Behavioural Ecology and Conservation Biology

Question 1

The evolution of mating systems is most likely affected by

a) territoriality
b) certainty of paternity
c) population density
d) sexual dimorphism
e) None of the options are correct

Answer 1

d) sexual dimorphism

Question 2

The colour of throats of males in a population of side-blotched lizards is determined by

a) their receptiveness to mate
b) stage of development/maturity
c) the success of the mating behaviour of each of the throat colour phenotypes
d) ambient temperature - blue = cold; orange = normal; yellow = hot
e) the frequency of homozygous recessive genotype

Answer 2

c) the success of the mating behaviour of each of the throat colour phenotypes

Question 3

In guppies, females may copy the mate choice of conspecifics even if it means choosing a male with less extensive orange colouration than would be chosen with no female present. This decision may increase

a) ornamentation of offspring
b) the number of resulting offspring
c) male competition for mates
d) paternal care of offspring
e) the probability of fitness of male offspring

Answer 3

e) the probability of fitness of male offspring

Question 4

The mating system in which females are more ornamented than males is

a) monogamy
b) polygyny
c) Polyandry
d) promiscuity
e) polygamy

Answer 4

c) polyandry

Question 5

Which of the following is not a display of altruistic behaviour?

a) Richardson’s ground squirrel emitting an alarm call to unaware neighbours
b) green lacewing producing a hybrid courtship song
c) worker honeybee stinging an intruder and subsequently dying
d) vervet monkey alarm calling when spotting an eagle
e) non-reproductive naked mole rat protecting the queen from predation

Answer 5

b) green lacewing producing a hybrid courtship song

Question 6

According to the small-population approach, what would be the best strategy for saving a population that is in an extinction vortex?

a) determining the minimum viable population size by taking into account the effective population size
b) reducing the population size of its predators and competitors
c) introducing individuals from other populations to increase genetic variation
d) determining and remedying the cause of its decline
e) establishing a nature reserve to protect its habitat

Answer 6

c) introducing individuals from other populations to increase genetic variation

Question 7

Of the following ecosystem types, which have been impacted the most by humans?

a) desert and high alpine
b) open and benthic ocean
c) tundra and arctic
d) wetland and riparian
e) taiga and second-growth forests

Answer 7

d) wetland and riparian

Question 8

What term did E. O. Wilson coin for our innate appreciation of wild environments and living organisms?

a) biophilia
b) bioethics
c) biophobia
d) biremediation
e) landscape ecology

Answer 8

a) biophilia

Question 9

Small populations are most vulnerable to ________ and ________.

a) loss of variation, small mate choice
b) genetic drift, heterozygosity
c) loss of adaptability, heterozygosity
d) inbreeding, genetic drift
e) inbreeding, disease

Answer 9

d) inbreeding and genetic drift

Question 10

Which of the following provides the best evidence of a biodiversity crisis?

a) climate change
b) decrease in regional productivity
c) high rate of extinction
d) the incursion of a non-native species
e) increasing pollution levels

Answer 10

c) high rate of extinction

Question 11

Which of the following statements is consistent with the principle of competitive exclusion?

a) Natural selection tends to increase competition between related species
b) Bird species generally do not compete for nesting sites
c) Two species with the same fundamental niche will exclude other competing species
d) The random distribution of one competing species will have a positive impact on the population growth of the other competing species.
e) Even a slight reproductive advantage will eventually lead to the elimination of the less well-adapted of two competing species.

Answer 11

e) Even a slight reproductive advantage will eventually lead to the elimination of the less well-adapted of two competing species.

Question 12

Why do tropical communities tend to have greater species diversity than temperate or polar communities?

a) There are fewer parasites to negatively affect the health of tropical communities.
b) Tropical communities are generally older than temperate and polar communities.
c) Tropical communities are low in altitude, whereas temperate and polar communities are high in altitude.
d) More competitive dominant species have evolved in temperate and polar communities.
e) They are less likely to be affected by human disturbance.

Answer 12

b) Tropical communities are generally older than temperate and polar communities.

Question 13

Which of the following is an example of an ecosystem?

a) a pond and all of the plant and animal species that live in it
b) interactions between all of the organisms and their physical environment in a tropical rain forest
c) the intricate interactions of the various plant and animal species on a savanna during a drought
d) all of the brook trout in a 500 hectare2 river drainage system
e) the plants, animals, and decomposers that inhabit an alpine meadow

Answer 13

b) interactions between all of the organisms and their physical environment in a tropical rain forest

Question 14

Why does a vegetarian leave a smaller ecological footprint than an omnivore?

a) Eating meat is an inefficient way of acquiring photosynthetic productivity.
b) There is an excess of plant biomass in all terrestrial ecosystems.
c) Vegetarians require less protein than do omnivores.
d) Fewer animals are slaughtered for human consumption.
e) Vegetarians need to ingest less chemical energy than omnivores.

