Question 1

How might population density affect life history?

Accepted Answer

A high population density can imply severe competition for resources. This could increase the mortality rate of offspring by limiting the number of offspring a female can produce, the resources available to the offspring to ensure their survival, or both.

Question 2

Topic: semelparity and iteroparity
Difficulty: medium
Lobelia telekii and its relative, L. keniensis, both grow on Mount Kenya in Africa. L. telekii grows on dry rocky slopes whose resources for reproduction (particularly moisture) are highly variable in time and space. L. keniensis is found in moist valley bottoms with more stable moisture supplies. Which species is semelparous?

Accepted Answer

A)  L. telekii 
B)  L. keniensis 
A)  L. telekii 
B)  L. keniensis A

Question 3

Examine the equation for the coefficient of determination (), especially the total sums of squares. If we hold the error sums of squares constant, will the slope of the relation influence the value? Why or why not?

Accepted Answer

Yes, because if the slope is closer to a horizontal line, the total sums of squares will always be small. This will always reduce the value, even with the error sums of squares held constant.
Ecology Today: Connecting the Concepts

Question 4

Which does NOT have slow life history attributes?

Accepted Answer

A)  oak tree 
B)  sea urchin 
C)  elephant 
D)  giant tortoise 
E)  bald eagle 
A)  oak tree 
B)  sea urchin 
C)  elephant 
D)  giant tortoise 
E)  bald eagle

Question 5

Use this figure to answer questions 27 and 28.
  
-According to the figure, what are the implications of producing five versus eight eggs? Which option should be favoured by natural selection?

Accepted Answer

The number of chicks fledged is the same

Question 6

Some marine snails (species L) produce large numbers of small eggs that are shed into the sea, hatch at an early stage of development, and feed on microscopic plants. Other marine snails (species S) produce few eggs that are retained for a long time within the body of the mother snail in a brood pouch, hatch at an advanced stage of development, and immediately begin to feed on the surfaces of large plants like the adults. If a biologist discovers approximately equal numbers of adults of species L and S in the same area over many generations, which of the following is most likely?

Accepted Answer

A)  Young that are cared for by parents until they reach a more advanced stage have a greater chance of survival. 
B)  Approximately the same percentage of young produced by each species survive to maturity. 
C)  Organisms that produce a greater number of offspring will likely replace organisms with fewer offspring. 
D)  The young of species L grow more rapidly than the young of species S. 
A)  Young that are cared for by parents until they reach a more advanced stage have a greater chance of survival. 
B)  Approximately the same percentage of young produced by each species survive to maturity. 
C)  Organisms that produce a greater number of offspring will likely replace organisms with fewer offspring. 
D)  The young of species L grow more rapidly than the young of species S.

Question 7

Tropical songbirds tend to lay fewer eggs in each clutch than birds nesting at higher latitudes. David Lack of Oxford University first placed this observation in a life-history context. To what relation did Lack attribute this pattern?

Accepted Answer

Lack recognized that life-history traits

Question 8

Topic: the effects of resources
Difficulty: medium
Research on frogs has shown that compared with well-nourished counterparts, poorly nourished frogs mature

Accepted Answer

A)  at the same size but at a much later age. 
B)  at the same age but at a much smaller size. 
C)  at a somewhat later age and at a somewhat smaller size. 
D)  at a somewhat earlier age and at a somewhat smaller size. 
A)  at the same size but at a much later age. 
B)  at the same age but at a much smaller size. 
C)  at a somewhat later age and at a somewhat smaller size. 
D)  at a somewhat earlier age and at a somewhat smaller size.

Question 9

Explain why life history variables, such as number of offspring, size of offspring, and degree of parental care, are often correlated.

Accepted Answer

Species cannot maximize all of these tra

Question 10

The principle of allocation states that life history traits are adapted to maximize

Accepted Answer

A)  fitness. 
B)  frequency of reproduction. 
C)  number of offspring in the population. 
D)  ability of offspring to start populations in new habitats. 
E)  fecundity. 
A)  fitness. 
B)  frequency of reproduction. 
C)  number of offspring in the population. 
D)  ability of offspring to start populations in new habitats. 
E)  fecundity.

