Exam 13: Population Dynamics Over Space and Time

Human activity can affect metapopulations. Under the basic model of metapopulation dynamics, when humans make it easier for individuals to travel between patches, the probability of _____ and the proportion of occupied patches _____.

Which trait(s) is/are likely to cause less-stable population fluctuations over time? I. short generation time II. small body size III. high sensitivity to environmental conditions

Consider four populations of island birds. Each island has a different carrying capacity, and the birds are subject to environmental and demographic stochasticity. Which population is LEAST likely to go extinct?

Which is an example of a metapopulation? I. Insects live in isolated patches of forest surrounded by agriculture. Sometimes the population in a patch goes extinct, but eventually the insects recolonize that patch. II. A species of bird is found in Canada during the summer. In the fall, the species migrates to the Caribbean and spends the winter there. In the spring it returns to Canada. III. A species of fish lives in a fast-flowing cold river. A dam is constructed on the river, causing the fish to go extinct because of warmer water.

In population dynamics following the logistic model, an overshoot occurs when

Which correctly describes metapopulations? I. They can arise from habitat fragmentation. II. The frequency of occupied habitats is due to the balance of extinction and colonization. III. The basic metapopulation model assumes that all patches are equal in quality.

When comparing larger animals to smaller animals we tend to see more stable population sizes in larger animals. What might be a reason this is the case?

Which panel is most likely to indicate a population with a constant environment and no time delays in density dependence?

Grasslands used to be spread across large portions of North America. However, human land use has separated formerly large, continuous grassland into many smaller isolated patches. This is an example of

The females of a certain species of fish produce on average 1,000 eggs each year. By chance some females produce a few more eggs than average, and others produce slightly fewer eggs than average. This is an example of

A population die-off occurs when I. a species' resources are depleted. II. an overshoot occurs. III. carrying capacity is exceeded.

The observation that three species of grouse in Finland all experience natural population cycles every 6-7 years in synchrony is evidence that

That a predator finds itself in an environment with increased prey, yet does not immediately convert the prey consumed in such a resource-rich environment into offspring is the foundation for the idea of

In the logistic growth model with time delays, the product of r indicates the

Consider a logistic model that includes a time delay in density dependence and exhibits damped oscillations. If the intrinsic rate of increase is reduced but all other parameters remain the same, which of the following outcomes is most likely?

Which type of model always includes random variation?

Consider a population with the following numbers of individuals over time. year 1: 10 Year 2: 25 Year 3: 30 If the population size in year 4 is determined by a logistic model with delayed density dependence from a 1-year time lag and K = 50 individuals, what value of r would lead the population size to exceed carrying capacity in year 4?

Which panel illustrates a stable limit cycle?

When immigrants supplement a declining subpopulation, they prevent the subpopulation from going extinct. This phenomenon is known as

Two species of mice are similar in many characteristics. However, species A has large fat reserves that increase survival over periods when environmental resources are depleted, while species B has no fat reserves. Which species is more likely to exhibit oscillating population dynamics? Explain your answer.