in the same area but breed in different parts of their habitat. These species are

A)geographically isolated.
B)ecologically isolated.
C)artificially isolated.
D)likely to produce hybrids.

Question 31

Geographic isolation limits the _____ between populations of a species.

A)genetic differences
B)adaptation
C)directional selection
D)gene flow

Question 32

Using reproductive isolation as a method of defining a species is not useful for

A)species whose ranges overlap.
B)species that cannot produce hybrids.
C)organisms known only from fossils.
D)organisms that reproduce sexually.

Question 33

Which of the following is an example of a prezygotic barrier that can isolate two species living in the same geographic area?

A)The members of two populations of birds living in neighboring forests freely interbreed.
B)One species of cichlid has the same mating behavior as another cichlid species in the same lake.
C)The gametes of one species of orchid in a rainforest are unable to fuse with the gametes of another species of orchid in the same rainforest.
D)Two species of wildflowers mate and produce a hybrid that is capable of successfully breeding with either species.

Question 34

For two populations to accumulate enough genetic differences to cause speciation, the factors that promote these differences

A)must operate in populations that are not physically separated.
B)must have a greater effect than does the amount of ongoing gene flow.
C)need to be combined with the forces of genetic drift.
D)should include polyploidy.

Question 35

The fossils of two adult birds are found in a nest containing several fossilized eggs. Physically, the bird fossils look very different. What are scientists most likely to use to classify these species?

A)the biological species concept
B)the DNA-based species concept
C)the morphological species concept
D)the evidence of reproduction concept

Question 36

The primary difference between the prezygotic barriers and postzygotic barriers involved in reproductive isolation is that prezygotic barriers

A)are related to gametes and postzygotic barriers are related to gametes and to behaviors after birth.
B)occur in species that undergo only asexual reproduction, whereas postzygotic barriers occur in species that undergo sexual reproduction.
C)occur in species undergoing allopatric speciation, whereas postzygotic barriers occur in species undergoing sympatric speciation.
D)prevent fertilization from occurring, whereas postzygotic barriers prevent offspring from developing or being reproductively successful.

Question 37

Why have the two plant populations depicted in the diagram below become so different in the time they were separated by the ocean?

A)Founder's effect; a small group of individuals carrying only the tall allele established a new population on the right side of the ocean.
B)The amount of gene flow between the two populations increased when the ocean separated the plants, so mutations moved from one population to another.
C)When sea levels rose, it killed all of the plants on the right side of the figure. A new species evolved from another plant species already existing in the mountains on the right.
D)The separated populations adapted to the different environments on each side of the ocean and became reproductively isolated.

Question 38

Individuals of the same species generally

A)experience prezygotic barriers to reproduction.
B)do not interbreed extensively.
C)share many common physical and behavioral characteristics.
D)vary only very slightly in appearance.

Question 39

Which of the following is an example of a postzygotic barrier?

A)The gametes cannot join.
B)The zygote fails to develop.
C)The breeding seasons are different.
D)The courtship behaviors are different.

Question 40

Great controversy exists regarding the "hobbits" of Flores Island. Which of the following arguments would not support the hypothesis that hobbits are the same species as modern humans?

A)The different structure of the wrist bones found on Flores Island is an example of the level of nature variation exhibited by Homo sapiens.
B)Reconstructions of the hobbit brain show that it has unique structural features not seen in the brains of modern humans.
C)Modern populations of human pygmies of approximately the same size as the Flores hobbits exist on islands in the Philippines.
D)The island of Flores has never been isolated from other human populations by enough distance to prevent gene flow.

Question 41

____________________ barriers cause speciation to occur by preventing fertilization when two individuals of different populations attempt to mate.

Question 42

An ecological ____________________ can limit a population's ability to adapt to its environment, as the organisms must compromise between what is possible developmentally and what is possible genetically.

Question 43

The offspring of two individuals of different species that interbreed are known as ____________________.

Question 44

A ____________________ species may exist when an organism's range loops around a geographic barrier. Neighboring populations in the range mate, but populations on opposite sides of the barrier cannot mate.

Question 45

The formation of a new species

A)can occur slowly or rapidly.
B)takes at least 1 million years.
C)is evolutionarily insignificant.
D)never happens.

Question 46

In the example below, two new species are created as a result of ____________________ speciation.

Question 47

A rainforest is a highly complex habitat, with organisms living at various levels in the trees, on the ground, and underground. Is it possible to consider two populations living in the same tree to be geographically isolated?

A)No, because if they are in the same tree, they are in the same geographic area.
B)No, because if they are in the same square acre, they cannot be considered geographically isolated.
C)Yes, because they can still undergo sympatric speciation.
D)Yes, because there are so many habitats in one tree that the populations may never interact.

Question 48

In general, geographical isolation occurs when

A)populations migrate to new environments.
B)gene flow is reduced by more than 75 percent due to climate change.
C)mutations overcome genetic drift across physical barriers.
D)populations are separated by a distance that is great enough to limit gene flow.

