Ch.53
In the figure, which of the following survivorship curves implies
that an animal may lay many eggs, of which a regular number die each
year on a logarithmic scale?
A) curve A
B) curve B
C) curve C
D) curves A or C
B) curve B
In the figure, which of the following survivorship curves most
applies to humans living in developed countries?
A) curve
A
B) curve B
C) curve C
D) curve A or curve B
A) curve A
Using the table, how would you describe the population dynamics of
the Eurasian lizard, Z. vivipara?
A) The population is
increasing.
B) The population is decreasing.
C) The population is stable.
D) The table does not provide
this information.
A) The population is increasing.
Using the table, determine which age class year would cause the
largest decline in the resulting population growth, if it were wiped
out by disease.
A) age class year 1
B) age class year 2
C) age class year 3
D) age class year 4
A) age class year 1
Suppose researchers marked 800 turtles and later were able to trap a
total of 300 individuals in that population, of which 150 were marked.
What is the estimate for total population size?
A) 200
B) 1,050
C) 1,600 D) 2,100
C) 1,600
Looking at the figure, what factor is contributing significantly to stabilizing the population size over time?
A) only I
B) only II
C) only III
D) only II and III
C) only III
Which of the following assumptions must be made regarding the mark-recapture estimate of population size?
individuals have been added by birth or eliminated by death during the course of the estimate.
A) I only
B) II only
C) I and II only
D) I, II,
and III
D) I, II, and III
Which of the following is the most important assumption for the
mark-recapture method to estimate the size of wildlife
populations?
A) More individuals emigrate from, as opposed to
immigrate into, a population.
B) Over 50% of the marked
individuals were trapped during the recapture phase.
C) There is a 50:50 ratio of males to females in the population
before and after trapping and recapture.
D) Marked individuals
have the same probability of being recaptured as unmarked individuals
during the recapture phase.
D) Marked individuals have the same probability of being recaptured as unmarked individuals during the recapture phase.
Which curve best describes survivorship in marine mollusks? A)
A
B) B
C) C
D) E
D) E
Which curve best describes survivorship in elephants? A) A
B)
B
C) C
D) E
A) A
To measure the population of lake trout in a 250-hectare lake, 400
individual trout were netted and marked with a fin clip, then returned
to the lake. The next week, the lake was netted again, and out of the
200 lake trout that were caught, 50 had fin clips. Using the
mark-recapture estimate, the lake trout population size could be
closest to which of the following?
A) 200
B) 400
C)
1,600
D) 80,000
C) 1,600
Long-term studies of Belding's ground squirrels show that immigrants
move nearly 2 kilometers from where they are born and become 1%-8% of
the males and 0.7%-6% of the females in other populations. On an
evolutionary scale, why is this significant?
A) These immigrants
make up for the deaths of individuals, keeping the other populations' size
stable.
B) These immigrants provide a source of genetic
diversity for the other populations.
C) Those individuals that
emigrate to these new populations are looking for less crowded
conditions with more resources.
D) Gradually, the populations of
ground squirrels will move from a clumped to a uniform population
pattern of dispersion.
Answer: B
B) These immigrants provide a source of genetic diversity for the other populations.
In the accompanying life table of a hypothetical population, what are
the missing values for lx (y and z)? lx = the proportion alive at the
start of year (age specific survivorship rate).
A) y = 0.5, z =
0.5
B) y = 1.0, z = 0.5
C) y = 0.5, z = 0.1
D) y = 1.0, z = 0.2
C) y = 0.5, z = 0.1
An ecologist recorded 12 white-tailed deer, Odocoileus virginianus,
per square kilometer (km2) in one woodlot and 20 km2 in another
woodlot. What was the ecologist comparing? A) density
B) dispersion
C) carrying capacity
D) range
A) density
Uniform spacing patterns in plants such as the creosote bush are most
often associated with ________.
