Question 1

What is the single greatest threat to biodiversity?

Accepted Answer

A)  overharvesting of commercially important species
B)  introduced species that compete with native species
C)  pollution of Earth's air, water, and soil
D)  disruption of trophic relationships as more and more prey species become extinct
E)  habitat alteration, fragmentation, and destruction E

Question 2

Relatively small geographic areas with high concentrations of endemic species and a large number of endangered and threatened species are known as

Accepted Answer

A)  endemic sinks.
B)  critical communities.
C)  biodiversity hot spots.
D)  endemic metapopulations.
E)  bottlenecks. C

Question 3

For the following questions, match the statement with the appropriate term/phrase.
-This causes an increase in the intensity of UV radiation reaching Earth.

Accepted Answer

A)  depletion of ozone layer
B)  acid precipitation
C)  biological magnification
D)  greenhouse effect
E)  eutrophication A

Question 4

You are trying to determine if a particular species will become invasive in your province. You know there are common attributes of invasive species; which attribute would be least applicable to invasive species?

Accepted Answer

A)  well-developed dispersal mechanisms
B)  low ecological tolerance
C)  fast maturation
D)  high reproductive output
E)  known to be invasive in many countries

Question 5

Which of the following is a consequence of biological magnification?

Accepted Answer

A)  Toxic chemicals in the environment pose greater risk to top-level predators than to primary consumers.
B)  Populations of top-level predators are generally smaller than populations of primary consumers.
C)  The biomass of producers in an ecosystem is generally higher than the biomass of primary consumers.
D)  Only a small portion of the energy captured by producers is transferred to consumers.
E)  The amount of biomass in the producer level of an ecosystem decreases if the producer turnover time increases.

Question 6

Of the following ecosystem types, which have been impacted the most by humans?

Accepted Answer

A)  wetland and riparian
B)  open and benthic ocean
C)  desert and high alpine
D)  taiga and second-growth forests
E)  tundra and arctic

Question 7

For the following questions, match the statement with the appropriate term/phrase.
-This causes extremely high levels of toxic chemicals in fish-eating birds.

Accepted Answer

A)  depletion of ozone layer
B)  acid precipitation
C)  biological magnification
D)  greenhouse effect
E)  eutrophication

Question 8

Use the graph and information provided in the paragraph below to answer the following questions.
Flycatcher birds that migrate from Africa to Europe feed their nestlings a diet that is almost exclusively moth caterpillars. The graph below shows the mean dates of arrival, bird hatching, and peak caterpillar season for the years 1980 and 2000.
 
-If the nestlings of flycatchers are to benefit from the shift in peak caterpillar season from June 3, 1980 to May 15, 2000, in which direction should the May 25, 2000 peak bird hatching date move?

Accepted Answer

A)  to the left so it corresponds to the mean date of arrival in 2000
B)  to the left so it corresponds with the new peak caterpillar season in 2000
C)  to the right so there is no overlap in the May 15 and May 25 (year 2000) curves
D)  no movement is necessary because the caterpillars grow slowly so the nestlings will have enough food to eat
E)  no movement is necessary because herbicides can be used to kill the vegetation the caterpillars feed on and therefore the peak hatching time of caterpillars will move to the right from May 15 to May 25, 2000

Question 9

The greatest cause of the biodiversity crisis, the one which includes all of the others, is

Accepted Answer

A)  pollution.
B)  global warming.
C)  habitat destruction.
D)  introduced species.
E)  human overpopulation.

Question 10

Which of the following provides the best evidence of a biodiversity crisis?

Accepted Answer

A)  the incursion of a non-native species
B)  increasing pollution levels
C)  decrease in regional productivity
D)  high rate of extinction
E)  climate change

Question 11

Burning fossil fuels releases oxides of sulphur and nitrogen. These air pollutants can be responsible for

Accepted Answer

A)  the death of fish in lakes.
B)  precipitation with a pH as low as 3.0.
C)  calcium deficiency in soils.
D)  direct damage to plants by leaching nutrients from the leaves.
E)  All of the options are correct.