Answer 14

a) Eating meat is an inefficient way of acquiring photosynthetic productivity

Question 15

The growing season would generally be shortest in which of the following biomes?

a) tropical rain forest
b) savanna
c) temperate broadleaf forest
d) coniferous forest
e) temperate grassland

Answer 15

d) coniferous forest

Question 16

If you are interested in observing a relatively simple community structure in a clear water lake, you would do well to choose diving into

a) an oligotrophic lake
b) a lake with consistently warm temperatures
c) a relatively shallow lake
d) a nutrient-rich lake
e) a eutrophic lake

Answer 16

a) an oligotrophic lake

Question 17

A population of ground squirrels has an annual per capita birth rate of 0.06 and an annual per capita death rate of 0.02. Calculate an estimate of the number of individuals added to (or lost from) a population of 1000 individuals in one year.

a) 20 individuals added
b) 120 individuals added
c) 400 individuals added
d) 20 individuals lost
e) 40 individuals added

Answer 17

e) 40 individuals added

Question 18

Which of the following is not an example of density-dependent regulation?

a) a severe frost
b) territoriality
c) competition and predation
d) disease
e) intrinsic physiological factors

Answer 18

a) a severe frost

Question 19

In the evolution of whelk-eating behaviour in crows, which of the following was optimized through natural selection?

a) the average total energy used to break shells
b) the average number of drops required to break the shell
c) the average thickness of the shells dropped by the birds
d) the average height a bird flew to drop a shell
e) the average size of the shells dropped by the birds

Answer 19

a) the average total energy used to break shells

Question 20

The presence of altruistic behaviour is most likely due to kin selection, a theory maintaining that

a) critical thinking abilities are normal traits for animals and they have arisen, like other traits, through natural selection.
b) natural selection has generally favoured the evolution of exaggerated aggressive and submissive behaviours to resolve conflict without grave harm to participants.
c) companionship is advantageous to animals because in the future they can help each other.
d) genes enhance survival of copies of themselves by directing organisms to assist others who share those genes.
e) aggression between sexes promotes the survival of the fittest individuals.

Answer 20

d) genes enhance survival of copies of themselves by directing organisms to assist others who share those genes.

Question 21

Imagine that you are designing an experiment aimed at determining whether the initiation of migratory behaviour is largely under genetic control. Of the following options, the best way to proceed is to

a) perform within-population matings with birds from different populations that have different migratory habits. Rear the offspring in the absence of their parents and observe the migratory behaviour of offspring.
b) observe genetically distinct populations in the field and see if they have different migratory habits.
c) perform within-population matings with birds from different populations that have different migratory habits. Do this in the laboratory and see if offspring display parental migratory behaviour.
d) bring animals into the laboratory and determine the conditions under which they become restless and attempt to migrate.
e) All of the options are equally productive ways to approach the question.

Answer 21

a) perform within-population matings with birds from different populations that have different migratory habits. Rear the offspring in the absence of their parents and observe the migratory behaviour of offspring.

Question 22

Which of the following statements is true about certainty of paternity?

a) Males that guard females they have mated with are certain of their paternity.
b) Certainty of paternity is high in most species with internal fertilization because the acts of mating and birth are separated by time.
c) Paternal behaviour exists because it has been reinforced over generations by natural selection.
d) Young or eggs laid by a female are likely to contain the same genes as another female’s eggs in a population of birds.
e) Certainty of paternity is low when egg laying and mating occur together, as in external fertilization.

Answer 22

c) Paternal behaviour exists because it has been reinforced over generations by natural selection.

Question 23

Which of the following best describes “game theory” as it applies to animal behaviour?

a) The total of all of the behavioural displays, both male and female, is related to courtship.
b) The evolutionary “game” is played between predator and prey, wherein the prey develops a behaviour through natural selection that enables it to be less vulnerable to predation, and the predator counters with a new reciprocal predatory behaviour.
c) The fitness of a particular behaviour is influenced by other behavioural phenotypes in a population.
d) An individual in a population changes a behavioural phenotype to gain a competitive advantage.
e) The play behaviour performed by juveniles allows them to perfect adult behaviours that are needed for survival, such as hunting, courtship, and so on.

Answer 23

c) The fitness of a particular behaviour is influenced by other behavioural phenotypes in a population.

