PCB 3043 Chapter 22 || 100% Errorless Answers.
Select the statements that describe the common effects of landscape fragmentation.
-Increasing edge areas alters the species composition of a habitat.
-Reducing the total habitat size causes declines in species diversity.
-Increasing the distance between patches improves species dispersal.
-Reducing the size of each patch increases the total species richness. correct answers -Increasing
edge areas alters the species composition of a habitat.
-Reducing the total habitat size causes declines in species diversity.
Select the statement that describes why the quality of the matrix that exists between habitat
fragments determines the movement of amphibian species between ponds.
-Amphibians need moisture to breathe, so a dry matrix between ponds prevents dispersal.
-Amphibians only travel in water, so the matrix between fragments must contain a stream.
-Amphibians cannot travel far, so the fragments must not be separated by long distances.
-Amphibians reproduce quickly, so the fragments must be large enough for the population.
correct answers -Amphibians need moisture to breathe, so a dry matrix between ponds prevents
dispersal.
Increasing local diversity _________________ the intercept of the species-area relationship.
correct answers Increasing local diversity INCREASES the intercept of the species-area
relationship.
Increasing regional diversity _________________ the intercept of the species-area relationship.
correct answers Increasing regional diversity INCREASES the intercept of the species-area
relationship.
Classify each description as a characteristic of alpha, beta, or gamma diversity:
Counts the number of species in a single habitat type. correct answers Alpha diversity
Classify each description as a characteristic of alpha, beta, or gamma diversity:
Compares two habitats and counts the number of unique species not shared between the two
habitats. correct answers Beta diversity
Classify each description as a characteristic of alpha, beta, or gamma diversity:
Counts the total species diversity in all the habitats in a geographic area. correct answers Gamma
diversity
Why do regions with high species diversity also exhibit high niche diversity?
-Species sorting allows species to partition themselves into local habitats.
, -Areas with high species diversity tend to have homogeneous habitats.
-If alpha diversity is high, then gamma diversity is also high.
-Every species must occupy a unique niche within its community. correct answers -Every species
must occupy a unique niche within its community.
Why do small islands that are distant from a mainland tend to have fewer plant species than large
islands that are close to a mainland?
-Distant islands are colonized more often by non-native plants that outcompete native plants.
-Distant islands are harder to get to and require specialized seed dispersal strategies.
-Small islands may have fewer types of plant habitats than large islands.
-Small islands support smaller plant populations that are more prone to extinction.
-Small islands are more often round-shaped which gives them a higher ratio of edge habitat for
plants. correct answers -Distant islands are harder to get to and require specialized seed dispersal
strategies.
-Small islands may have fewer types of plant habitats than large islands.
-Small islands support smaller plant populations that are more prone to extinction.
Trace the course of the development and dispersal of marsupials in the context of continental
drift. correct answers 1. Marsupials first evolved in what is now South America.
2. A few marsupials migrated across southern Pangaea into what is now Australia.
3. Marsupials diversified on the Gondwanan landmasses that contained present-day South
America and Australia.
4. One type of marsupial crossed the Panama land bridge into what is now North America.
5. Marsupials reached present-day distribution.
In what ways might a region's size and age since initial colonization affect the region's species
richness?
-Species in a small region will have a lower extinction risk than species in a larger region.
-A small region will end up supporting fewer species than a larger region.
-The rate at which new species move into the region will slow down over time.
-The number of species in the region will continuously increase over time. correct answers -A
small region will end up supporting fewer species than a larger region.
-The rate at which new species move into the region will slow down over time.
In what ways does studying thousands of years of climate data and plant distribution data from a
specific area help explain the area's current composition of plant species?
-It demonstrates that the species living in an area change as the climate in the area changes.
-It makes it clear that some species may still be in the process of migrating into or out of the
area.
-It verifies that the number of species remains constant, even if species composition changes.
-It shows that as an area's climate changes, resident species readily adapt to new conditions.
correct answers -It demonstrates that the species living in an area change as the climate in the
area changes.
