Population and Community Ecology Final

Environmental fluctuations are categorized by ecologists into what two primary components?

A) Abiotic and biotic

B) Deterministic (predictable) and Stochastic (unpredictable)

C) Density-dependent and density-independent

D) Growth-based and reproduction-based

Deterministic (predictable) and Stochastic (unpredictable)

How is environmental stochasticity technically defined in population modeling?

A) The predictability cycles of day and night

B) The inability to predict a future state precisely, such that only its probability distribution is known

C) The impact of high population density on birth rates

D) A constant per-capita growth rate over long period

The inability to predict a future state precisely, such that only its probability distribution is known

In a comparison between a population in a constant environment and one in a fluctuating environment (where the mean condition is the same) which statement is generally true?
A) The stochastic population growth rate (𝜆s) will be higher

B) Both populations will reach the exact same asymptotic growth rate

C) The stochastic population growth rate (𝜆s) will be lower (𝜆s < 𝜆c)

D) Environmental stochasticity has no impact on asymptotic growth rate

The stochastic population growth rate (𝜆s) will be lower (𝜆s < 𝜆c)

The value of the stochastic population growth rate depends on which two factors regarding vital rates?

A) How much a vital rate fluctuates and how sensitive the growth rate is to that specific rate

B) the total # of immigrants and the total # of emigrants

C) the initial population vector and the duration of the transient phase

D) the carrying capacity and the level of intraspecific competition

How much a vital rate fluctuates and how sensitive the growth rate is to that specific rate

To determine the long-term stochastic population growth rate, which mathematical method is used after projecting the population over many time steps?

A) the arithmetic mean of annual growth rate

B) the summation of all individuals produced

C) the geometric mean of the population growth rate

D) the square root of the final population density

the geometric mean of the population growth rate

An ecologist decides to build a deterministic population model without incorporating environmental stochasticity. Under which condition is this simplification most justified?

A) When a population is experiencing density dependence

B) When a population is growing rapidly

C) When a population is declining rapidly

D) When fluctuation in vital rates is small

When fluctuation in vital rates is small

What are the two primary outputs calculated through a Population Viability Analysis (PVA)?

 

A) Carrying capacity and interspecific competition coefficients

 

B) Population extinction probability and expected time to extinction

 

C) Initial population density and the number of immigrants

 

D) The ratio of males to females in the next generation

Population extinction probability and expected time to extinction

When determining the quasi-extinction threshold, which of the following is NOT a relevant biological consideration?

 

A. Population genetics

 

B. Life history of the organism (e.g., which stages are being counted)

 

C. Depensatory density dependence

 

D. The phylogenetic age of the species

The phylogenetic age of the species

How does environmental stochasticity generally affect the asymptotic population growth rate (λ_s)?

 

A) It increases the growth rate by providing more resources.

 

B) It has no measurable effect on long-term growth.

 

C) It reduces the asymptotic population growth rate on average.

 

D) It only affects the growth rate during the first generation.

It reduces the asymptotic population growth rate on average.

If a population’s stochastic growth rate is λ_s < 1, what is the ultimate fate of that population if conditions do not improve?

 

A) It will fluctuate indefinitely around a stable mean.

 

B) It will eventually enter a state of asymptotic growth.

 

C) It is guaranteed to go extinct, and the probability of eventual extinction is 1.

 

D. It will eventually stabilise at a small but positive population size.

It is guaranteed to go extinct, and the probability of eventual extinction is 1.

What is the “quasi-extinction threshold” in the context of population management?

 

A. The level of abundance at which a population becomes invasive.

 

B. A pre-specified threshold below which a population is considered practically extinct.

 

C. The maximum number of individuals an environment can support.

 

D. The point where birth rates exactly equal death rates.

A pre-specified threshold below which a population is considered practically extinct

Which of the following is NOT an “ingredient” required to perform a standard Population Viability Analysis?

 

A. Current population size

 

B. How population parameters fluctuate (variance)

 

C. A pre-specified quasi-extinction threshold

 

D. The exact number of predator species in the surrounding community

The exact number of predator species in the surrounding community

Even if a population’s stochastic growth rate is λ_s > 1, it might still face extinction. Why?

 

A. Because λs is always equal to 1 in the long term.

 

B. Because of the chance of extreme random fluctuations caused by environmental stochasticity.

 

C. Because demographic stochasticity is only relevant for populations larger than 10,000.

 

D. Because conservation actions always reduce the growth rate.

Because of the chance of extreme random fluctuations caused by environmental stochasticity.

