Julianne Zedalis; John Eggebrecht

38 .

Define and describe community ecology. Give an example.

It is the study of the number of individuals of one species in an area as well as how and why the number changes over time. An example would be counting the number of individuals of the Karner blue butterfly, a federally endangered species whose population density is highly influenced by the abundance of wild lupine.
It is the study of the processes and consequences of interactions within and among different species within an area. An example would be the work of scientists who work in a marsh studying the various interactions of several populations of birds, crabs, and grasses without studying the water or air quality.
It is the study of the physiological, morphological, and behavioral adaptations that enable individuals to live in specific habitats. An example would be the work of scientists who work in a marsh studying the various interactions of several populations of birds, crabs, and grasses without studying the water or air quality.
It is the study of the processes and consequences of interactions within and among different species within an area. An example would be counting the number of individuals of the Karner blue butterfly, a federally endangered species whose population density is highly influenced by the abundance of wild lupine.

39 .

(credit: modification of work by John A. Vucetich/The Wolves and Moose of Isle Royale)

The graph shows the wolf and moose populations in Isle Royale, a protected national park in Michigan. Wolves are the main predator of moose, but there are many other factors at play.

Around 1984, the moose population suddenly crashed.

Make a hypothesis explaining why the wolf population did not increase during this time.

The moose population dropped due to a very severe winter.
The moose population dropped due to over hunting by the wolves.
The moose population dropped due to a disease slowly spreading through the population.
The moose population dropped due their habitat being destroyed by people.

40 .

(credit: modification of work by John A. Vucetich/The Wolves and Moose of Isle Royale)

The graph shows the wolf and moose populations in Isle Royale, a protected national park in Michigan. Wolves are the main predator of moose, but there are many other factors at play.

Some time during the time frame covered by this graph, humans accidentaly introduced canine parvovirus, a wolf disease to the wolf population.

When did this event most likely occur?

Between 1969 and 1974.
Between 1974 and 1979.
Between 1979 and 1984.
Between 1984 and 1989.

41 .

Refer to Figure 35.2

.

(credit: modification of work by Ali Swanson/Snapshot Serengeti)

The graph shows lion, cheetah and wild dog populations in the Serengeti, a geographical area in Africa. These predators often hunt the same prey and are in competition with each other.

Lions kill cheetah cubs when they can find them. Make a claim about how this effects cheetah populations based on the graph.

Killing the cheetah cubs caused cheetah population to go into a gradual decline.
Killing the cheetah cubs caused cheetah population to go into a steep decline.
Killing the cheetah cubs caused the cheetah to become locally extinct in the area.
Killing the cheetah cubs had no effect on the cheetah population.

42 .

(credit: modification of work by Bermuda Biological Station for Research, Florida International University)

The graphs show the temperature of the Caribbean Sea throughout 1995 at various depths.

Make a claim based on these graphs.

Surface temperatures vary very little during the year.
Temperature below 200 m varies very little during the year.
Surface temperature becomes colder than temperatures at 400 m depth during winter months.
Temperatures tend to increase with increasing depth between 200 m and 400 m.

43 .

The American white pelican migrates from North America to Central America in the winter months. Give three reasons why these birds follow an annual migration pattern.

The American white pelican follows an annual migration pattern in search of suitable mates, warmer climates, and suitable habitat. Warmer climates help them in maintaining a constant body temperature.
The American white pelican follows an annual migration pattern in search of food, salt water, and cooler climates. Cooler climates help these birds in reproduction.
The American white pelican follows an annual migration pattern in search of food, warmer climates, and suitable habitat. Warmer climates help them in maintaining a constant body temperature.
The American white pelican follows an annual migration pattern in search of warmer climates only. Warmer climates help them in maintaining a constant body temperature.

44 .

(credit: modification of work by Peter Chen/College of DuPage)

The graph shows the net primary productivity of different ecosystems.

Open oceans are poor in nutrients but account for the largest amount of net primary production on Earth. How is this possible?

Open oceans are not poor in nutrients.
Most of the Earth is covered by open oceans.
Open oceans include other types of ecosystems, like estuaries and coral reefs.
Open oceans do not account for most of the net primary production on Earth.

45 .

(credit: modification of work by Peter Chen/College of DuPage)

The graph shows the net primary productivity of different ecosystems.

Which terrestrial ecosystem has the lowest amount of nutrients?

Extreme desert, rock, sand, ice.
Desert and semidesert scrub.
Savanna.
Tundra.

46 .

What are endemic species? Give an example and explain how endemic species differ from generalist species.

