Exercise 10 Flashcards
What are the four main patterns of population growth observed in nature?
A. Linear, exponential, logistic, and fluctuating
B. Linear, logistic, fluctuating, and cycling
C. Exponential, logistic, quadratic, and cycling
D. Exponential, logistic, fluctuating, and cycling
D. Exponential, logistic, fluctuating, and cycling
How is exponential growth related to logistic growth?
A. Both exponential growth and logistic growth show a rapid increase in the number of individuals in the population at first, but then logistic growth slows down and stabilizes at the minimum population size.
B. Both exponential growth and logistic growth show a rapid increase in the number of individuals in the population at first, but then logistic growth slows down and stabilizes at the maximum population size.
C. Both exponential growth and logistic growth show a slow increase in the number of individuals in the population at first, but then exponential growth speeds up until resources are exhausted.
D. Both exponential growth and logistic growth show a rapid increase in the number of individuals in the population at first, but then logistic growth speeds up until resources are exhausted.
B. Both exponential growth and logistic growth show a rapid increase in the number of individuals in the population at first, but then logistic growth slows down and stabilizes at the maximum population size.
Which of the following is true about population size fluctuations seen in nature?
A. Fluctuations occur in all populations.
B. Fluctuations eventually become a regular cycle with constant, or nearly constant, time intervals.
C. The rise and fall of population sizes should be analyzed using a mean value.
D. None of the above incorrect
A. Fluctuations occur in all populations.
Why is there often a time lag in a population’s response to changes in its population size?
A. Because of limits on the carrying capacity
B. Because of limits on exponential growth
C. Because of delayed growth, reproduction, and/or survival
D. Because of immediate growth, reproduction, and/or survival
C. Because of delayed growth, reproduction, and/or survival
What mechanism(s) explain the population cycles seen in some predator-prey interactions?
A. Delayed predator population growth to prey population growth
B. Matching predator and prey population growth
C. Random fluctuations in predator population growth
D. All of the above
A. Delayed predator population growth to prey population growth
How could you cause a population to cycle?
Provide unlimited food for both adults and juveniles in the population
Provide limited food for both adults and juveniles in the population
Provide unlimited food for the adults but limit the food for juveniles in the population
Provide unlimited food for the adults but no food for juveniles in the population
Provide unlimited food for the adults but limit the food for juveniles in the population
Which of the following best describes why fluctuations in population growth rate can increase a population’s risk of extinction?
Compared to populations that do not fluctuate, populations that fluctuate in size show no change in growth rates, resulting in the same population sizes with the same risk of extinction.
Compared to populations that do not fluctuate, populations that fluctuate in size show faster growth rates, resulting in larger population sizes with lower risk of extinction.
Compared to populations that do not fluctuate, populations that fluctuate in size show slower growth rates, resulting in smaller population sizes with less risk of extinction.
Compared to populations that do not fluctuate, populations that fluctuate in size show slower growth rates, resulting in smaller population sizes with greater risk of extinction.
Compared to populations that do not fluctuate, populations that fluctuate in size show slower growth rates, resulting in smaller population sizes with greater risk of extinction.
Why do small populations that experience genetic drift and inbreeding have an increased chance of extinction?
Genetic drift and inbreeding increase genetic variation, limiting the ability of populations to respond to environmental change and harmful alleles.
Genetic drift and inbreeding reduce genetic variation, limiting the ability of small populations to respond to environmental change and harmful alleles.
Genetic drift and inbreeding reduce genetic variation, increasing the ability of small populations to respond to environmental change and harmful alleles.
Genetic drift and inbreeding reduce genetic variation, increasing the ability of small populations to respond to environmental change and helpful alleles.
Genetic drift and inbreeding reduce genetic variation, limiting the ability of small populations to respond to environmental change and harmful alleles.
A small population of nesting birds experiences an unusual snowstorm, causing some mortality in the population. A survey reveals that 90% of the juvenile birds and 5% of the adult birds die as a result of the storm. What factor best describes this chance event?
Genetic drift
Demographic stochasticity
Environmental stochasticity
Demographic and environmental stochasticity
Demographic and environmental stochasticity
During a hurricane, a large segment of an insect population is carried to a distant island where there are abundant resources and minimal predators. What type of growth would you likely expect in the time immediately following this colonization event?
Logistic
Linear
Declining
Exponential
Exponential
Consider a population of birds that land on an island. Their numbers rise exponentially until they reach a population of 1,000 birds, after which they crash to 700 due to resource limitations. Over time, the population rises and falls until it stabilizes around a population of 850. What does this population size of 850 likely represent in terms of population growth?
Maximum population size
Minimum population size
Carrying capacity
effective population size
Carrying capacity
A population of wolves predates a population of moose on Isle Royale, Michigan, where there are fewer wolves than moose to start. The wolves prey on the moose and eat well, allowing them to have abundant offspring. However, as the wolf population rises, the moose population drops, and over time, the wolf population begins to drop also because of the reduced availability of resources. As the wolf population drops, moose are able to better survive and reproduce, causing the moose population to rise. With this abundance of moose, the wolf population is able to rebound until their population exceeds the moose population’s ability to support the number of wolves. Which population dynamic does this series of oscillations represent?
Delayed density dependence
Delayed density independence
Extinction vortex
Carrying capacity
Delayed density dependence
Assuming that their average population growth rates and all other factors are equal, which population would most likely be at risk for extinction?
A large population with low variation in its growth rate
A large population with high variation in its growth rate
A small population with high variation in its growth rate
A small population with low variation in its growth rate
A small population with high variation in its growth rate
A small population of 100 organisms is only able to contribute 25 offspring to the next generation, but during that time, 30 individuals in the population die. In the next iteration, the remaining 95 individuals generate only 20 offspring, but during that time, 30 individuals of the population die. The remaining 85 individuals generate only 15 offspring, but during that time, 30 individuals of the population die. Which of the following terms best describes what this population is experiencing?
Logistic growth
Exponential growth
Carrying capacity
Extinction vortex
Extinction vortex
Although there are approximately 10,000 cheetahs left in the wild, biologists think that their numbers were much lower at some time in the past because cheetah populations have very little genetic variation. What is the most likely reason for the lack of genetic variability in cheetahs?
Environmental stochasticity
Demographic stochasticity
Genetic stochasticity
Genetic drift
Genetic drift