When a population is resilient to environmental fluctuations, what does this imply?

 

A. The environment has stopped fluctuating.

 

B. The population growth rate has become negative.

 

C. Fluctuations in vital rates have little impact because the growth rate is not sensitive to those specific rates.

 

D. The population has reached its carrying capacity.

Fluctuations in vital rates have little impact because the growth rate is not sensitive to those specific rates.

According to the Central Limit Theorem applied to population modeling, how do the mean and variance of the natural log (ln) of density change over long periods?

 

A. They both decrease exponentially with time.

 

B. The mean increases linearly while the variance remains constant.

 

C. Both the mean natural log density and its variance change linearly with time.

 

D. The mean remains constant while the variance increases exponentially.

Both the mean natural log density and its variance change linearly with time.

Which type of stochasticity refers specifically to the uncertainty resulting from random variation in births and deaths among individuals?

 

A. Environmental stochasticity

 

B. Demographic stochasticity

 

C. Sampling stochasticity

 

D. Genetic stochasticity

Demographic stochasticity

How is demographic stochasticity formally defined in population ecology?

 

A. The predictable seasonal changes in birth rates across an entire population.

 

B. The stochasticity in the fate of individuals within a population at a given time.

 

C. The uncertainty in parameters resulting from limited or imperfect data collection.

 

D. The impact of density-dependent factors on the carrying capacity.

The stochasticity in the fate of individuals within a population at a given time.

What is a key difference between environmental stochasticity and demographic stochasticity?

 

A. Under environmental stochasticity, fates differ between individuals, while under demographic stochasticity, all individuals are affected equally.

 

B. Under environmental stochasticity, vital rate changes are experienced by all individuals equally, whereas under demographic stochasticity, individual fates are different.

 

C. Environmental stochasticity only affects large populations, while demographic stochasticity only affects extinct ones.

 

D. There is no difference; they are two terms for the same random process.

Under environmental stochasticity, vital rate changes are experienced by all individuals equally, whereas under demographic stochasticity, individual fates are different.

When modelling the survival of a cohort of N individuals, each with the same probability of survival p, which distribution describes the number of survivors?

 

A. Bernoulli Distribution

 

B. Poisson Distribution

 

C. Binomial Distribution

 

D. Multinomial Distribution

Binomial Distribution

Why is demographic stochasticity specifically a major concern for conservation biology?

 

A. It only occurs in populations with high genetic diversity.

 

B. It often increases the chance of extinction, especially when population size is small.

 

C. It ensures that the population will always reach a stable stage distribution.

 

D. It prevents the law of large numbers from ever applying to biological systems.

It often increases the chance of extinction, especially when population size is small.

Which statistical principle explains why demographic stochasticity is typically NOT important when population density is high?

 

A. The Central Limit Theorem

 

B. The Bernoulli Principle

 

C. The Principle of Competitive Exclusion

 

D. The Law of Large Numbers, which states the average of outcomes will become close to the expected value as the number of trials increases.

The Law of Large Numbers, which states the average of outcomes will become close to the expected value as the number of trials increases.

In a model tracking individual survival or death over one year, which discrete stochastic process uses only one parameter (the probability of survival)?

 

A. Bernoulli Process

 

B. Poisson Process

 

C. Multinomial Process

 

D. Normal Distribution

Bernoulli Process

True or False

The density dependence is a deterministic process whereas all of the environmental fluctuation is stochastic

FALSE

True or False

All environmental fluctuation is stochastic

FALSE

Which of the following is a common method to estimate survival rate?

A. Capture recapture analysis

B. Life table analysis

C. Analysis of variance

D. Both A and B

Both A and B

Suppose you have three numbers, a, b, and c. You want to take their geometric mean. Which is correct??

A. (a*b*c)^1/3

B. a+b+c/3

C. a*b*c/3

D. (a+b+c)^1/3

(a*b*c)^1/3

To calculate population extinction probability, we need to know the current population density, mean vital rates, and quasi extinction threshold. What else do we need to know?

A. population growth rate

B. Variance in vital rates

C. Stable stage distribution

D. Reproductive value

Variance in vital rates

True or false

Under environmental stochasticity, changes in vital rates are experienced by all individuals equally.

TRUE

True or false

Under demographic stochasticity, fates of individuals are the same among all individuals

FALSE

Which distribution is the most appropriate for modeling transition rates in a stage-structured model when there are three or more possible fates (e.g., remaining in the same stage, growing to a new stage, or dying)?

