Question 1

Which of the following equations is a zero-growth isocline?

Accepted Answer

A zero-growth isocline is an equation where the growth rate of a population equals zero, indicating that the population size remains constant. Choice A represents a situation where the population size (N) is equal to the carrying capacity (K) divided by a factor, suggesting no further growth, hence a zero-growth isocline.

Question 2

If an individual of species 2 has a greater effect on species 1 than the reverse, which of the following would be TRUE?

Accepted Answer

If species 2 has a greater effect on species 1, then the competition coefficient for species 1 when competing with species 2 (F1F1F1S1αF1F1F10) will be less than 1, while the competition coefficient for species 2 when competing with species 1 (F1F1F1S1βF1F1F10) will be greater than 1. Thus, the only option that fits this scenario is D, where both coefficients meet those criteria.

Question 3

In Morin's competition experiment, ponds contained tadpoles of three species and a species of newt. Newts in increasing numbers were added to ponds containing the tadpoles. How did the number of newts affect competition among tadpoles?

Accepted Answer

Morin found that as the number of newts in ponds increased, the outcome of competition between the tadpole species was reversed. Initially, one species was dominant over the others, but as newt predation increased, the dominant species was more vulnerable to predation and the less dominant species increased in abundance. This demonstrates that predation by newts can alter the outcome of competition among tadpoles.

Question 4

Imagine a population of 600 mice and 350 chipmunks. The chipmunks and mice eat some of the same food, but the food to support 1,000 mice would support only 300 chipmunks. What would $\alpha$ and $\beta$ be for this population in which mice are species 1 and chipmunks are species 2?

Accepted Answer

To calculate F1F1F1S1F1F1F10 and F1F1F1S1F1F1F10, we need to use the formula:

F1F1F1S1F1F1F10 = food required by mice / food required by 1000 individuals of species 2 
F1F1F1S1F1F1F10 = food required by species 2 / food required by 1000 individuals of mice

Given: 
Population of mice (species 1) = 600 
Population of chipmunks (species 2) = 350 
Food required for 1000 mice = food required for 300 chipmunks 
Therefore, food required for 1 mouse = food required for 0.5 chipmunks

Now, we can calculate: 
F1F1F1S1F1F1F10 = food required by mice / food required by 1000 individuals of species 2 
= (600 * food required for 1 mouse) / (350 * food required for 1 chipmunk) 
= 1.714

F1F1F1S1F1F1F10 = food required by species 2 / food required by 1000 individuals of mice 
= (350 * food required for 1 chipmunk) / (600 * food required for 1 mouse) 
= 0.294

Thus, the answer is A: F1F1F1S1F1F1F10 = 3.3; F1F1F1S1F1F1F10 = 0.3.

Question 5

In David Tilman's experiments with the diatoms Cyclotella and Asterionella, when the diatoms were grown at silicon/phosphorus ratios between 6 and 90, why did the two species coexist?

Accepted Answer

The diatoms Cyclotella and Asterionella coexisted because one species was limited by phosphorus, and the other was limited by silicon. At lower silicon/phosphorus ratios, Cyclotella was favored because it was better able to compete for limited silicon. At higher ratios, Asterionella was favored because it was better able to compete for limited phosphorus. Therefore, the two species were able to coexist by partitioning their resource use.

Question 6

In Lotka-Volterra competition models, the variable K represents the

Accepted Answer

The variable K in Lotka-Volterra competition models represents the carrying capacity, which is the maximum population size that a particular environment can sustain.

Question 7

The resource requirements of two plant species, A and B, have been carefully studied. Researchers have determined the levels of a particular resource that will support equilibrium levels of each species. Species A needs more of this resource to maintain equilibrium than does species B. When these two species are set in competition (under conditions in which this resource is limiting), what is likely to happen to the populations of species A and B?

Accepted Answer

Since species A requires more of the limiting resource than species B in order to maintain equilibrium, when they are set in competition for the same resource, species B is more likely to outcompete and displace species A.

Question 8

In experiments with competitive barnacle species distributed along upper and lower intertidal zones, researchers found a trade-off between ability to _____ and ability to _____.