Question 24

Which of the following examples poses the greatest potential threat to biodiversity?

a) trapping and relocating large predators, such as mountain lions, that pose a threat as they move into areas of relatively dense human populations
b) allowing previously used farmland to go fallow and begin to fill in with weeds and then shrubs and saplings
c) releasing sterilized rainbow trout to boost the sport fishing of a river system that contains native brook trout
d) importing an Asian insect into the United States to control a weed that competes with staple crops
e) replanting, after a clear cut, a monoculture of Douglas fir trees on land that consisted of old-growth Douglas fir, western cedar, and western hemlock

Answer 24

d) importing an Asian insect into the United States to control a weed that competes with staple crops

Question 25

According to the U.S. Endangered Species Act (ESA), the difference between an endangered species and a threatened one is that

a) only endangered species are vertebrates.
b) threatened species are endangered species outside the U.S. borders.
c) a threatened species is closer to extinction.
d) endangered species are mainly tropical.
e) an endangered species is closer to extinction.

Answer 25

e) an endangered species is closer to extinction.

Question 26

Which of the following is a type of research in which a conservation biologist would be involved?

a) determining the effects of hunting white-tailed deer in Vermont
b) studying species diversity and interaction in the Florida Everglades, past and present
c) studying population ecology of grizzly bears in Yellowstone National Park
d) determining the effect of protection programs on the recovery of the North Atlantic cod fishery
e) reestablishing whooping cranes in their former breeding grounds in North Dakota

Answer 26

e) reestablishing whooping cranes in their former breeding grounds in North Dakota

Question 27

Review the formula for effective population size. Imagine a population of 1000 small rodents. Of these, 300 are breeding females, 300 are breeding males, and 400 are nonbreeding juveniles. What is the effective population size?

a) 1200
b) 300
c) 1000
d) 400
e) 600

Answer 27

e) 600

Question 28

To better comprehend the magnitude of current extinctions, it will be necessary to

a) focus on identifying more species of mammals and birds.
b) identify more of the yet unknown species of organisms on Earth.
c) use the average extinction rates of vertebrates as a baseline.
d) monitor atmospheric carbon dioxide levels more closely.
e) differentiate between plant extinction and animal extinction numbers.

Answer 28

b) identify more of the yet unknown species of organisms on Earth.

Question 29

An event that changes resource availability and removes individuals from a community is a

Answer 29

disturbance

Question 30

Which of the following would be most significant in understanding the structure of an ecological community?

a) determining the kinds of interactions that occur among organisms of different species
b) determining how many species are present overall
c) determining how many species are present overall, which particular species are present, the kinds of interactions that occur among organisms of different species, and the relative abundance of species
d) determining the relative abundance of species
e) determining which particular species are present

Answer 30

c) determining how many species are present overall, which particular species are present, the kinds of interactions that occur among organisms of different species, and the relative abundance of species

Question 31

Trophic efficiency is

a) the percentage of production transferred from one trophic level to the next.
b) about 90% in most ecosystems.
c) a measure of how nutrients are cycled from one trophic level to the next.
d) usually greater than production efficiencies.
e) the ratio of net secondary production to assimilation of primary production.

Answer 31

a) the percentage of production transferred from one trophic level to the next.

Question 32

The rate at which nutrients move through an ecosystem is most often limited by

a) density of primary consumers.
b) decomposition rate.
c) density of tertiary consumers.
d) primary production.
e) density of secondary consumers.

Answer 32

b) decomposition rate

Question 33

A rain shadow is

a) the windward side of the mountain that receives much of rain.
b) the windward side of the mountain that receives little rain.
c) the leeward side of the mountain that receives dry air.
d) the region close to shore sheltered by the mountains.
e) regions near 30 degrees N and 30 degrees S latitude that have dry air.

Answer 33

c) the leeward side of the mountain that receives dry air

Question 34

Population ecologists are primarily interested in

a) how humans affect the size of wild populations of organisms.
b) understanding how biotic and abiotic factors influence the density, distribution, size, and age structure of populations.
c) the overall vitality of a population of organisms.
d) how populations evolve as natural selection acts on heritable variations among individuals and changes in gene frequency.
e) studying interactions among populations of organisms that inhabit the same area.

Answer 34

b) understanding how biotic and abiotic factors influence the density, distribution, size, and age structure of populations.

Question 35

Which of the following best defines a cohort?

a) a group of the individuals from the same age group, from birth until they are all dead
b) the number of individuals that annually die or emigrate out of a population
c) a group of individuals that inhabits a small isolated region within the range for the species
d) the reproductive males and females within the population
e) all of the individuals that are annually added to a population by birth and immigration

Answer 35

a) a group of the individuals from the same age group, from birth until they are all dead

Question 36

The central concept of sociobiology is that
a) the behaviour of an individual cannot be modified
b) the social behaviour of humans is homologous to the social behaviour of other social animals.
c) human behaviour is rigidly predetermined.
d) most aspects of our social behaviour have an evolutionary basis.
e) human behaviour consists mainly of fixed action patterns.

Answer 36

d) most aspects of our social behaviour have an evolutionary basis

Question 37

Two populations of the highly ornamented white-crested sparrow species are spatially separated by a mountain range. Males from the two populations exhibit differing elaborate courtship displays. When a female appears, the males from the eastern population approach the female while bobbing their heads and spreading their wings, while the western population approaches a female by hopping and flapping their wings. Individuals from each population reared in isolation exhibited the same courtship displays as those in the wild.