 

A. Binomial Distribution

 

B. Poisson Distribution

 

C. Multinomial Distribution

 

D. Negative Binomial Distribution

Multinomial Distribution

 

An important assumption of the Poisson distribution when modeling fertility (the number of offspring produced in a fixed window) is that:

 

A. The variance must be significantly higher than the mean.

 

B. The mean and the variance are the same.

 

C. Each birth event is dependent on the previous one.

 

D. It can only be used for individuals that produce exactly two offspring.

The mean and the variance are the same.

If the variance of a population’s fertility term is greater than the mean, which distribution should an ecologist use instead of a Poisson process?

 

A. Negative Binomial Distribution

 

B. Bernoulli Process

 

C. Multinomial Distribution

 

D. Continuous Normal Distribution

Negative Binomial Distribution

Why is it often misguided to suggest a single “universal number” (like 50 or 500) for the population size at which demographic stochasticity becomes critical?

 

A. Because demographic stochasticity is only a theoretical concept with no real-world impact.

 

B. Because the law of large numbers applies equally to all species regardless of size.

 

C. Because we need to know the specific life history and stages of the individuals being counted, as some are more vulnerable than others.

 

D. Because environmental stochasticity always overrides demographic factors.

Because we need to know the specific life history and stages of the individuals being counted, as some are more vulnerable than others.

In the logistic model, what does the parameter "r" (intrinsic population growth rate) represent?

 

A. The population density when the growth rate is zero.

 

B. The maximum per-capita instantaneous growth rate when density is very low.

 

C. The average number of offspring produced by a female in her lifetime.

 

D. The speed of population change at the carrying capacity.

The maximum per-capita instantaneous growth rate when density is very low.

From a biological perspective, what does the term “density dependence” refer to?

 

A. The fact that larger populations always have higher birth rates.

 

B. When vital rates, such as per-capita birth and death rates, are affected by (or are a function of) the population’s density.

 

C. The absolute number of individuals in a population at a single time step.

 

D. The study of how different species interact within the same community.

When vital rates, such as per-capita birth and death rates, are affected by (or are a function of) the population’s density.

What is biologically occurring in a population when it reaches its carrying capacity (k)?

 

A. All reproduction has ceased.

 

B. The birth and death rates have reached a balance, resulting in a net population growth rate of zero.

 

C. All available resources have been completely exhausted, leading to immediate extinction.

 

D. The population has reached its maximum “speed” of change.

The birth and death rates have reached a balance, resulting in a net population growth rate of zero.

How is the logistic equation fundamentally derived in terms of per-capita growth?

 

A. By modifying the exponential per-capita growth rate to decline linearly with population density.

 

B. By assuming the per-capita growth rate increases linearly with time.

 

C. By assuming the per-capita growth rate remains constant regardless of density.

 

D. By assuming birth rates are always ten times higher than death rates.

By modifying the exponential per-capita growth rate to decline linearly with population density.

On a plot of "Per-Capita Population Growth Rate vs. Population Density," what does the line look like for the logistic model?

 

A. A horizontal line.

 

B. A line that increases exponentially.

 

C. A hump-shaped (parabolic) curve.

 

D. A line that declines linearly as density increases.

A line that declines linearly as density increases.

At what population density does the "speed" of population change (the total population growth rate, dn/dt) reach its maximum value?

 

A. When n is near zero.

 

B. When n is equal to the carrying capacity (k).

 

C. When n is at half of the carrying capacity (k/2).

 

D. When n is equal to r.

When n is at half of the carrying capacity (k/2).

If the current population density (n) is greater than the carrying capacity (k), what will happen to the population?

 

A. The per-capita growth rate becomes negative, and the population density decreases.

 

B. The population density will remain the same.

 

C. The carrying capacity will increase to accommodate the extra individuals.

 

D. The population will grow even faster due to compensatory density dependence.

The per-capita growth rate becomes negative, and the population density decreases.

What is the characteristic shape of the curve when population density (n) is plotted against time (t) in a logistic model?

 

A. A sigmoidal (S-shaped) curve.

 

B. A straight line with a positive slope.

 

C. A J-shaped curve that increases forever.

 

D. A parabolic curve that returns to zero after reaching its peak.

A sigmoidal (S-shaped) curve.

When comparing exponential and logistic growth plots, which of the following is TRUE regarding "Growth Rate (speed) vs. Density"?