Accepted Answer

The answer of In experiments with competitive barnacle species distributed...

Question 9

Which of the following make(s) coexistence of species 1 and 2 more likely?

Accepted Answer

The answer of Which of the following make(s) coexistence of...

Question 10

Graphical models of competition tell us that

Accepted Answer

Coexistence of two competing species is most likely if intraspecific competition is stronger than interspecific competition.

Question 11

Connell's research on competition between the rock barnacle and Poli's stellate barnacle in upper and lower intertidal zones is an example of

Accepted Answer

Connell's research involved manipulating the presence of one barnacle species in different parts of the intertidal zone in order to study the competition between the two species. Therefore, it is an example of a manipulative experiment.

Question 12

In Connell's experiment with upper and lower intertidal barnacles, the rock barnacle excluded the Poli's stellate barnacle from deeper water because

Accepted Answer

The rock barnacle grew faster and physically displaced the Poli's stellate barnacle from the rock substrate, effectively excluding it from deeper water.

Question 13

In Lotka-Volterra population models, $\alpha$₁₂ and $\alpha$₂₁ are referred to as

Accepted Answer

The answer of In Lotka-Volterra population models, $\alpha$₁₂ and $\alpha$₂₁...

Question 14

In the logistic growth equation $\frac { d N } { d t } = r N \left( 1 - \frac { N } { K } \right)$ , the variable r represents the

Accepted Answer

The variable r represents the intrinsic growth rate, which is the rate at which a population would grow in the absence of any limiting factors (such as competition, predation, or resource availability). Therefore, choice (B) is the best choice. Choice (A) represents the maximum population size that can be supported in a particular environment, choice (C) represents the actual size of the population, and choice (D) is not a variable represented in the logistic growth equation.

Question 15

(Figure 16.8c and d) Compare the outcomes of competition between species 1 and 2 in the figure. Justify your answers.

Accepted Answer

The answer of  (Figure 16.8c and d) Compare the...

Question 16

In Lotka-Volterra competition models, what does the term $\alpha$_1,2 N₂ represent?

Accepted Answer

This term represents the reduction of species 1's carrying capacity by individuals of species 2 in the competition model.

Question 17

In the example of competition dynamics with longleaf pine (Pinus palustris) and other woody plants, fire suppression

Accepted Answer

Fire is a natural disturbance that helps to eliminate less fire-adapted species, allowing dominant species like longleaf pine and wiregrass to thrive. Fire suppression, in turn, allows the persistence of these less fire-adapted species, leading to increased competition and decreased biodiversity.

Question 18

A zero-growth isocline is best defined in terms of

Accepted Answer

A zero-growth isocline represents a line in a graph that separates regions of population growth from regions of population decline. This line indicates the population size at which the growth rate of a population is zero, and is best defined in terms of population.

Question 19

Populations approach a stable equilibrium when

Accepted Answer

A population approaches a stable equilibrium when its growth rate nears zero, meaning that the birth rate equals the death rate and there is no net migration. Option A is incorrect because a depleted resource would not support population growth, and there would be no equilibrium to approach. Option B is incorrect because although resources may be plentiful, the population growth rate still needs to slow down for the population to approach equilibrium. Option D is incorrect because populations exceeding carrying capacity would experience a decline in resources and an increase in competition, which would lead to a reduction in population size rather than an equilibrium.

Question 20

Competition coefficients can be used to

Accepted Answer

The answer of Competition coefficients can be used to
...

Quiz 16: Competition

Which of the following equations is a zero-growth isocline?

If an individual of species 2 has a greater effect on species 1 than the reverse, which of the following would be TRUE?

In Morin's competition experiment, ponds contained tadpoles of three species and a species of newt. Newts in increasing numbers were added to ponds containing the tadpoles. How did the number of newts affect competition among tadpoles?

Imagine a population of 600 mice and 350 chipmunks. The chipmunks and mice eat some of the same food, but the food to support 1,000 mice would support only 300 chipmunks. What would $\alpha$ and $\beta$ be for this population in which mice are species 1 and chipmunks are species 2?

