Exam 12: Population Growth and Regulation

The following table shows the survival and fecundity of a flowering plant. Use it to answer questions 47 to 49. -What is the generation time (T) of this species?

The Allee effect describes

Which describes the figure of logistic population growth shown in the graph?

In the logistic growth model, in which of the following conditions is the overall rate of increase the highest?

Which form of population growth results in an S-shaped curve?

Which illustrates a negative relationship between population density and the average size of individuals over time?

The intrinsic growth rate, r, is

Consider a perennial plant with four life stages: seed, seedling, small adult, and large adult. Seeds survive to seedlings with a probability of 50 percent; seedlings survive to be small adults with a probability of 20 percent; small adults survive to be large adults with a probability of 20 percent. