Bio II ch 24 quiz

You want to study divergence of populations, and you need to maximize the rate of divergence to see results within the period of your grant funding. You will form a new population by taking some individuals from a source population and isolating them so the two populations cannot interbreed. What combination of characteristics would maximize your chance of seeing divergence in this study? 1. Choose a random sample of individuals to form the new population. 2. Choose individuals from one extreme to form the new population. 3. Choose a species to study that produces many offspring. 4. Choose a species to study that produces a few, large offspring. 5. Place the new population in the same type of environment as the source population. 6. Place the new population in a novel environment compared to that of the source population. a. 1, 3, and 6 b. 2, 3, and 5 c. 2, 3, and 6 d. 1, 4, and 6

2, 3, and 6

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. 56 b. 14 c. 28 d. 16

28

Use the following description to answer the question. In the oceans 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. In the 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 (1-5), with 1 being the shallowest. Depths from 0 to 100 feet. From the surface, habitats range downward, A1 to A5 on the left (Pacific) side; B1 to B5 on the right (Atlantic) side. Zones except the lowest are equal size; lowest ranges from about 75 feet to the ocean floor. Which of these habitats is likely to harbor the most recently diverged species? a. B4 b. A5 c. A3 d. A1

A1

Use the following description to answer the question. In the oceans 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. In the 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 (1-5), with 1 being the shallowest. 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. 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. d. 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.

They have been geographically isolated from each other for a longer time

How are two different species most likely to evolve from one ancestral species? a. allopatrically, due to extensive inbreeding b. allopatrically, after the ancestral species has split into two populations c. sympatrically, by a point mutation affecting morphology or behavior d. sympatrically, due to extensive inbreeding

allopatrically, after the ancestral species has split into two populations

A hybrid zone is properly defined as ________. a. a zone where sterile hybrids form, kept separate by postzygotic barriers b. an area where members of two closely related species intermingle, but gene flow is prevented by prezygotic barriers c. an area where the ranges of two closely related species overlap but do not interbreed d. an area where mating occurs between members of two closely related species, producing viable offspring

an area where mating occurs between members of two closely related species, producing viable offspring

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 describing species relationship between modern humans and Neanderthals is most applicable in these observations? a. morphological b. ecological c. biological d. genetic

biological

Speciation ________. a. occurs only by the accumulation of small genetic changes over vast expanses of time b. must begin with the geographic isolation of a small, frontier population c. can involve changes to a single gene d. occurs at such a slow pace that no one has ever observed the emergence of new species

can involve changes to a single gene

Use the following description to answer the question. 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 two hundred 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. 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 a now-extinct, non-African fruit

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

Macroevolution is ________. a. defined as the evolution of microscopic organisms into organisms that can be seen with the naked eye You Answered b. defined as a change in allele or gene frequency over the course of many generations c. the same as microevolution, but includes the origin of new species d. evolution above the species level

evolution above the species level

Other than predation by introduced Nile perch, the most likely explanation for the recent decline in cichlid species diversity in Lake Victoria is ________. a. stability b. fusion c. reinforcement d. polyploidy

fusion

What does the biological species concept use as the primary criterion for determining species boundaries? a. gene flow b. morphological similarity c. geographic isolation d. niche differences

gene flow

Use the following information to answer the question. About 3 million years ago, the Isthmus of Panama (a narrow strip of land connecting North and South America) formed, dividing marine organisms into Pacific and Caribbean populations. Researchers have examined species of snapping shrimp on both sides of the isthmus. Based on the morphological species concept, there appeared to be seven pairs of species, with one species of each pair in the Pacific and the other in the Caribbean. The different species pairs live at somewhat different depths in the ocean. Using mitochondrial DNA sequences, the researchers estimated phylogenies and found that each of these species pairs, separated by the isthmus, were indeed each other's closest relatives. The researchers investigated mating in the lab and found that many species pairs were not very interested in courting with each other, and any that did mate almost never produced fertile offspring. (Reference: Y. Kondo and A. Kashiwagi. 2004. Experimentally induced autotetraploidy and allotetraploidy in two Japanese pond frogs. Journal of Herpetology 38(3):381-92.) If the isthmus formed gradually rather than suddenly, what pattern of genetic divergence would you expect to find in these species pairs? a. smaller percentage of difference DNA sequence between species that inhabit than between shallow water b. greater percentage of difference in DNA sequence between species that inhabit shallow water than between species that inhabit deep water c. similar percentages of difference in DNA sequence between all pairs of sister species d. greater percentage of difference in DNA sequence between species that inhabit deep water than between species that inhabit shallow water

greater percentage of difference in DNA sequence between species that inhabit deep water than between species that inhabit shallow water