In David Tilman's experiments with the diatoms Cyclotella and Asterionella, when the diatoms were grown at silicon/phosphorus ratios between 6 and 90, why did the two species coexist?

In Lotka-Volterra competition models, the variable K represents the

In experiments with competitive barnacle species distributed along upper and lower intertidal zones, researchers found a trade-off between ability to _ and ability to _.

Which of the following make(s) coexistence of species 1 and 2 more likely?

Graphical models of competition tell us that

Connell's research on competition between the rock barnacle and Poli's stellate barnacle in upper and lower intertidal zones is an example of

In Connell's experiment with upper and lower intertidal barnacles, the rock barnacle excluded the Poli's stellate barnacle from deeper water because

In Lotka-Volterra population models, $\alpha$ ₁₂ and $\alpha$ ₂₁ are referred to as

In the logistic growth equation $\frac { d N } { d t } = r N \left( 1 - \frac { N } { K } \right)$ , the variable r represents the

(Figure 16.8c and d) Compare the outcomes of competition between species 1 and 2 in the figure. Justify your answers.

In Lotka-Volterra competition models, what does the term $\alpha$ _1,2 N₂ represent?

In the example of competition dynamics with longleaf pine (Pinus palustris) and other woody plants, fire suppression

A zero-growth isocline is best defined in terms of

Populations approach a stable equilibrium when

Competition coefficients can be used to

Quiz 16: Competition

Which of the following equations is a zero-growth isocline?

If an individual of species 2 has a greater effect on species 1 than the reverse, which of the following would be TRUE?

In Morin's competition experiment, ponds contained tadpoles of three species and a species of newt. Newts in increasing numbers were added to ponds containing the tadpoles. How did the number of newts affect competition among tadpoles?

Imagine a population of 600 mice and 350 chipmunks. The chipmunks and mice eat some of the same food, but the food to support 1,000 mice would support only 300 chipmunks. What would α\alphaα and β\betaβ be for this population in which mice are species 1 and chipmunks are species 2?

In David Tilman's experiments with the diatoms Cyclotella and Asterionella, when the diatoms were grown at silicon/phosphorus ratios between 6 and 90, why did the two species coexist?

In Lotka-Volterra competition models, the variable K represents the

In experiments with competitive barnacle species distributed along upper and lower intertidal zones, researchers found a trade-off between ability to _____ and ability to _____.

Which of the following make(s) coexistence of species 1 and 2 more likely?

Graphical models of competition tell us that

Connell's research on competition between the rock barnacle and Poli's stellate barnacle in upper and lower intertidal zones is an example of

In Connell's experiment with upper and lower intertidal barnacles, the rock barnacle excluded the Poli's stellate barnacle from deeper water because

In Lotka-Volterra population models, α\alphaα 12 and α\alphaα 21 are referred to as

In the logistic growth equation dNdt=rN(1−NK) \frac { d N } { d t } = r N \left( 1 - \frac { N } { K } \right) dtdN​=rN(1−KN​) , the variable r represents the

(Figure 16.8c and d) Compare the outcomes of competition between species 1 and 2 in the figure. Justify your answers.

In Lotka-Volterra competition models, what does the term α\alphaα 1,2 N2 represent?

In the example of competition dynamics with longleaf pine (Pinus palustris) and other woody plants, fire suppression

A zero-growth isocline is best defined in terms of

Populations approach a stable equilibrium when

Competition coefficients can be used to

Imagine a population of 600 mice and 350 chipmunks. The chipmunks and mice eat some of the same food, but the food to support 1,000 mice would support only 300 chipmunks. What would $\alpha$ and $\beta$ be for this population in which mice are species 1 and chipmunks are species 2?

In experiments with competitive barnacle species distributed along upper and lower intertidal zones, researchers found a trade-off between ability to _ and ability to _.

In Lotka-Volterra population models, $\alpha$ ₁₂ and $\alpha$ ₂₁ are referred to as

In the logistic growth equation $\frac { d N } { d t } = r N \left( 1 - \frac { N } { K } \right)$ , the variable r represents the

In Lotka-Volterra competition models, what does the term $\alpha$ _1,2 N₂ represent?