Select the statements that describe the common effects of landscape fragmentation.
-Increasing edge areas alters the species composition of a habitat.
-Reducing the total habitat size causes declines in species diversity.
-Increasing the distance between patches improves species dispersal.
-Reducing the size of each patch increases the total species richness. correct answers -Increasing
edge areas alters the species composition of a habitat.
-Reducing the total habitat size causes declines in species diversity.
Select the statement that describes why the quality of the matrix that exists between habitat
fragments determines the movement of amphibian species between ponds.
-Amphibians need moisture to breathe, so a dry matrix between ponds prevents dispersal.
-Amphibians only travel in water, so the matrix between fragments must contain a stream.
-Amphibians cannot travel far, so the fragments must not be separated by long distances.
-Amphibians reproduce quickly, so the fragments must be large enough for the population.
correct answers -Amphibians need moisture to breathe, so a dry matrix between ponds prevents
dispersal.
Increasing local diversity _________________ the intercept of the species-area relationship.
correct answers Increasing local diversity INCREASES the intercept of the species-area
relationship.
Increasing regional diversity _________________ the intercept of the species-area relationship.
correct answers Increasing regional diversity INCREASES the intercept of the species-area
relationship.
Classify each description as a characteristic of alpha, beta, or gamma diversity:
Counts the number of species in a single habitat type. correct answers Alpha diversity
Classify each description as a characteristic of alpha, beta, or gamma diversity:
Compares two habitats and counts the number of unique species not shared between the two
habitats. correct answers Beta diversity
Classify each description as a characteristic of alpha, beta, or gamma diversity:
Counts the total species diversity in all the habitats in a geographic area. correct answers Gamma
diversity
Why do regions with high species diversity also exhibit high niche diversity?
-Species sorting allows species to partition themselves into local habitats.
, -Areas with high species diversity tend to have homogeneous habitats.
-If alpha diversity is high, then gamma diversity is also high.
-Every species must occupy a unique niche within its community. correct answers -Every species
must occupy a unique niche within its community.
Why do small islands that are distant from a mainland tend to have fewer plant species than large
islands that are close to a mainland?
-Distant islands are colonized more often by non-native plants that outcompete native plants.
-Distant islands are harder to get to and require specialized seed dispersal strategies.
-Small islands may have fewer types of plant habitats than large islands.
-Small islands support smaller plant populations that are more prone to extinction.
-Small islands are more often round-shaped which gives them a higher ratio of edge habitat for
plants. correct answers -Distant islands are harder to get to and require specialized seed dispersal
strategies.
-Small islands may have fewer types of plant habitats than large islands.
-Small islands support smaller plant populations that are more prone to extinction.
Trace the course of the development and dispersal of marsupials in the context of continental
drift. correct answers 1. Marsupials first evolved in what is now South America.
2. A few marsupials migrated across southern Pangaea into what is now Australia.
3. Marsupials diversified on the Gondwanan landmasses that contained present-day South
America and Australia.
4. One type of marsupial crossed the Panama land bridge into what is now North America.
5. Marsupials reached present-day distribution.
In what ways might a region's size and age since initial colonization affect the region's species
richness?
-Species in a small region will have a lower extinction risk than species in a larger region.
-A small region will end up supporting fewer species than a larger region.
-The rate at which new species move into the region will slow down over time.
-The number of species in the region will continuously increase over time. correct answers -A
small region will end up supporting fewer species than a larger region.
-The rate at which new species move into the region will slow down over time.
In what ways does studying thousands of years of climate data and plant distribution data from a
specific area help explain the area's current composition of plant species?
-It demonstrates that the species living in an area change as the climate in the area changes.
-It makes it clear that some species may still be in the process of migrating into or out of the
area.
-It verifies that the number of species remains constant, even if species composition changes.
-It shows that as an area's climate changes, resident species readily adapt to new conditions.
correct answers -It demonstrates that the species living in an area change as the climate in the
area changes.