A) patterns of high
humidity
B) the random distribution of seeds
C) competitive interaction between individuals of the same population D) the concentration of nutrients within the population's range
C) competitive interaction between individuals of the same population
Which of the following groups would be most likely to exhibit uniform
dispersion? A) red squirrels, who actively defend territories
B)
cattails, which grow primarily at edges of lakes and streams
C)
dwarf mistletoes, which parasitize particular species of forest tree
D) lake trout, which seek out cold, deep water high in dissolved oxygen
A) red squirrels, who actively defend territories
Which of the following examples would most accurately measure the
dispersion of a population being studied?
A) counting the number
of times a one-kilometer transect is intersected by tracks of red
squirrels after a snowfall
B) measuring the distance between
several burrows within a large prairie dog colony in a
Age (years) x
Number alive at start of year nx
lx
1
100
1.0
2
50
0.5
3
50
y
4
10
z
grassland
C) measuring the average distance between
individuals and their nearest neighbor, and then analyzing the
variation and comparing those measurements at larger scales
D)
counting the number of zebras from airplane census observations
C) measuring the average distance between individuals and their nearest neighbor, and then analyzing the variation and comparing those measurements at larger scales
Which of the following is the best natural example of a uniform
pattern of dispersion? A) bees collecting pollen in a wildflower
meadow
B) moss spores floating in the wind to new locations of a
forest
C) territorial songbirds in a mature forest during mating season
D) mushrooms growing on the floor of an old growth forest
D) mushrooms growing on the floor of an old growth forest
Which statement best explains survivorship curve B?
A) It is
likely a species that provides little postnatal care, but lots of care
for offspring during midlife as indicated by increased
survivorship.
B) This curve is likely for a species that
produces lots of offspring, only a few of which are expected to
survive.
C) It is likely a species where no individuals in the
cohort die when they are at 60-70% relative age.
D) Survivorship
can only decrease; therefore, this curve could not happen in nature.
D) Survivorship can only decrease; therefore, this curve could not happen in nature.
Which of the following examples are plausible explanations for a population that would produce curve A in the figure?
I. II. III.
Ongoing predation of rabbits throughout their lives Susceptibility of older humans to heart disease High seedling mortality in sunflowers
A) I only
B) II only
C) I and II
D) II and III
B) II only
Imagine that you are managing a large game ranch. You know from historical accounts that a species of deer used to live there, but they have been extirpated. After doing some research to determine what might be an appropriately sized founding population, you reintroduce them. You then watch the population increase for several generations, and graph the number of individuals (vertical axis) against the number of generations (horizontal axis). With no natural predators impacting the population, the graph will likely appear as ________.
A) a diagonal line, getting higher with each generation B) an
"S" that ends with a vertical line
C) an upside-down
"U"
D) a "J," increasing with each generation
D) a "J," increasing with each generation
In the figure, which of the arrows represents the carrying capacity?
A) arrow A
B) arrow B
C) arrow C
D) Carrying capacity cannot be found in the figure because species under density-dependent control never reach carrying capacity.
C) arrow C
32) Which statements about K are correct?
A) only I and III
B) only II and IV
C) only I, II, and
III
D) only II, III, and IV
C) only I, II, and III
As N approaches K for a certain population, which of the following
outcomes is predicted by the logistic equation?
A) The
population growth rate will not change.
B) The population growth
rate will approach zero.
C) The population size will increase exponentially.
D) The
carrying capacity of the environment will increase.
B) The population growth rate will approach zero.
Which of the following causes populations to shift most quickly from
an exponential to a logistic population growth?
A) favorable
climatic conditions
B) removal of predators
C) decreased death rate
D) competition for resources
D) competition for resources
Which of the following graphs best illustrates the growth curve of a small population of rodents that has increased to a static carrying capacity?
D
18) Which of the following scenarios would provide the most accurate data on population density?
A) Count the number of nests of a particular species of songbird and multiply this by a factor that extrapolates these data to actual animals.
B) Count the number of pine trees in several randomly selected 10-meter-square plots and extrapolate this number to the fraction of the study area these plots represent.
C) Use the mark-recapture method to estimate the size of the population.
D) Calculate the difference between all of the immigrants and emigrants to see if the population is growing or shrinking.
B) Count the number of pine trees in several randomly selected 10-meter-square plots and extrapolate this number to the fraction of the study area these plots represent.