After mating a female from the eastern population to a male from the western population, the resulting male offspring exhibited a hybrid courtship display, bobbing their heads and flapping their wings. This indicates that

a) the elicited courtship display depends on female response.
b) courtship displays are a result of environmental pressures.
c) courtship displays are under the control of more than one gene.
d) associative learning is involved in courtship displays.
e) courtship displays are a learned behaviour.

Answer 37

c) courtship displays are under the control of more than one gene

Question 38

Feeding behaviour with a high energy intake-to-expenditure ratio is called

a) optimal foraging.
b) heterotrophy.
c) search scavenging.
d) autotrophy.
e) herbivory.

Answer 38

a) optimal foraging

Question 39

Which of the following statements about evolution of behaviour is correct?

a) Natural selection will favour behaviour that enhances survival and reproduction
b) Innate behaviours can never be altered by natural selection.
c) If a behaviour is less than optimal, it will eventually become optimal through natural selection.
d) An animal may show behaviour that minimizes reproductive fitness.
e) All of the statements are correct.

Answer 39

a

Question 40

Animals that help other animals of the same species

a) are bigger and stronger than the other animals.
b) are always male.
c) have excess energy reserves.
d) are usually related to the other animals.
e) have defective genes controlling their behaviour.

Answer 40

d) are usually related to the other animals.

Question 41

The primary difference between the small-population approach (S-PA) and the declining-population approach (D-PA) to biodiversity recovery is

a) S-PA is interested in bolstering the genetic diversity of a threatened population rather than the environmental factors that caused the population’s decline.
b) D-PA would use recently collected population data to calculate an extinction vortex.
c) S-PA kicks in for conservation biologists when population numbers fall below 500.
d) S-PA would investigate and eliminate all of the human impacts on the habitat of the species being studied for recovery.
e) D-PA would likely involve bringing together individuals from scattered small populations to interbreed in order to promote genetic diversity.

Answer 41

a) S-PA is interested in bolstering the genetic diversity of a threatened population rather than the environmental factors that caused the population’s decline.

Question 42

How might the extinction of some Pacific Island bats called “flying foxes” threaten the survival of over 75% of the tree species in those islands?

a) The bats pollinate the trees and disperse seeds
b) The bats roost in the trees and fertilize soil around the trees with their nitrogen-rich droppings.
c) The bats eat the insects that harm competitor plants.
d) The bats consume the fruit including the seeds that would disrupt the trees’ reproductive cycle.
e) The bats pierce the fruit, which allows the seeds to germinate.

Answer 42

a) The bats pollinate the trees and disperse seeds

Question 43

If the sex ratio in a population is significantly different from 50:50, then which of the following will always be true?

a) The effective population size will be less than the actual population size.
b) The genetic variation in the population will decrease over time.
c) The effective population size will be greater than the actual population size.
d) The population will enter the extinction vortex.
e) The genetic variation in the population will increase over time.

Answer 43

a) The effective population size will be less than the actual population size.

Question 44

Which of the following is the most direct threat to biodiversity?

a) habitat destruction
b) increased levels of atmospheric carbon dioxide
c) overexploitation of selected species
d) the depletion of the ozone layer
e) zoned reserves

Answer 44

a) habitat destruction

Question 45

Which of the following conditions is the most likely indicator of a population in an extinction vortex?

a) The population is no longer connected by corridors.
b) The species in question is found only in small pockets of its former range.
c) The effective population size of the species falls below 500.
d) The population is geographically divided into smaller populations.
e) Genetic measurements indicate a loss of genetic variation over time.

Answer 45

e) Genetic measurements indicate a loss of genetic variation over time.

Question 46

In a particular case of secondary succession, three species of wild grass all invaded a field. By the second season, a single species dominated the field. A possible factor in this secondary succession was

a) equilibrium.
b) parasitism.
c) facilitation.
d) immigration.
e) inhibition.

Answer 46

e) inhibition.

Question 47

The following statements about community structure and interactions are correct, with the exception of which one?

a) The trophic cascade model suggests that the lower trophic levels influence/control the higher trophic levels.
b) High-diversity communities are often more resilient to invasive species than low-diversity communities.
c) An organism that influences a community by changing its physical environment is referred to as an ecosystem engineer.
d) The dynamic stability hypothesis suggests that long food chains are less stable than low food chains.
e) Communities show variation in the top-down and bottom-down community control.