 

A. Both models show a constant horizontal line.

 

B. Exponential growth shows a parabolic curve, while logistic growth shows a linear increase.

 

C. Exponential growth shows a linear increase, while logistic growth shows a parabolic (hump-shaped) curve.

 

D. Both models show a linear decrease.

Exponential growth shows a linear increase, while logistic growth shows a parabolic (hump-shaped) curve.

When comparing the standard Logistic model to a model including the Allee Effect, what is the primary theoretical difference regarding equilibrium points?

 

A. The Allee model introduces an unstable equilibrium point that acts as a lower threshold

 

B. The Allee model removes the stable carrying capacity found in the Logistic model

 

C. The Allee model assumes the population will always reach a fixed point of zero.

 

D. The Allee model only contains stable equilibrium points

The Allee model introduces an unstable equilibrium point that acts as a lower threshold

Which of the following best describes the “social dysfunction” mechanism that triggers an Allee Effect?

 

A. High densities leading to aggressive territorial behavior.

 

B. The failure of cooperative behaviors, such as feeding, defense, or breeding, at low densities

 

C. A shift from iteroparity to semelparity in response to overcrowding.

 

D. The exhaustion of subsistence as noted by Malthusian theory.

The failure of cooperative behaviors, such as feeding, defense, or breeding, at low densities

How do genetic factors contribute to the Allee Effect in populations experiencing reduced abundance?

 

A. By increasing the mutation rate to adapt to new environments.

 

B. Through inbreeding depression and the “bottleneck effect”

 

C. By eliminating all deleterious recessive alleles from the gene pool.

 

D. By stabilizing the population exactly at its extinction threshold.

Through inbreeding depression and the “bottleneck effect”

Which type of species interaction is characterized by a negative effect on the fitness of both populations involved (-,-)?

 

A. Antagonism

 

B. Competition

 

C. Mutualism

 

D. Commensalism

Competition

In the derivation of the competition model (dN₁/dt = r₁N₁(K₁ − N₁ − α₁₂N₂) / K₁), what does the competition coefficient α₁₂ represent?

 

A. The carrying capacity of the environment for Species 2.

 

B. The effect of Population 1 on Population 2.

 

C. The intrinsic growth rate of Population 1 in the absence of competition.

 

D. The effect of Population 2 on Population 1.

The effect of Population 2 on Population 1.

A "phase plane" in competition modeling is defined as a figure where:

 

A. Two state variables (such as the densities of two different species) are plotted on the x- and y-axes.

 

B. Population density is plotted against time.

 

C. The growth rate (dN/dt) is plotted against population density.

 

D. The derivatives of both populations are always equal to zero.

Two state variables (such as the densities of two different species) are plotted on the x- and y-axes.

What is the technical definition of an "isocline" (or zero-growth isocline) in the competition model?

 

A. The point on a graph where both species immediately go extinct.

 

B. A line or curve on which the derivative of one of the populations is zero.

 

C. A line representing the carrying capacity of both species combined.

 

D. A curve where the densities of both populations remain perfectly equal.

A line or curve on which the derivative of one of the populations is zero.

Character displacement is a theoretical process where competition causes closely related species to:

 

A. Converge on the same traits to use resources more efficiently.

 

B. Evolve different characteristics, allowing them to occupy different niches.

 

C. Go extinct within a few generations.

 

D. Increase their niche overlap until only one species remains.

B. Evolve different characteristics, allowing them to occupy different niches.

.Which term describes the puzzle of why many species with similar resource requirements can coexist in seemingly identical environmental conditions?

 

A. Gause's Law

 

B. The Paradox of Plankton

 

C. The Malthusian Trap

 

D. Environmental Filtering

B. The Paradox of Plankton

Which ecological force acts to make the characteristics of different species more similar to each other because the environment selects against certain traits?

 

A. Environmental Filtering

 

B. Limiting Similarity

 

C. Character Displacement

 

D. Competitive Exclusion

A. Environmental Filtering

What is the theoretical concept of "Limiting Similarity"?

 

A. The idea that there is a maximum level of niche overlap between species that will allow them to continue coexisting.

 

B. The trend where all organisms in a specific environment evolve the same survival strategies.

 

C. The point where two competing species reach the same population density.

 

D. The minimum number of individuals required to avoid an Allee Effect.

The idea that there is a maximum level of niche overlap between species that will allow them to continue coexisting.

In the context of niche theory, the "Realized Niche" is defined as:

 

A. The full range of conditions a species could occupy in the absolute absence of competition.

 

B. The maximum carrying capacity a population can reach.

 

C. The portion of the niche that a species actually utilizes under the pressure of competition and other interactions.

 

D. The specific traits a species evolves through character displacement.

The portion of the niche that a species actually utilizes under the pressure of competition and other interactions.