Question 11

-The data in the figure show a relationship between the mean flowering date for many plant species around Concord, New Hampshire, in the United States, and the mean spring temperature over a time span exceeding 150 years. However, there is a lot of scatter around the best-fit line in panel
b. What information in the chapter might suggest the source of this scatter, and what does it imply about the plant species' cues for flowering?

Accepted Answer

The scatter in the data could be due to

Question 12

Which of the following does NOT apply to indeterminate growth?

Accepted Answer

A)  growth in body size throughout life 
B)  cessation of growth upon maturation (adulthood) 
C)  flexible age of maturation 
D)  characteristic of plants and insects 
E)  semelparity 
A)  growth in body size throughout life 
B)  cessation of growth upon maturation (adulthood) 
C)  flexible age of maturation 
D)  characteristic of plants and insects 
E)  semelparity

Question 13

Explain two significant ways in which environmental productivity and stability can influence the number of offspring produced and their probability of survival.

Accepted Answer

A productive and stable environment will

Question 14

Is senescence inevitable? Please explain your answer, accounting for the great variation in patterns of aging among different species.

Accepted Answer

Yes, it appears that all mechanisms, bio

Question 15

Which life history type, fast or slow, is more likely to describe an endangered animal species?

Accepted Answer

Most endangered species probably have a

Question 16

Which life history type do mammals exhibit?

Accepted Answer

A)  slow 
B)  delayed 
C)  fast 
D)  accelerated 
A)  slow 
B)  delayed 
C)  fast 
D)  accelerated

Question 17

Fecundity is

Accepted Answer

A)  the number of reproductive episodes of an organism. 
B)  the amount of overall energy expended to reproduction over the life of an organism. 
C)  the number of offspring produced by an organism per reproductive episode. 
D)  the period in the life of an organism when it can produce offspring. 
A)  the number of reproductive episodes of an organism. 
B)  the amount of overall energy expended to reproduction over the life of an organism. 
C)  the number of offspring produced by an organism per reproductive episode. 
D)  the period in the life of an organism when it can produce offspring.

Question 18

Use this figure to answer questions 21 to 23.
  
-Which panel best illustrates the most direct effect of predation?

Accepted Answer

A)  a 
B)  b 
C)  c 
D)  d 
A)  a 
B)  b 
C)  c 
D)  d

Question 19

Some marine snails (species L) produce large numbers of small eggs that are shed into the sea, hatch at an early stage of development, and feed on microscopic plants. Other marine snails (species S) produce few eggs that are retained for a long time within the body of the mother snail in a brood pouch, hatch at an advanced stage of development, and immediately begin to feed on the surfaces of large plants like the adults. A biologist discovers approximately equal numbers of adults of species L and S in the same area over many generations. While studying the two species of snails, the biologist hypothesizes that the two species expend approximately the same amount of energy producing young. What assumption is the biologist making?

Accepted Answer

A)  Species S snails could produce as many eggs as species L snails under certain conditions. 
B)  An egg of species S contains more energy than an egg of species L. 
C)  Since species L snails produce more eggs, these eggs probably contain more energy. 
D)  Species S snails provide some energy to the young when they are in the brood pouch. 
A)  Species S snails could produce as many eggs as species L snails under certain conditions. 
B)  An egg of species S contains more energy than an egg of species L. 
C)  Since species L snails produce more eggs, these eggs probably contain more energy. 
D)  Species S snails provide some energy to the young when they are in the brood pouch.

Question 20

One might suppose that an earlier, longer summer would be beneficial for most species, because it offers a longer growing season for offspring. How might earlier offspring births in a predator species be detrimental to it?

Accepted Answer

If the prey species of the pre

How might population density affect life history?

Examine the equation for the coefficient of determination (), especially the total sums of squares. If we hold the error sums of squares constant, will the slope of the relation influence the value? Why or why not?

Which does NOT have slow life history attributes?

