Ecology Chapter 9,10,11, 12


Terms in this set (...)

Density is defined as
the number of individuals per unit area
Caughly's research on the distribution of three different species of Australian kangaroos (Macropus giganteus, M. fuliginosus, and M. rufus) suggests the
physical environment limits the distribution of the kangaroos.
Which statement about organisms' "niches" is false?
In the laboratory, two species with identical niches are especially easy to maintain in a mixed culture.
The tiger beetle Cicindela longilabris inhabits higher latitudes and elevations than other North American tiger beetles; Schultz, Quinlan, and Hadley concluded that all of the following factors contributed to these cooler environmental preferences except
increased water proofing.
In order to determine whether a species is common or rare, ecologists use all of the following criteria except:
evolutionary existence
Which of the following word pairs are mismatched
random distribution; aggressive interaction
'Rarity I' can be described as:
extensive range, broad habitat tolerances, small local populations
'Rarity II' can be described as
extensive range, narrow habitat tolerances, and large local populations.
'Extreme Rarity' can be described as
restricted range, narrow habitat tolerances, and small local populations.
Which of the following are characteristics of a population?
A) consists of a single species
B) has an age distribution
C) has a birth rate
D) has an emigration rate
Donald Phillips and James MacMahon showed that the distribution pattern of creosote bush, Larrea tridentata, changes in the following sequence as they grow
clumped, random, regular
Caughley found the distributions of the three largest kangaroo species in Australia are determined by
According to the results of Philips and MacMahon, which of the following relationships of variance to mean shrub density would be expected for young creosote bushes?
The creosote bush (Larrea tridentate) can have a random, clumped, or regular distribution pattern.
Often small scale distribution patterns gathered from mountain gradients can be used to draw conclusions about large scale distribution patterns.
In general, research indicates that as the average body mass of an organism increases, population density also increases.
Often an organism with a broad habitat tolerance is called a generalist
Research by Hubble and Johnson showed that aggressive social interactions among stingless bees in the tropical dry forests of Costa Rica can produce and enforce a clumped distribution.
Chapter 10
Type II survivorship curve indicates
equal chance of dying at any age
Type I survivorship curve indicates
low juvenile mortality and high mortality in older adults.
Type III survivorship curve indicates
high juvenile mortality and low mortality in older adults.
Humans would best be represented by which of the following survivorships curves?
Organisms that produce many offspring would best be characterized by which of the following
a concave survivorship curve
The age distribution of a population can reveal
growth potential, survivorship, and reproduction
Which of the following are mismatched?
nx : mortality rate
The 'net reproduction rate' equals
∑ lx mx
Which of the following statements regarding 'mean generation time' is false?
It can be used to calculate the geometric growth rate.
The 'mean generation time' of a population equals
(∑x lxmx)/R0
Which of the following cannot be determined using a fecundity schedule combined with a life table?
dispersal rates
Which of the following equations best represents the per capita rate of increase?
r = (ln R0)/T
Which of the following equations best represents the geometric rate of increase?
λ = (Nt+1)/N
The Africanized honeybee stopped spreading southward through South America by about 1983 in response to
unfavorable climatic factors.
A group of subpopulations living in spatially isolated patches connected by exchange of individuals among patches is called a(n)
Studies by Korpimäki and Norrdahl in western Finland showed that kestrel and owl densities closely follow variation in vole densities with little delay or lag time. They attributed this rapid numerical response to the
nomadic nature of the kestrel and owl populations.
Roland, Keyghobadi, and Fownes found in smaller meadow habitat, the Rocky Mountain Parnassian butterfly
populations are smaller and individuals are more likely to disperse out of the patch
Which of the following indicates a population in decline?
R0 = 0.601
When using a significance level of 0.05, how often will you reject hypotheses that are actually correct?
5% of the time or less
Calculate the generation time given the following population data:
R0 = 0.601, r = - 0.05, ∑xlxmx = 6.4, mx = 0.96
Fecundity is another term for the net reproductive rate
The geometric rate of increase can be used to estimate changes in population size in species with non-overlapping generations.
The per capita rate of increase can be used to estimate changes in population size in species with non-overlapping generations
Although the dispersal rate of Africanized bees is impressive, it still pales in comparison to the dispersal rate of the collard dove.