The "Competitive Exclusion Principle" (Gause's Law) states that two species requiring the same resources:

 

A. Will eventually merge into a single population.

 

B. Cannot stably coexist indefinitely.

 

C. Will always reach a stable equilibrium at half their carrying capacity.

 

D. Will evolve to become mutualists.

Cannot stably coexist indefinitely.

What is the formal definition of mutualism?

 

A. An interaction where one species benefits while the other is neither helped nor harmed

 

B. An ecological interaction between two or more species where each species has a net benefit

 

C. A relationship that must always be symbiotic for both species to survive

 

D. A long-term biological interaction where one species benefits at the expense of another

An ecological interaction between two or more species where each species has a net benefit

Which of the following is true regarding the relationship between "symbiosis" and "mutualism"?

 

A. Symbiosis only occurs between plants and fungi, not animals

 

B. Mutualism is an interaction where both benefit, but it may not always be a symbiotic relationship

 

C. Symbiosis refers only to interactions where both species must benefit

 

D. All mutualistic interactions are classified as symbiotic relationships

Mutualism is an interaction where both benefit, but it may not always be a symbiotic relationship

How is a "Facultative Mutualism" defined in population ecology?

 

A. A relationship where one species provides food while the other provides only protection

 

B. A mutualism that is not essential for the sustainability of either species involved

 

C. A relationship that is essential for the survival of at least one species

 

D. A relationship that eventually leads to the extinction of both species

A mutualism that is not essential for the sustainability of either species involved

In a population model for mutualism, what does it mean if the carrying capacity (Kj) is below zero?

 

A. The interaction strength between the two species is too weak to be measured

 

B. The population cannot persist without help, indicating the mutualism is obligate

 

C. The mutualism is facultative and the species is a superior competitor

 

D. The population has already reached a stable equilibrium point

The population cannot persist without help, indicating the mutualism is obligate

Which of the following is an example of a consumer-resource interaction where the consumer typically does not kill its resource immediately and often lives on or in it?

 

A. Predator-prey interaction

 

B. Host-parasite interaction

 

C. Plant-herbivore interaction

 

D. Trophic feeding interaction

Host-parasite interaction

Which of Holling's functional response curves includes "prey switching" as a stabilizing mechanism, where predators target more abundant species and allow rare prey to recover?

 

A. Type I

 

B. Type II

 

C. Type III

 

D. All functional responses stabilize the system at low prey densities.

Type III

What is the counterintuitive result described by the "Paradox of Enrichment"?

 

A. Increasing the food supply or carrying capacity of the prey can destabilize the system, switching it from a stable equilibrium to a limit cycle.

 

B. Adding nutrients to a system always leads to a higher stable equilibrium for both predators and prey.

 

C. Enriching the environment causes predators to become less efficient at hunting.

 

D. The prey population grows so quickly that it eventually evolves to become a predator itself.

Increasing the food supply or carrying capacity of the prey can destabilize the system, switching it from a stable equilibrium to a limit cycle.

Which biological scenario is most characteristic of a Type II functional response?

 

A. Filter feeders like baleen whales whose consumption rises linearly without a plateau.

 

B. Predators limited by handling time, such as ladybirds eating aphids, where intake decelerates and plateaus as prey density increases.

 

C. Generalist predators that only form search images for prey once they become highly abundant.

 

D. Organisms that consume resources at an infinite rate regardless of handling time.

Predators limited by handling time, such as ladybirds eating aphids, where intake decelerates and plateaus as prey density increases.

The "Paradox of Biological Control" suggests that introducing a highly efficient predator (one with a high capacity to convert food into offspring) can lead to:

 

A. A permanent, stable reduction of the pest species.

 

B. The predator switching to a different, non-target resource immediately.

 

C. A sudden and large outbreak of the pest species due to destabilized population dynamics.

 

D. The complete eradication of all species in the local community.

A sudden and large outbreak of the pest species due to destabilized population dynamics.

What is a key biological distinction of a Type I functional response?

 

A. It is the most common response type in nature and is driven by predator learning.

 

B. It includes a sigmoidal curve that protects rare prey species.

 

C. It assumes handling time is negligible and consumption is driven solely by the encounter rate, such as in baleen whales filtering krill.

 

D. It is a destabilizing mechanism because prey can always escape regulation at low densities.

It assumes handling time is negligible and consumption is driven solely by the encounter rate, such as in baleen whales filtering krill.