Answer 47

a

Question 48

A 3-hectare lake in the American Midwest suddenly has succumbed to an algal bloom. What is the likely cause of eutrophication in freshwater ecosystems, such as this one?

a) iron dust blowing into the lake
b) increased solar radiation
c) introduction of non-native tertiary consumer fish
d) accidental introduction of a prolific culture of algae
e) nutrient runoff

Answer 48

e) nutrient runoff

Question 49

Which of the following choices includes all of the others in creating global terrestrial climates?

a) ocean currents
b) Earth’s rotation on its axis
c) evaporation of water from ocean surfaces
d) differential heating of earth’s surface
e) global wind patterns

Answer 49

d) differential heating of earth’s surface

Question 50

What is the limiting factor for the growth of trees in the tundra?

Answer 50

permafrost

Question 51

In Belding’s ground squirrels, it is mostly the females that behave altruistically by sounding alarm calls. What is the likely reason for this distinction?

a) Males have smaller vocal cords and are less likely to make sounds.
b) Females invest more in foraging and food stores, so they are more defensive.
c) Males forage in areas separate from females; therefore, alarm calls are useless.
d) Females settle in the area in which they were born, so the alarm is warning kin.
e) The sex ratio is biased.

Answer 51

Females settle in the area in which they were born, so the alarm is warning kin

Question 52

How do altruistic behaviours arise through natural selection?

a) Animals that perform altruistic acts are allowed by their population to breed more, thereby passing on their behaviour genes to future generations.
b) By his/her actions, the altruist increases the likelihood that some of its genes will be passed on to the next generation.
c) Altruistic behaviours lower stress in populations, which increases the survivability of all the members of the population.
d) The altruist is appreciated by other members of the population because their survivability has been enhanced by virtue of his/her risky behaviour.
e) All of the options are correct.

Answer 52

b) By his/her actions, the altruist increases the likelihood that some of its genes will be passed on to the next generation

Question 53

In guppies, females may copy the mate choice of conspecifics even if it means choosing a male with less extensive orange colouration than would be chosen with no female present. This decision may increase

a) ornamentation of offspring.
b) the number of resulting offspring.
c) male competition for mates.
d) paternal care of offspring.
e) the probability of fitness of male offspring.

Answer 53

the probability of fitness of male offspring

Question 54

The colour of throats of males in a population of side-blotched lizards is determined by

a) their receptiveness to mate.
b) stage of development/maturity.
c) the success of the mating behaviour of each of the throat colour phenotypes.
d) ambient temperature—blue = cold; orange = normal; yellow = hot.
e) the frequency of homozygous recessive genotype.

Answer 54

c) the success of the mating behaviour of each of the throat colour pheotypes

Question 55

In the evolution of whelk-eating behaviour in crows, which of the following was optimized through natural selection?

the average total energy used to break shells
the average number of drops required to break the shell
the average thickness of the shells dropped by the birds
the average height a bird flew to drop a shell
the average size of the shells dropped by the birds

Answer 55

the average total energy used to break shells

Question 56

Extinction is a natural phenomenon. It is estimated that 99% of all species that ever lived are now extinct. Why then do we say that we are now experiencing an extinction (loss of biodiversity) crisis?

Answer 56

The current rate of extinction is high and human activities threaten biodiversity at all levels

Question 57

According to the small-population approach, what would be the best strategy for saving a population that is in an extinction vortex?

determining the minimum viable population size by taking into account the effective population size
reducing the population size of its predators and competitors
introducing individuals from other populations to increase genetic variation
determining and remedying the cause of its decline
establishing a nature reserve to protect its habitat

Answer 57

introducing individuals from other populations to increase genetic variation

Question 58

The most serious consequence of a decrease in global biodiversity would be the

a) loss of species for “bioprospecting”
b) increase in the abundance and diversity of edge-adapted species
c) increase in global warming and thinning of the ozone layer
d) potential loss of ecosystem services on which people depend
e) loss of source of genetic diversity to preserve endangered species

Answer 58

potential loss of ecosystem services on which people depend

Question 59

Some populations of sea turtles and Galapagos tortoises are maintained by people who collect their eggs and hatch/rear the young in captivity. Why is this practice supported by conservationists?

This is a good way to census the wild populations.
You want to prevent both species from over-reproducing.
The eggs are given only to people who need high protein.
It is an inexpensive way to raise young turtles and tortoises for food.
Introduced species can be effective predators and consume all or most of the eggs that are laid.

Answer 59

introduced species can be effective predators and consume all or most of the eggs that are laid

Question 60

small populations are most vulnerable to ___ and ___

Answer 60

inbreeding, genetic drift

Question 61

How might an ecologist test whether a species is occupying its realized or its fundamental niche?

a) Observe if the niche size changes after the addition of nutritional resources to the habitat.
b) Remove a competitor species to see if the species expands its range.
c) Study the temperature range and humidity requirements of the species.
d) Observe if the niche size changes after the introduction of a similar non-native species.
e) Measure the change in reproductive success when the species is subjected to environmental stress.