Many sedentary organisms have a 'dispersing stage' and rely on vectors such as animals, water, or wind to aid in their spread
The geometric rate of increase cannot be a negative number.
The per capita rate of increase cannot be a negative number
Nt = N0 λt represents
geometric population growth
dN/dt = rmaxN [(K - N)/K] represents
logistic growth
dN/dt = rmaxN represents
exponential population growth
An annual plant when initially colonizing an area will probably demonstrate
geometric population growth.
The exponential population growth equation can be used for
both populations with overlapping generations, populations experiencing continuous growth, and populations with nonpulsed reproduction.
The factors that determine carrying capacity include all of the following except:
None of the choices are correct.
N/K' for a population can represent
environmental resistance
Which of the following is/are mismatched
Nt = annual growth rate
Density dependent factors include all of the following except:
Human populations are clumped on a large scale with the greatest concentration in
If the age distribution diagram is bottom heavy or pyramidal in shape, this indicates that the population is
growing rapidly.
If the age distribution diagram is bell shaped or the number of individual in each age class is evenly distributed, this indicates that the population is
If the age distribution diagram has the smallest concentration of individuals in the bottom portion or is considered to be an urn shape, this indicates that
the population is declining.
Which of the following statements is/are true?
Population growth in humans is exponential.
The best model for population growth of an annual plant like Phlox drummondii is
geometric growth.
In the logistic model of population growth if r>0 then
In the logistic model of population growth if r<0 then
both the population declines and N>K
In the most basic terms, a population's growth is a function of births and deaths
In a logistic model, when N = K the population stops growing and r = 0
The biotic potential of an organism produces the leveling off at carrying capacity in the logistic growth curve
Occasionally, density independent factors can influence populations in a density dependent manner.
Logistic growth has been documented in which of the following populations?
All choices are correct:
A) Eurasian collared dove
B) barnacle, Balanus balanoides
C) yeast, Saccharomyces cerevisiae
D) Northern elephant seal
A polymorphic locus is one that
occurs in a population as more than one allele
Which of the following observations can be explained by the energetic limitation of an organism's total reproductive effort?
Darters that lay many eggs lay smaller eggs, on average.
The number of eggs laid by a female is called her
Seeds bearing eliasomes are likely to be dispersed by
A "forb" is a(n)
herbaceous, but non-graminoid, plant species.
Which of the following environments for germinating seed is most likely to favor a plant species that makes many small seeds, compared to one that makes fewer larger seeds?
Because natural selection has shaped fish life histories,
Both fish species with high adult mortality tend to mature at a younger age and fish species with high adult mortality tend to invest relatively large amounts of energy in reproduction are true
The "K" in "K-selection" comes from the
"K" in the logistic growth equation.
Which of the following is NOT a characteristic favored by K-selection?
many, small offspring
In Grime's classification, stress-tolerant plants
conserve nutrients and water.
Among fish species, an "opportunistic" life history is characterized by
low juvenile survival, low number of offspring, and early maturity.
Grime's classification of plant life histories focuses attention on
stress and disturbance.
A fish maturing late with large body size and producing many small offspring would be said to have a(n)
periodic life history
As a fraction of adult mass, the mass of offspring at independence tends to be largest in
altricial birds
Riparian" refers to plant communities occurring
in transitions between riverbanks and upland areas.
Which of the following is NOT true of riparian plant communities?
low species diversity, compared to surrounding terrestrial communities
The study of the relationship between climate and the timing of ecological events is called
Which statement about the impact of dams on cottonwood forests is false
By reducing flooding downstream, damming improves cottonwood seed germination.
The principle of allocation states
if an organism uses energy for one function it reduces the amount of energy available for other functions
Which of the following influence the number and size of seeds produced by plants?
All of the choices are correct.
According to research by Westoby, Leishman, and Lord, plants that disperse their seeds in different ways tend to produce seeds of different sizes. Which is the correct order of seed mass from smallest to largest?
unassisted, adhesion-adapted, ant-dispersed, scatterhoarded
Which of the following are characteristics favored by K selection?
Rates of gene flow can be estimated from similarity in allele frequencies among populations.
Life histories typical of r-selection are most likely to evolve where species populations are near carrying capacity much of the time.