Question 1

Which of the following best points to a close evolutionary relationship between two different species?

Accepted Answer

Similar DNA indicates a close evolutionary relationship between two species more than any of the other options. While similar appearance, diet, habitat, and mating rituals can also suggest a close relationship, these traits can also be the result of convergent evolution or other factors. However, DNA is a direct reflection of the genetic material passed down from a common ancestor, providing stronger evidence for a close evolutionary relationship between two species.

Question 2

A male from species A mates with a female from species B.Male A's sperm swims and finds the egg,but the sperm is unable to penetrate the egg.This is an example of

Accepted Answer

Gametic isolation occurs when gametes from different species are unable to fuse and produce a zygote. In this scenario, male A's sperm is unable to penetrate the egg of female B, indicating that the gametes from the two species are not compatible.

Question 3

Two populations of frog are separated from each other by a large distance and rarely interbreed with each other.However,approximately one male frog a year makes the journey and breeds with females in the other population.Would you expect these populations to eventually become separate species? Why or why not?

Accepted Answer

The answer of Two populations of frog are separated from...

Question 4

Pollen from a tomato plant lands on a grapefruit flower.The pollen fails to grow a pollen tube.This is an example of

Accepted Answer

This is an example of gametic isolation, where the pollen from the tomato plant fails to grow a pollen tube in the grapefruit flower, preventing fertilization. Temporal isolation refers to differences in mating seasons, but there is no mention of this in the scenario. Behavioral isolation refers to differences in mating behaviors, ecological isolation refers to differences in habitat, and hybrid infertility refers to hybrid offspring being infertile, which do not apply to this scenario.

Question 5

Two species of salamanders have overlapping territories and they successfully mate and produce eggs.However,most of the eggs fail to hatch.Only 10% of them hatch,but the tadpoles are weak and are almost all killed by predators.The few tadpoles that exit the water have weak bones and soon die.This is an example of

Accepted Answer

The fact that the eggs have low hatching success and the resulting tadpoles have weak bones and high mortality rates indicates that there is some kind of genetic incompatibility between the two species, leading to hybrid inviability.

Question 6

Why is mitochondrial DNA slower to change than nuclear DNA?

Accepted Answer

The answer of Why is mitochondrial DNA slower to change...

Question 7

Spotted skunks and striped skunks have overlapping habitat ranges,but no hybrid offspring are produced.Spotted skunks breed in the fall,striped skunks breed in the spring.This is an example of

Accepted Answer

The fact that spotted skunks breed in the fall and striped skunks breed in the spring creates temporal isolation, which means that they are reproductively isolated due to differences in the timing of their mating seasons. This prevents them from producing hybrid offspring, despite overlapping habitat ranges. Gametic isolation refers to the inability of sperm from one species to fertilize eggs of another species, which is not applicable in this case. Behavioral isolation involves differences in courtship behaviors or other mating rituals, which is not mentioned in the scenario. Ecological isolation refers to species occupying different habitats, which is also not applicable here. Hybrid infertility refers to the inability of hybrid offspring to produce viable offspring, which is not mentioned in the scenario.

Question 8

Why doesn't the egg cell receive the mitochondria found in a sperm cell?

Accepted Answer

The answer of Why doesn't the egg cell receive the...

Question 9

List at least five ways that two species may be reproductively isolated from each other.

Accepted Answer

The answer of List at least five ways that two...

Question 10

Snail species A has a shell that spirals counterclockwise,but a mutation has caused some individuals to have a clockwise shell.The genitalia of the two versions are incompatible,leading some scientists to say that the clockwise snails are reproductively isolated.Could the clockwise snails become a new species?

Accepted Answer

The answer of Snail species A has a shell that...

Question 11

Which of the following can influence the evolution of a species?

Accepted Answer

All of the given options can influence the evolution of a species. Mutation can introduce new genetic variation, natural selection can act on this variation to affect the survival and reproduction of individuals, genetic drift can cause random changes in the frequency of genes within a population, and gene flow can introduce new genetic material from other populations. All of these processes can lead to evolutionary change over time.

Question 12

Snail species A has a shell that spirals counterclockwise,but a mutation has caused some individuals to have a clockwise shell.The genitalia of the two versions are incompatible,leading some scientists to say that the clockwise snails are reproductively isolated.This is an example of

Accepted Answer

This is an example of mechanical isolation because the physical incompatibility of the genitalia between the two versions of snail species A prevents them from successfully mating and reproducing. Mechanical isolation is a form of reproductive isolation where differences in the size and shape of reproductive organs prevent the mating between two species or variations.

Question 13

Would you expect members of the same family,same genus,or same species to share the most characteristics with one another? Explain.

Accepted Answer

The answer of Would you expect members of the same...

Question 14

Some reproductive barriers prevent the formation of a zygote,others allow offspring to be born.Discuss the barriers that allow the birth of offspring,and explain why these hybrids are not the beginning of a pathway to a new species being formed.

Accepted Answer

The answer of Some reproductive barriers prevent the formation of...

Question 15

What are the four main forces of evolution that act upon a species' gene pool?

Accepted Answer

The answer of What are the four main forces of...

Question 16

Is reproductive isolation among populations of the same species always detrimental to their survival? If yes,explain why.If no,give one example when reproductive isolation is a problem and one example when it is not.

Accepted Answer

The answer of Is reproductive isolation among populations of the...

Question 17

Kangaroo rats,kangaroo mice,and pocket mice are found only in the deserts of the Southwestern United States.They share a number of features,including external,fur-lined cheek pouches,which they use to gather and transport seeds to their burrows.But they are also quite different from one another in size,overall shape,behavior,and other features.The best explanation for their similarities and differences is that

Accepted Answer

The presence of external, fur-lined cheek pouches among these species suggests that they share a common ancestor. The differences in other features are likely adaptations to specific environments through natural selection.

Question 18

An ethnobiological study of several Mexican Amerindian groups looked at how they named the plants in their region.Biologists noted that their plant names and groupings closely matched the species and generic groupings used by botanists.For example,each species of prickly pear cactus (Opuntia)was clearly defined,and all species of Opuntia were placed into one category in the local language.Other studies have shown that other traditional groups have similar native taxonomy systems that match well with biologists' grouping to the generic level.Why is this not surprising from a taxonomic and an evolutionary perspective?

Accepted Answer

The answer of An ethnobiological study of several Mexican Amerindian...

Question 19

In North America,there are more than 60 species of mice in the genus Peromyscus,most of whom closely resemble one another.You wish to determine the relatedness of three of these species: the deer mouse,the oldfield mouse,and the white-footed mouse.You set up breeding experiments and find that deer mice and oldfield mice will reluctantly breed with one another,but neither one will breed with white-footed mice.What do you determine to be the pattern of relatedness of these three species?

Accepted Answer

The answer of In North America,there are more than 60...

Question 20

During the building of the London subway system in the late 1800s,a species of aboveground-dwelling mosquito expanded its distribution to include the underground tunnels,where it successfully lived and bred.In the late 1990s,scientists comparing the two groups of mosquitoes discovered that they are now different species.The most likely mode of reproductive isolation for these two species is

Accepted Answer

Ecological isolation is the most likely mode of reproductive isolation in this scenario because the two groups of mosquitoes are living in different environments (aboveground and underground), which prevents them from interbreeding.

Quiz 15: A: Nonadaptive Evolution and Speciation Urban Evolution