Use this figure to answer questions 27 and 28. -According to the figure, what are the implications of producing five versus eight eggs? Which option should be favoured by natural selection?

Tropical songbirds tend to lay fewer eggs in each clutch than birds nesting at higher latitudes. David Lack of Oxford University first placed this observation in a life-history context. To what relation did Lack attribute this pattern?

Topic: the effects of resources Difficulty: medium Research on frogs has shown that compared with well-nourished counterparts, poorly nourished frogs mature

Explain why life history variables, such as number of offspring, size of offspring, and degree of parental care, are often correlated.

The principle of allocation states that life history traits are adapted to maximize

Which of the following does NOT apply to indeterminate growth?

Explain two significant ways in which environmental productivity and stability can influence the number of offspring produced and their probability of survival.

Is senescence inevitable? Please explain your answer, accounting for the great variation in patterns of aging among different species.

Which life history type, fast or slow, is more likely to describe an endangered animal species?

Which life history type do mammals exhibit?

Fecundity is

Use this figure to answer questions 21 to 23. -Which panel best illustrates the most direct effect of predation?

One might suppose that an earlier, longer summer would be beneficial for most species, because it offers a longer growing season for offspring. How might earlier offspring births in a predator species be detrimental to it?

Introduction: Ecology, Evolution, and the Scientific Method

Adaptations to Aquatic Environments

Adaptations to Terrestrial Environments

Adaptations to Variable Environments

Climates and Soils

Terrestrial and Aquatic Biomes

Evolution and Adaptation

Reproductive Strategies

Social Behaviours

Population Distributions

Population Growth and Regulation

Population Dynamics Over Space and Time

Predation and Herbivory

Parasitism and Infectious Diseases

Competition

Community Structure

Community Succession

Movement of Energy in Ecosystems

Movement of Elements in Ecosystems

Landscape Ecology, Biogeography, and Global Biodiversity

Global Conservation of Biodiversity

Filters

Exam 8: Life Histories

How might population density affect life history?

Examine the equation for the coefficient of determination (), especially the total sums of squares. If we hold the error sums of squares constant, will the slope of the relation influence the value? Why or why not?

Which does NOT have slow life history attributes?

Use this figure to answer questions 27 and 28. -According to the figure, what are the implications of producing five versus eight eggs? Which option should be favoured by natural selection?

Tropical songbirds tend to lay fewer eggs in each clutch than birds nesting at higher latitudes. David Lack of Oxford University first placed this observation in a life-history context. To what relation did Lack attribute this pattern?

Topic: the effects of resources Difficulty: medium Research on frogs has shown that compared with well-nourished counterparts, poorly nourished frogs mature

Explain why life history variables, such as number of offspring, size of offspring, and degree of parental care, are often correlated.

The principle of allocation states that life history traits are adapted to maximize

Which of the following does NOT apply to indeterminate growth?

Explain two significant ways in which environmental productivity and stability can influence the number of offspring produced and their probability of survival.

Is senescence inevitable? Please explain your answer, accounting for the great variation in patterns of aging among different species.

Which life history type, fast or slow, is more likely to describe an endangered animal species?

Which life history type do mammals exhibit?

Fecundity is

Use this figure to answer questions 21 to 23. -Which panel best illustrates the most direct effect of predation?

One might suppose that an earlier, longer summer would be beneficial for most species, because it offers a longer growing season for offspring. How might earlier offspring births in a predator species be detrimental to it?

Introduction: Ecology, Evolution, and the Scientific Method

Adaptations to Aquatic Environments

Adaptations to Terrestrial Environments

Adaptations to Variable Environments

Climates and Soils

Terrestrial and Aquatic Biomes

Evolution and Adaptation

Reproductive Strategies

Social Behaviours

Population Distributions

Population Growth and Regulation

Population Dynamics Over Space and Time

Predation and Herbivory

Parasitism and Infectious Diseases

Competition

Community Structure

Community Succession

Movement of Energy in Ecosystems

Movement of Elements in Ecosystems

Landscape Ecology, Biogeography, and Global Biodiversity

Global Conservation of Biodiversity

Filters