Question 49

Sympatric speciation

A)occurs only in plants.
B)is impossible, because the populations of a species must be isolated from one another for speciation to occur.
C)is always a result of polyploidy.
D)occurs when a new species emerges from a population in the absence of a geographical barrier.

Question 50

Speciation can occur when populations of a species are separated by a physical barrier becoming ____________________ isolated and subsequently reproductively isolated from one another.

Question 51

Polyploidy in plants can lead to

A)prezygotic isolation.
B)reduced chromosome numbers.
C)reversed meiosis.
D)postzygotic isolation.

Question 52

Polyploidy can lead to very rapid speciation in plants because

A)polyploidy increases the amount of gene flow between polyploid plants and nonpolyploid plants.
B)the DNA sequences of essential genes are altered to such a degree that the polyploid plant can no longer mate with the original species.
C)the gametes of polyploid plants have too many chromosomes and cannot fuse to the gametes of the original species.
D)when a plant becomes polyploid, it often loses the ability to make gametes of any type.

Question 53

The death of zygotes produced by the mating of individuals of two different populations is an example of how ____________________ barriers can lead to reproductive isolation.

Question 54

A biological species is a group of interbreeding populations that is ____________________ isolated from other species of organisms living in the same region.

Question 55

Which of the following does not provide an example of geographic isolation?

A)Two populations live in two valleys on opposite sides of a mountain range.
B)Two populations live on different mountains with a valley between them.
C)Two populations live on opposite sides of a river.
D)Two populations live in different parts of a small lake.

Question 56

The two squirrel species shown in the figure below arose from the same ancestor. The Kaibab squirrel lives on the north rim of the Grand Canyon and Albert's squirrel lives on the south rim. Which is the most likely explanation for their speciation?

A)The population of ancestral squirrel occupied only one of the rims of the Grand Canyon. As the population grew, some members of the population crossed the Grand Canyon to form a new population. The populations had different phenotypes due to the founder effect.
B)The population of the ancestral squirrel was split by the formation of the Grand Canyon. Since the habitats were different on each rim, the populations evolved differently and became reproductively isolated.
C)When the Grand Canyon formed, competition for food and shelter became fierce. The two species arose through sympatric speciation as some individuals gathered food on the north rim rather than the south rim.
D)The ancestral squirrel was actually a hybrid of two squirrel species. When the populations were separated and could no longer mate, the characteristics of the two species became more obvious.

Question 57

Polyploidy can lead to

A)a high rate of gene flow between populations.
B)geographic isolation.
C)fewer chromosomes.
D)reproductive isolation.

Question 58

Two species live near each other but do not respond to each other's courtship displays. This is an example of ____________________ isolation, a type of prezygotic barrier.

Question 59

The only modern humans that exhibit Neandertal genes are descended from non-African ancestors. This is because

A)hybrids produced by interbreeding between Neandertals and African humans were not fertile.
B)the ancestors of African humans have the same ancestors as Neandertals.
C)Neandertals evolved outside of Africa, so only humans who lived outside of Africa could have interbred with them.
D)African humans evolved after Neandertals went extinct.

Question 60

The great diversity of life on Earth is caused by ____________________-the formation of new species.

Question 61

Geographic isolation can result in speciation but usually only over long periods of time.

Question 62

Sympatric speciation always follows allopatric speciation.

Question 63

Ninety-nine percent of all the species that ever existed on Earth are now extinct.

Question 64

Even though humans are causing the extinction of large numbers of species, the process of speciation should replace them within a few decades.

Question 65

The observation that the flowers of this orchid resemble female wasps is an example of a complex adaptation.

Question 66

Gene flow prevents two populations from becoming genetically different.

Question 67

The experiment diagrammed in the image below could lead to the reproductive isolation of fruit fly populations.

Question 68

Evidence suggests that Neandertals and humans are the same species.

Question 69

It takes at least 25 generations of reproduction before a new species can be formed.

Question 70

Sympatric speciation can occur in the absence of geographic isolation.

Question 71

An organism is polyploid if it has more than two complete sets of ____________________.

Question 72

Mutations in developmental genes may provide an advantage at some stages of life, but be fatal at other stages of life.

Question 73

____________________ speciation occurs when a new species arises in the absence of geographic isolation.

Question 74

Some species, like the gray oak and the Gambel oak, hybridize to create fertile offspring, but remain phenotypically distinct as shown by the leaves in the image below. As a result, they are considered different species.

Question 75

When speciation is caused by a rapid change in chromosomal number such as ____________________, new species form in a single generation.

Question 76

Adaptations result from natural selection.

Question 77

The fact that Neandertal genes were found in the modern human genome suggests that these two species interbred at some point creating human-Neandertal ____________________.

Question 78

Speciation as a result of geographic isolation generally occurs at a ____________________ rate than speciation as a result of polyploidy.

Question 79

Sympatric speciation requires geographic isolation of populations.

Question 80

Speciation cannot occur without geographic isolation.