Endemic species are found naturally in specific geographic areas that are usually restricted in size. For example, the raccoon is found only in Australia. Generalist species are found in a wide range of geographical locations. For example, the koala is native to most of North and Central America.
Endemic species are those which are likely to be extinct. For example, the koala (a marsupial) is found only in Australia. Generalist species are found in a wide range of geographical locations. For example, the raccoon is native to most of North and Central America.
Endemic species are found in a wide range of geographical locations. For example, the koala (a marsupial) is found only in Australia. Generalist species are found naturally in specific geographic areas that are usually restricted in size. For example, the raccoon is native to most of North and Central America.
Endemic species are found naturally in specific geographic areas that are usually restricted in size. For example, the koala (a marsupial) is found only in Australia. Generalist species are found in a wide range of geographical locations. For example, the raccoon is native to most of North and Central America.

47 .

Deserts and subtropical deserts experience low precipitation and extremes in temperature. For a plant to survive and reproduce, what adaptations should it have? Why?

To survive, they need prop roots, reduced foliage and fleshy leaves with sunken stomata to reduce transpiration. Also, they should have seeds that can remain dormant over long periods.
To survive, they need deep roots, reduced foliage and fleshy leaves with sunken stomata to reduce transpiration. Also, they should have seeds that can remain dormant over long periods.
To survive, they need deep roots, reduced foliage and fleshy leaves with sunken stomata to reduce transpiration. Also, these plants need to grow in clumps.
To survive, they need deep roots, increased foliage, and fleshy leaves with sunken stomata to reduce transpiration. Also, the plants need seeds that can remain dormant over long periods.

48 .

In what ways are the subtropical desert and the arctic tundra similar?

Both are characterized by animals, which are adapted to burrowing.
Both are characterized by plants, which prefer to grow in clumps.
Both are characterized by low water availability and, as a result, low net primary productivity.
Both are characterized by plants, which are mostly perennials.

49 .

Describe the chaparral biome. How does it does it differ from subtropical deserts?

Shrubs dominate chaparral vegetation and are well adapted to the periodic fires in the area. Ashes left behind after fires are rich in nutrients, which promote regrowth. Subtropical deserts are characterized by their high precipitation and water-retaining plants.
Shrubs dominate chaparral vegetation and are well adapted to the periodic fires in the area. Ashes left behind after fires are rich in nutrients, which promote regrowth. Subtropical deserts are characterized by their low precipitation and water-retaining plants.
Lichens dominate chaparral vegetation and are well adapted to the periodic fires in the area. Ashes left behind after fires are rich in nutrients, which promote regrowth. Subtropical deserts are characterized by their low precipitation and water-retaining plants.
Shrubs dominate chaparral vegetation but are not well adapted to the periodic fires in the area. Ashes left behind after fires are rich in nutrients, which promote regrowth. Subtropical deserts are characterized by their low precipitation and water-retaining plants.

50 .

What happens to aquatic life in deep lakes when water freezes during the winter months?

During winters, layer of ice falls on water surface as it is less dense than water. Water is densest at 7° C and retains its liquid form below the water surface. The aquatic life can exist in liquid water.
During winters, the aquatic life exists in liquid water, which is present below the surface layer, by consuming more resources so they can survive during the harsh winter season.
During winters, a layer of ice forms on the water surface, as ice is less dense than water. Water is densest at 4°C and retains its liquid form below the water surface, where the ice layer is. In liquid water, the aquatic life can survive using the resources available.
During winters, ice forms only on the surface and a few meters below the surface of water. Water is densest at 4°C and retains its liquid form below the water surface, where the ice layer is. In liquid water, the aquatic life can exist using the resources available.

51 .

Explain the challenges facing organisms living in the intertidal zone and their adaptations to meet these challenges.

They are subject to constant exposure to air, sunlight, periods of dryness, and pounding waves. For this reason, some species have an exoskeleton.
They are subject to periodic exposures to air, sunlight, periods of dryness, and pounding waves. For this reason, some species have an exoskeleton.
They are subject to periodic exposures to air, sunlight, periods of dryness, and pounding waves. For this reason, all species have an exoskeleton.
They are subject to periodic exposures to air, sunlight, periods of dryness, and pounding waves. For this reason, most species have an endoskeleton.

52 .

If algae grows out of proportion as seen during algal blooms, how does it affect the ecosystem?