Answer 61

b) remove a competitor species to see if the species expands its range

Question 62

In a tide pool, 15 species of invertebrates were reduced to eight after one species was removed. The species removed was likely a(n)

mutualistic organism.
resource partitioner.
pathogen.
keystone species.
herbivore.

Answer 62

keystone species

Question 63

Nitrogen is available to plants only in the form of

a) nitrate ions in the soil
b) amino acids from decomposing plant and animal proteins
c) uric acid from animal excretions
d) N2 in the atmosphere
e) nitrite ions in the soil

Answer 63

a) nitrate ions in the soil

Question 64

Subtraction of which of the following will convert gross primary productivity into net primary productivity?

the energy used by autotrophs in respiration
the energy contained in the standing crop
the energy fixed by photosynthesis
the energy used by heterotrophs in respiration
all solar energy

Answer 64

the energy used by autotrophs in respiration

Question 65

Which of the following abiotic factors has the greatest influence on the metabolic rates of plants and animals?

a) temperature
b) wind
c) disturbances
d) water
e) rocks and soil

Answer 65

temperature

Question 66

Generally speaking, deserts are located in places where air masses are usually

tropical
expanding
rising
descending
humid

Answer 66

descending

Question 67

Which of the following is the best example of uniform distribution?

snails in an intertidal zone at low tide
a cultivated cornfield in the Midwest
mushrooms growing on the floor of an old growth forest
bees collecting pollen in a wildflower meadow
territorial songbirds in a mature forest during mating season

Answer 67

territorial songbirds in a mature forest during mating season

Question 68

Which of the following might affect the foraging behaviour of an animal in the context of optimal foraging?

a) prey density
b) prey size
c) risk of predation
d) prey defences
e) all of the options are correct

Answer 68

e

Question 69

The evolution of mating systems is most likely affected by

a) territoriality
b) certainty of paternity
c) population density
d) sexual dimorphism
e) None of the options is correct

Answer 69

d) sexual dimorphism

Question 70

The mating system in which females are more ornamented than males is

a) monogamy
b) polygyny
c) polyandry
d) promiscuity
e) polygamy

Answer 70

c) polyandry

Question 71

Which of the following does not have a coefficient of relatedness of 0.5?

a) mother to her son
b) father to his daughter
c) a brother to his brother
d) an uncle to his nephew
e) a sister to her brother

Answer 71

an uncle to his nephew

Question 72

You discover a rare new bird species, but you are unable to observe its mating behaviour. You see that the male is large and ornamental compared with the female. On this basis, you can probably conclude that the species is

a) monogamous
b) agonistic
c) promiscuous
d) polygamous
e) polyandrous

Answer 72

d) polygamous

Question 73

Which of the following groups is most threatened by global extinctions?

a) amphibians
b) mammals
c) birds
d) plants
e) fish

Answer 73

a) amphibians

Question 74

How might the extinction of some Pacific Island bats called “flying foxes” threaten the survival of over 75% of the tree species in those islands?

a) The bats pollinate the trees and disperse seeds.
b) The bats roost in the trees and fertilize soil around the trees with their nitrogen-rich droppings.
c) The bats eat the insects that harm competitor plants.
d) The bats consume the fruit including the seeds that would disrupt the trees’ reproductive cycle.
e) The bats pierce the fruit, which allows the seeds to germinate.

Answer 74

a

Question 75

According to the U.S. Endangered Species Act (ESA), the difference between an endangered species and a threatened one is that

Answer 75

an endangered species is closer to extinction

Question 76

Of the following ecosystem types, which have been impacted the most by humans?

a) desert and high alpine
b) open and benthic ocean
c) tundra and arctic
d) wetland and riparian
e) taiga and second-growth forests

Answer 76

d) wetland and riparian

Question 77

Extinction is a natural phenomenon. It is estimated that 99% of all species that ever lived are now extinct. Why then do we say that we are now experiencing an extinction (loss of biodiversity) crisis?

a) The current rate of extinction is high and human activities threaten biodiversity at all levels.
b) Most biodiversity hot spots have been destroyed by recent ecological disasters.
c) Humans are ethically responsible for protecting endangered species.
d) Humans have greater medical needs than at any other time in history, and many potential medicinal compounds are being lost as plant species become extinct.
e) Scientists have finally identified most of the species on Earth and are thus able to quantify the number of species becoming extinct.

Answer 77

a) The current rate of extinction is high and human activities threaten biodiversity at all levels.

Question 78

There are more species in tropical areas than in places more distant from the equator. This is probably a result of

a) more intense annual solar radiation
b) more frequent ecological disturbances
c) fewer agents of disease
d) fewer predators, more intense annual solar radiation, more frequent ecological disturbances, and fewer agents of disease.
e) fewer predators

Answer 78

a

Question 79

Which of the following is true of detrivores?

a) They synthesize organic molecules that are used by primary producers.
b) Some species are autotrophic, while others are heterotrophic.
c) They secrete enzymes that convert the organic molecules of detritus into CO2 and H2O.
d) They recycle chemical elements directly back to primary consumers.
e) They convert organic materials from all trophic levels to inorganic compounds usable by primary producers.