Use the following description to answer the question. 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 two hundred 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. habitat differentiation b. allopolyploidy c. autopolyploidy d. sexual selection

habitat differentiation

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. behavioral isolation b. habitat isolation c. temporal isolation d. gametic isolation

habitat isolation

Use the following information to answer the question. Two populations of birds with somewhat different coloration live on opposite sides of a peninsula. The habitat between the populations is not suitable for these birds. When birds from the two populations are brought together, they produce young whose appearance is intermediate between the two parents. These offspring will breed with each other or with birds from either parent population, and all offspring of these pairings appear intermediate to various degrees. What keeps the two populations separate? a. temporal reproductive isolation b. habitat isolation c. behavior isolates reproductive activities d. lack of hybrid viability

habitat isolation

Which post zygotic barriers prevent formation of hybrids beyond the first generations? a. increased hybrid fertility b. hybrid breakdown c. hybrid gamete isolation d. increased hybrid vulnerability

hybrid breakdown

Reinforcement is most likely to occur when ________. a. the environment is changing b. gene flow is low c. prezygotic isolating mechanisms are in place d. hybrids have lower fitness than either parent population

hybrids have lower fitness than either parent population

Which statement describes unity within a species? a. The DNA sequence lacks similarities. b. A species is described in terms of its interaction with living and non-living environment. Correct Answer c. Members have the potential to interbreed in nature and produce viable, fertile offspring d. A species can be distinguished by body shape and other structural features.

members have the potential to interbreed in nature and produce viable, fertile offspring

How can reproductive barriers form sympatric populations while their members remain in the same geographic area? a. habitat sharing b. decreased sexual selection c. polyploidy d. increased gene flow

polyploidy

Most causes of speciation are relatively slow in that they may take many generations to see changes, with the exception of ________. a. natural selection b. reinforcement c. polyploidy d. colonization

polyploidy

Two species of frogs belonging to the same genus occasionally mate, but the embryos stop developing after a day and then die. These two frog species separate by ________. a. gametic isolation b. reduced hybrid viability c. reduced hybrid fertility d. hybrid breakdown

reduced hybrid viability

According to the concept of punctuated equilibrium, the "sudden" appearance of a new species in the fossil record means that ________. a. the species will consequently have a relatively short existence compared with other species b. the species is now extinct c. speciation occurred in one generation d. speciation occurred rapidly in geologic time

speciation occurred rapidly in geologic time

How do hybrid zones slow reproductive isolation? a. increased gene flow b. decreased embryonic mortality c. morphologic abnormalities d. species with incomplete mating barriers

species with incomplete mating barriers

In a hypothetical situation, a certain species of flea feeds only on pronghorn antelopes. In the western United States, pronghorns and cattle often associate with one another in the same open rangeland. Some of these fleas develop a strong preference for cattle blood and mate only with other fleas that prefer cattle blood. The host mammal can be considered as the fleas' habitat. If this situation persists, and new species evolve, this would be an example of ________. a. allopatric speciation and habitat isolation b. sympatric speciation and temporal isolation c. allopatric speciation and gametic isolation d. sympatric speciation and habitat isolation

sympatric speciation and habitat isolation

Among known plant species, which of these have been the two most commonly occurring phenomena that have led to the origin of new species? a. sympatric speciation and sexual selection b. allopatric speciation and sexual selection c. allopatric speciation and polyploidy d. sympatric speciation and polyploidy

sympatric speciation and polyploidy

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. Assuming events like this are very rare, which of the following scenarios is least likely? a. The frequency of hybrid offspring would decrease. b. Pied females would rarely mate with collared males. c. Migrant pied males would produce fewer offspring than would resident pied males. d. Migrant males would mate with collared females more often than with pied females.

the frequency of hybrid offspring would decrease

Use the following description to answer the question. In the oceans 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. In the 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 (1-5), with 1 being the shallowest. Depths from 0 to 100 feet. From the surface, habitats range downward, A1 to A5 on the left (Pacific) side; B1 to B5 on the right (Atlantic) side. Zones except the lowest are equal size; lowest ranges from about 75 feet to the ocean floor. Which factor is most important for explaining why there are equal numbers of snapping shrimp species on either side of the isthmus? a. the depth of the sea b. the elevation of the isthmus above sea level c. the relative shortness of time they have been separated d. the number of actual depth habitats between the surface and the sea floor

the relative shortness of time they have been separated

Many songbirds breed in North America in the spring and summer, and then migrate to Central and South America in the fall. They spend the winter in these warmer areas where they feed and prepare for the spring migration north and another breeding season. Two hypothetical species of sparrow, A and B, overwinter together in mixed flocks in Costa Rica. In spring, species A goes to the east coast of North America, and species B goes to the west coast. What can you say about the isolating mechanisms of these two species? a. Reinforcement must be occurring when they winter together. b. They must have strong postzygotic isolating mechanisms to spend winter in such close proximity. c. These two species mate in different climates. d. They must have strong prezygotic isolating mechanisms to spend winter in such close proximity.

these two species mate in different climates

Which of the following statements describes mechanical isolation prezygotic barrier? a. two snails have shells that spiral in different directions b. two species mate at different times c. two species share courtship activities d. two species live in different habitats

two species live in different habitats