Question 12

Extinction is a natural phenomenon. It is estimated that 99% of all species that ever lived are now extinct. Why then do we say that we are now experiencing an extinction (loss of biodiversity)crisis?

Accepted Answer

A)  Humans are ethically responsible for protecting endangered species.
B)  Scientists have finally identified most of the species on Earth and are thus able to quantify the number of species becoming extinct.
C)  The current rate of extinction is high and human activities threaten biodiversity at all levels.
D)  Humans have greater medical needs than at any other time in history, and many potential medicinal compounds are being lost as plant species become extinct.
E)  Most biodiversity hot spots have been destroyed by recent ecological disasters.

Question 13

Use the graph and information provided in the paragraph below to answer the following questions.
Flycatcher birds that migrate from Africa to Europe feed their nestlings a diet that is almost exclusively moth caterpillars. The graph below shows the mean dates of arrival, bird hatching, and peak caterpillar season for the years 1980 and 2000.
 
-Why were ecologists concerned about the shift in the peak caterpillar season from June 3, 1980, to May 15, 2000?

Accepted Answer

A)  The caterpillars would have eaten much of the foliage of the trees where flycatchers would have nested, rendering their nests more open to predation.
B)  The earlier hatching of caterpillars would compete with other insect larval forms which the flycatchers would also use to feed their young.
C)  The 2000 flycatcher nestlings would miss the peak caterpillar season and might not be as well fed.
D)  The flycatchers would have to migrate sooner to match their brood-rearing to the time of peak caterpillar season.
E)  Pesticides, which have a negative effect on the ecosystem, would have to be used to control the earlier outbreak of caterpillar hatching.

Question 14

Overexploitation encourages extinction and is most likely to affect

Accepted Answer

A)  animals that occupy a broad ecological niche.
B)  large animals with low intrinsic reproductive rates.
C)  most organisms that live in the oceans.
D)  terrestrial organisms more than aquatic organisms.
E)  edge-adapted species.

Question 15

The introduction of the brown tree snake in the 1940s to the island of Guam has resulted in

Accepted Answer

A)  eradication of non-native rats and other undesirable/pest species.
B)  the extirpation of many of the island's bird and reptile species.
C)  a good lesson in biological control.
D)  a new species of hybrids from crossbreeding with a native snake species.
E)  its failure to compete with native species and its quick elimination from the island.

Question 16

Which of the following ecological locations has the greatest species diversity?

Accepted Answer

A)  tundra
B)  deciduous forests
C)  tropics
D)  grasslands
E)  islands

Question 17

Which of the following examples poses the greatest potential threat to biodiversity?

Accepted Answer

A)  replanting, after a clear cut, a monoculture of Douglas fir trees on land that consisted of old-growth Douglas fir, western cedar, and western hemlock
B)  allowing previously used farmland to go fallow and begin to fill in with weeds and then shrubs and saplings
C)  trapping and relocating large predators, such as mountain lions, that pose a threat as they move into areas of relatively dense human populations
D)  importing an Asian insect into the United States to control a weed that competes with staple crops
E)  releasing sterilized rainbow trout to boost the sport fishing of a river system that contains native brook trout

Question 18

Which of the following life history traits can potentially influence effective population size (Ne)?

Accepted Answer

A)  maturation age
B)  genetic relatedness among individuals in a population
C)  family and population size
D)  gene flow between geographically separated populations
E)  All of the options are correct.

Question 19

According to the small-population approach, what would be the best strategy for saving a population that is in an extinction vortex?

Accepted Answer

A)  determining the minimum viable population size by taking into account the effective population size
B)  establishing a nature reserve to protect its habitat
C)  introducing individuals from other populations to increase genetic variation
D)  determining and remedying the cause of its decline
E)  reducing the population size of its predators and competitors

Question 20

Which of the following is a (are)potential disadvantage(s)of movement corridors for wildlife?

Accepted Answer

A)  reduce wildlife-vehicle collisions
B)  route for spread of parasites/disease
C)  promote dispersal and reduce inbreeding
D)  potential increase in predation along corridor
E)  B and D

Exam 56: Conservation Biology and Global Change