Deck 12: Life Histories

Question 1

Which statement about the impact of dams on cottonwood forests is false?

A) Damming reduces growth of established cottonwoods downstream.
B) Damming increases mortality of established cottonwoods downstream.
C) By reducing flooding downstream, damming improves cottonwood seed germination.
D) The timing of water release from a dam can greatly affect cottonwood seed germination.
E) Careful management of flow through dams can greatly reduce harmful impacts on cottonwoods downstream.

Answer 1

C

Question 2

A fish maturing late with large body size and producing many small offspring would be said to have a(n)

A) periodic life history.
B) opportunistic life history.
C) equilibrium life history.
D) precocial life history.
E) stress-tolerant life history.

Answer 2

A

Question 3

Because natural selection has shaped fish life histories,

A) fish species with high adult mortality tend to mature at a younger age.
B) fish species with high adult mortality tend to mature at an older age.
C) fish species with high adult mortality tend to invest relatively large amounts of energy in reproduction.
D) 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.
E) Both fish species with high adult mortality tend to mature at an older age and fish species with high adult mortality tend to invest relatively large amounts of energy in reproduction are true.

Answer 3

D

Question 4

The study of the relationship between climate and the timing of ecological events is called

A) ecology.
B) phenology.
C) oenology.
D) climatology.
E) life history theory.

Question 5

As a fraction of adult mass,the mass of offspring at independence tends to be largest in

A) mammals.
B) altricial birds.
C) lizards.
D) both mammals and lizards.
E) All three groups have similar values.

Question 6

The principle of allocation states

A) if an organism uses energy for one function it reduces the amount of energy available for other functions.
B) organisms have a tendency to select the smallest prey available rather than exert more energy in capturing larger prey.
C) organisms that build larger nests produce fewer offspring.
D) organisms have a tendency to allocate more time and energy to a single preferred offspring while neglecting others.
E) plants allocate their energy such that larger seedlings come from smaller seeds.

Question 7

The number of eggs laid by a female is called her

A) fertility.
B) gonadosomatic index.
C) growth form.
D) rotundity.
E) fecundity.

Question 8

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?

A) nutrient limitation
B) competition from established plants
C) shade
D) deep burial in soil
E) disturbance

Question 9

A polymorphic locus is one that

A) codes for more than one protein.
B) codes for both protein and lipid.
C) occurs in a population as more than one allele.
D) occurs on more than one chromosome.
E) can cause more than one phenotype in an individual, depending on the environment.

Question 10

Which of the following is NOT a characteristic favored by K-selection?

A) low intrinsic rate of increase
B) late reproduction
C) many, small offspring
D) repeated bouts of reproduction
E) strong competitive ability

Question 11

Which of the following is NOT true of riparian plant communities?

A) plant species adapted to frequent disturbance by flooding
B) plant species dependent on flooding often dominant
C) low species diversity, compared to surrounding terrestrial communities
D) high population densities, compared to surrounding terrestrial communities
E) seriously impacted by human activities

Question 12

A "forb" is a(n)

A) fish species living in the open ocean.
B) bird species having offspring independent at a young age.
C) plant species with woody tissue.
D) grass or sedge.
E) herbaceous, but non-graminoid, plant species.

Question 13

The "K" in "K-selection" comes from the

A) ecologist who coined it, Astrid Kodric-Brown.
B) shape of the age-vs.-mortality-rate plot for K-selected species.
C) "K" in the logistic growth equation.
D) Greek letter "kappa," symbolizing fecundity.
E) None of the choices are correct.

Question 14

Seeds bearing eliasomes are likely to be dispersed by

A) ants.
B) wind.
C) water.
D) birds.
E) scatterhoarding mammals.

Question 15

__________ show more variation in life history traits than any other group.

A) All of the choices show equal amounts of variation in life history traits.
B) Mammals
C) Birds
D) Reptiles
E) Fish

Question 16

Which of the following observations can be explained by the energetic limitation of an organism's total reproductive effort?

A) Darter diversity is very high in the Ozark Highlands.
B) Darters that lay many eggs lay smaller eggs, on average.
C) Seed size in plants varies over at least 10 orders of magnitude.
D) Seed size in plants depends in part on the plant's seed dispersal mechanism.
E) More than one of the choices.

Question 17

Grime's classification of plant life histories focuses attention on

A) stress and disturbance.
B) stress and nutrient availability.
C) disturbance and gene flow.
D) disturbance and plant species diversity.
E) r- vs. K-selection.

Question 18

Among fish species,an "opportunistic" life history is characterized by

A) high juvenile survival, large numbers of offspring, and early maturity.
B) high juvenile survival, large numbers of offspring, and late maturity.
C) low juvenile survival, low number of offspring, and early maturity.
D) traits that maximize colonizing ability for environments that do not vary much in time or space.
E) traits that maximize colonizing ability for environments that are very stressful.

Question 19

"Riparian" refers to plant communities occurring

A) in the tropics.
B) at high altitudes.
C) along the edges of deserts.
D) in permanently flooded areas.
E) in transitions between riverbanks and upland areas.

Question 20

In Grime's classification,stress-tolerant plants

A) live under conditions of high stress and also high disturbance.
B) grow rapidly.
C) are very palatable to herbivores.
D) conserve nutrients and water.
E) All of the choices are correct.

Question 21

Turner and Trexler found a __________ relationship between egg size and ________ in the darter populations that live in rivers and streams of central North America.

A) positive; gene flow
B) positive; egg number
C) positive; female size
D) positive; clutch size
E) negative; gene flow

Question 22

Bird species whose offspring are born helpless and depending on parental care are said to be _____________.

Question 23

Which of the following are characteristics favored by K selection?

A) iteroparity
B) small body size
C) rapid development
D) high r_max
E) early reproduction

Question 24

Which of the following influence the number and size of seeds produced by plants?

A) growth form
B) dispersal mode
C) disturbance intensity
D) All of the choices are correct.
E) both growth form and dispersal mode

Question 25

Westoby,Leishman,and Lord found that on average,________ produce the largest seeds.

A) forbs
B) woody plants
C) climbing plants and vines
D) graminoids
E) herbs

Question 26

In Grime's classification,a plant species adapted to highly disturbed environments is called a ____________ species.

Question 27

Rates of gene flow can be estimated from similarity in allele frequencies among populations.

Question 28

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?

A) vertebrate-dispersed, ant-dispersed, scatterhoarded, wind-dispersed
B) unassisted, ant-dispersed, scatterhoarded, wind-dispersed
C) scatterhoarded, vertebrate-dispersed, ant-dispersed, adhesion-adapted
D) unassisted, adhesion-adapted, ant-dispersed, scatterhoarded
E) unassisted, adhesion-adapted, wind-dispersed, ant-dispersed

Question 29

Life histories typical of r-selection are most likely to evolve where species populations are near carrying capacity much of the time.