Answer 79

d) They recycle chemical elements directly back to primary consumers.

Question 80

Which of the following is an example of a local biogeochemical cycle?

a) O2 released by oak trees in a forest
b) excess NO3- converted to N2 by denitrifying soil bacteria
c) CO2 absorbed by phytoplankton in the open ocean
d) organic carbon remains of a leaf being converted to CO2 by a fungus
e) phosphorous being absorbed from the soil by a corn plant

Answer 80

e) phosphorous being absorbed from the soil by a corn plant

Question 81

Species introduced by humans to new geographic locations

Answer 81

can outcompete and displace native species for biotic and abiotic resources.

Question 82

Generalized global air circulation and precipitation patterns are caused by

polar, cool, moist high-pressure air masses from the poles that move along the surface, releasing precipitation along the way to the equator where they are heated and dried.

rising, warm, moist air masses that cool and release precipitation as they rise and then, at high altitude, cool and sink back to the surface as dry air masses after moving north or south of the tropics.

mountain ranges that deflect air masses containing variable amounts of moisture.

the revolution of Earth around the sun.

air masses that are dried and heated over continental areas that rise, cool aloft, and descend over oceanic areas followed by a return flow of moist air from ocean to land, delivering high amounts of precipitation to coastal areas.

Answer 82

rising, warm, moist air masses that cool and release precipitation as they rise and then, at high altitude, cool and sink back to the surface as dry air masses after moving north or south of the tropics.

Question 83

Which of the following choices would most likely promote random distribution?

a) territorial species
homogeneous chemical and physical factors in the environment
species that secrete chemicals to attract or inhibit other individuals
spacing during the breeding season
flocking and schooling behaviours

Answer 83

b) homogeneous chemical and physical factors in the environment

Question 84

Why do populations grow more slowly as they approach their carrying capacity?

Answer 84

Density-dependent factors lead to fewer births and increased mortality.

Question 85

Which of the following life history traits can potentially influence effective population size (Ne)?

a) maturation age
b) gene flow between geographically separated populations
c) genetic relatedness among individuals in a population
d) family and population size
e) All of the options are correct.

Answer 85

e) all of the options are correct

Question 86

Which of the following conditions is the most likely indicator of a population in an extinction vortex?

a) The population is no longer connected by corridors.
b) The species in question is found only in small pockets of its former range.
c) The effective population size of the species falls below 500.
d) The population is geographically divided into smaller populations.
e) Genetic measurements indicate a loss of genetic variation over time.

Answer 86

e) genetic measurements indicated a loss of genetic variation over time

Question 87

You are trying to determine if a particular species will become invasive in your province. You know there are common attributes of invasive species; which attribute would be least applicable to invasive species?

a) high reproductive output
b) known to be invasive in many countries
c) well-developed dispersal mechanisms
d) fast maturation
e) low ecological tolerance

Answer 87

e) low ecological tolerance

Question 88

Although extinction is a natural process, current extinctions are of concern to environmentalists because

a) more animals than ever before are going extinct.
b) the rate of extinction is unusually high.
c) current extinction is primarily affecting plant diversity.
d) most current extinctions are caused by introduced species.
e) None of the options are correct.

Answer 88

b) the rate of extinction is unusually high

Question 89

Which of the following terms includes all of the others?

a) species diversity
b) species richness
c) ecosystem diversity
d) biodiversity
e) genetic diversity

Answer 89

d) biodiversity

Question 90

In a typical grassland community, which of the following is the primary consumer?

a) snake
b) grasshopper
c) hawk
d) grass
e) shrew

Answer 90

b) grasshopper

Question 91

Which trophic level is most vulnerable to extinction?

a) producer level
b) tertiary consumer level
c) primary consumer level
d) secondary consumer level
e) decomposer level

Answer 91

b) tertiary consumer level

Question 92

Which of the following statements best describes the effect of climate on biome distribution?

a) Correlation of climate with biome distribution is sufficient to determine the cause of biome patterns.
b) Not only is the average climate important in determining biome distribution, but so is the pattern of climatic variation.
c) Average annual temperature and precipitation are sufficient to predict which biome will be found in an area.
d) Seasonal fluctuation of temperature is not a limiting factor in biome distribution if areas have the same annual temperature and precipitation means.
e) Temperate forests and grasslands are different biomes because they receive a different quality and quantity of sunlight, even though they have essentially the same annual temperature and precipitation.