What is the definition of a trophic cascade?

 

A. A process where nutrients determine the abundance of top predators.

 

B. A mechanism in which predators limit the density or behavior of their prey, and reduced prey, in turn, enhance the survival of the next lower trophic level.

 

C. A group of species that rely on the same resource and ecological niche.

 

D. An interaction where two species compete for the same food source without preying on each other.

A mechanism in which predators limit the density or behavior of their prey, and reduced prey, in turn, enhance the survival of the next lower trophic level.

In the shark-seal-fish example of intraguild predation, why might an increase in shark abundance actually increase fish production?

 

A. Because sharks provide a source of nutrients that fish need to grow.

 

B. Because sharks prey on seals, and seals are also predators of the fish.

 

C. Because sharks and fish eventually form a symbiotic relationship.

 

D. Because fish populations grow faster when they are under the stress of predation.

Because sharks prey on seals, and seals are also predators of the fish.

In the classic example involving sea otters, sea urchins, and giant kelp, what is the result of removing sea otters from the system?

 

A. Kelp abundance increases because sea urchins have no predators.

 

B. The system remains stable because sea urchins do not eat kelp.

 

C. Sea urchin populations increase and decimate the kelp forest.

 

D. Sea urchins go extinct due to a lack of competition.

Sea urchin populations increase and decimate the kelp forest.

How is "Intraguild Predation" formally defined?

 

A. Predation that occurs between species that do not share any common resources.

 

B. Predation on a potential competitor that relies on the same resource guild.

 

C. A relationship where a predator and prey eventually become mutualists.

 

D. The total sum of all predatory interactions within a single trophic level.

Predation on a potential competitor that relies on the same resource guild.

true or false

Logistic growth includes density dependence

TRUE

true or false

Logistic growth includes compensatory density dependence

True

true or false

allee effect is a density dependent process

TRUE, its depensatory density dependent bc as density increases, fitness/survival/repro increases

true or false

Under the allee effect, vital rates remain constant

FALSE

Competition reduces the vital rates of all individuals within a given stage. This is an example of

a) contest competition

b) interference competition

c) scramble competition

d) spelling competition

scramble competition

Isocline for the competition model are

a) the line on which the derivatives for both populations are zero

b) the line on which the derivative of one of the populations is zero

c) the plot of two states on x and y axis

d) the plot of the densities against time

the line on which the derivative of one of the populations is zero

The two important forces that influence the traits of organisms are

a) limited similarity and environmental filtering

b) density dependence and exponential growth

c) scramble competition and contest competition

d) environmental stochasticity and environmental periodicity

limited similarity and environmental filtering

true or false

the size of the circle (amplitude of cycle) observed on the phase plane depends on the initial condition

TRUE

true or false

under the simple Lotka-Volterra predator prey model, if we remove predator (we still have some prey in a system) we expect prey to grow exponentially

true

what does the Holling’s functional response curve show?

a) the total amount of prey consumed by all predators in a population

b) the rate at which prey is consumed by a single predator

c) the population growth rate of predators

the rate at which prey is consumed by a single predator

Difference between Holling’s Type II functional response curve and type III functional response curve is

a) type III curve includes the satiation of a predator

b) type III curve includes cannibalism

c) type III curve includes prey switching by predators

d) type III curve includes starvation of prey

type III curve includes prey switching by predators

true or false

the two results (stable equilibrium and limit cycle) were obtained with different equations

false

true or false

competition promotes co-existence of species

true?

true or false

predation can promote co-existence of species

TRUE

which one of the infections is not contagious?

a) rabies

b) covid 19

c) malaria

d) common cold

malaria

which of the following is closely related to the basic reproductive number?

a) net reproductive rate

b) reproductive value

c) generation time

d) population growth rate

net reproductive rate

the second derivative of state variable with respect to location is proportional to the first derivative with respect to time. it represents

a) advection

b) diffusion

c) logistic growth

d) long distance dispersal

diffusion

per-capita population growth rate of logistic growth against population density is

a) a straight line with a negative slope

b) a parabola

c) a sigmoidal curve

d) none of the above

a straight line with a negative slope

population growth rate (dn/dt) of logistic growth against population density is

a) a straight line with a negative slope

b) a parabola

c) a sigmoidal curve

d) none of the above

a parabola

population growth rate (dn/dt) is

a) the speed at which population density changes

b) 0 when population density does not change over time

c) negative when population density declines

d) all of the above

all of the above

Yes or No

Can we ever catch animals greater than MSY in any given year

yes