Photosynthetic organisms will not be able to grow. The animals and birds that live on those organisms will be affected. As the algae die, oxygen will be depleted, affecting fish and other aquatic animals. The pH of water will change, affecting metabolic processes as well.
Non-photosynthetic organisms will not be able to grow due to lack of light. The photosynthetic organisms that require them to live will be affected. As the algae die, oxygen will be depleted, affecting fish and other aquatic animals. The pH of water will change, affecting metabolic processes as well.
Photosynthetic organisms will not be able to grow. The animals and birds that live on those organisms will be affected. As the algae die, carbon dioxide will be depleted, affecting fish and other aquatic animals. The pH of water will change, affecting metabolic processes as well.
Non-photosynthetic organisms will not be able to grow. The animals and birds that live on those organisms will be affected. As the algae die, carbon dioxide will be depleted, affecting fish and other aquatic animals. The pH of water will change, affecting metabolic processes as well.

53 .

What are some abiotic factors that affect freshwater biomes? Explain.

Salinity and sunlight are both abiotic factors that influence life in freshwater biomes. As organisms living in freshwater biomes require high salt density for survival, its depletion would kill the organisms. Many organisms that serve as food for others are photosynthetic and would die if algae blooms obscured the light. Their decomposition as well as the depletion of oxygen by algae would cause organisms that require oxygen to die out as well.
Salinity and sunlight are both abiotic factors that influence life in freshwater biomes. As organisms living in freshwater biomes cannot tolerate high salt levels, these organisms would not survive if it increased. Many organisms that serve as food for others are photosynthetic would die if algal blooms obscured the light. Their decomposition and the depletion of carbon dioxide by algae would cause organisms that require carbon dioxide to die out as well.
Salinity and sunlight are both abiotic factors that influence life in freshwater biomes. As organisms living in freshwater biomes cannot tolerate high salt levels, these organisms would not survive if it were to increase significantly. Many organisms that serve as food for others are photosynthetic and would die if algal blooms obscure light. Their decomposition and depletion of oxygen by algae would cause organisms that require oxygen to die out as well.
Salinity and temperature are both abiotic factors that influence life in freshwater biomes. As organisms living in freshwater biomes cannot tolerate high salt concentrations, those organisms would not survive if salt concentrations increased significantly. Many organisms that serve as food for others are photosynthetic and would die if algal blooms obscured the light. Their decomposition and the depletion of oxygen by algae would cause organisms that require oxygen to die out as well.

54 .

Is it possible to reverse the effects of global warming? What measures may help in reducing global climate change?

It is possible to reverse the effects of global warming by reducing the usage of fossil fuels, using alternative fuels, using alternatives to CFC’s and using natural sources of energy.
It is not possible to reverse the effects of global warming, as major climate changes have already been occurred and settled in the environment. Reducing fossil fuel usage, using natural sources of energy and alternative fuels may slow down global climate change.
It is not possible to reverse the effects of global warming, as we are already witnessing changes in the environment, plants and animal behavior. Reducing fossil fuel usage and using natural sources of energy may slow down global climate change.
It is possible to reverse the effects of global warming by working on new technologies that will help in preventing temperature changes worldwide. Using wind power and high efficiency natural gas generation will help in achieving this goal.

55 .

(credit: modification of work from Global Monitoring Laboratory)

The red line on the graph shows the monthly carbon dioxide measurements between 2016 and 2021. Each dot represents a month. The year's first dot is January.

What is the dependent variable on this graph?

Carbon dioxide levels measured.
Time.
The month.
Carbon dioxide emissions.

56 .

(credit: modification of work from United States Environmental Protection Agency)

This graph shows the US emissions of greenhouse gasses by sector. Note this graph has electricity use distributed to various sectors.

Make a claim based on this graph.

A 20% decrease in greenhouse gas emissions by agricultural activities would reduce the total emissions by about 5%.
A 20% decrease in greenhouse gas emissions by industry would reduce the total emissions by about 6%
A 20% decrease in greenhouse gas emissions by transportation would reduce the total emissions by about 5%
A 20% decrease in greenhouse gas emissions by residential and commercial use would reduce the total emissions by about 8%

57 .

(credit: modification of work from Global Monitoring Laboratory)

The red line on the graph shows the monthly carbon dioxide measurements between 2016 and 2021. Each dot represents a month. The year's first dot is January.

Make a claim based on this data.

Winter months in the Northern hemisphere see more carbon dioxide emissions, possibly due to heating.
Carbon dioxide emissions peak at summer months, possibly due to increased agricultural and industrial activity.
Carbon dioxide emissions are constant throughout the year. Summer's increased agricultural activity is balanced by winter heating in the northern hemisphere.
Carbon dioxide emissions constantly increase during the year, due to increasing population and increased use of fossil fuels.

Critical Thinking Questions