Answer 92

b) Not only is the average climate important in determining biome distribution, but so is the pattern of climatic variation

Question 93

In which of the following terrestrial biome pairs are both parts dependent upon periodic burning?

a) desert and savanna
b) tropical forest and temperate broadleaf forest
c) tundra and coniferous forest
d) grassland and tundra
e) chaparral and savanna

Answer 93

e) chaparral and savanna

Question 94

Which pattern of reproduction is correctly paired with a species?

a) semelparity—rabbit
b) iteroparity—elephant
c) semelparity—oak tree
d) iteroparity—Pacific salmon
e) semelparity—polar bear

Answer 94

b) iteroparity - Elephant

Question 95

Which of the following is primarily responsible for limiting the number of trophic levels in most ecosystems?

Answer 95

Energy transfer between tropic levels is in almost all cases less than 20% efficient

Question 96

A population of white-footed mice becomes severely overpopulated in a habitat that has been disturbed by human activity. Sometimes intrinsic factors cause the population to increase in mortality and lower reproduction rates to occur in reaction to the stress of overpopulation. Which of the following is an example of intrinsic population control?

Answer 96

Females undergo hormonal changes that delay sexual maturation and many individuals suffer depressed immune systems and die due to the stress of overpopulation

Question 97

Overexploitation encourages extinction and is most likely to affect

Answer 97

large animals with low intrinsic reproductive rates

Question 98

In the development of terrestrial biomes, which factor is most dependent on all the others?

Answer 98

the species of colonizing animals

Question 99

Natural selection involves energetic trade-offs between

Answer 99

high survival rates of offspring and the cost of parental care

Question 100

Which of the following scenarios would provide the most legitimate data on population density?

Answer 100

Count the number of pine trees in several randomly selected 10 m x 10 m plots and extrapolate this number to the fraction of the study area these plots represent.

Question 101

Which of the following statements best describes the effect of climate on biome distribution?

Answer 101

not only is the average climate important in determining bio distribution but so is the pattern of climatic variation

Question 102

Imagine five forest communities, each with 100 individuals distributed among four different tree species (W, X, Y, and Z). Which forest community would be most diverse?

a) 70W, 10X, 10Y, 10Z
b) 40W, 30X, 20Y, 10Z
c) 100W, 0X, 0Y, 0Z
d) 25W, 25X, 25Y, 25Z
e) 50W, 25X, 15Y, 10Z

Answer 102

d) 25W, 25X, 25Y, 25Z

Question 103

Which of the following is an example of a local biogeochemical cycle?

O2 released by oak trees in a forest

excess NO3- converted to N2 by denitrifying soil bacteria

CO2 absorbed by phytoplankton in the open ocean

organic carbon remains of a leaf being converted to CO2 by a fungus

phosphorous being absorbed from the soil by a corn plant

Answer 103

phosphorous being absorbed from the soil by a corn plant

Question 104

Which of the following statements is consistent with the principle of competitive exclusion?

Natural selection tends to increase competition between related species.
Bird species generally do not compete for nesting sites.
Two species with the same fundamental niche will exclude other competing species.
The random distribution of one competing species will have a positive impact on the population growth of the other competing species.
Even a slight reproductive advantage will eventually lead to the elimination of the less well-adapted of two competing species

Answer 104

Even a slight reproductive advantage will eventually lead to the elimination of the less well-adapted of two competing species

Question 105

Deserts typically occur in a band at 20 degrees north and south latitude because

Answer 105

descending air masses tend to be cool and dry

Question 106

In temperate lakes, the surface water is replenished with nutrients during turnovers that occur in the

Answer 106

autumn and spring

Question 107

Which of the following statements does not apply to the logistic growth model?

The model assumes that populations approach K smoothly.

(K-N)/K is the fraction of K that is available for population growth.

The logistic model of population growth produces a sigmoid growth curve.

When N = K, the per capita rate of increase is small.

When the population is large, then (K-N)/K approaches 0.

Answer 107

When N = K, the per capita rate of increase is small.

Question 108

Why is territoriality an adaptive behaviour for songbirds maintaining populations at or near their carrying capacity?

Answer 108

Songbird males defend territories commensurate with the size from which they can derive adequate resources for themselves, their mate, and their chicks.

Question 109

Which of the following are important biotic factors that can affect the structure and organization of biological communities?

temperature, water

light intensity, seasonality

predation, competition

nutrient availability, soil pH

precipitation, wind

Answer 109

predation, competition

Question 110

Turnover of water in temperate lakes during the spring and fall is made possible by which of the following?

a) cold, more dense water layered at the bottom
b) warm, less dense water layered at the top
c) a distinct thermocline between less dense warm water and cold dense water
d) currents generated by nektonic animals
e) the changes in the density of water as seasonal temperatures change

Answer 110

e) the changes in the density of water as seasonal temperatures change

Question 111

Logistic growth of a population is represented by dN/dt =

Answer 111

rN K-N/K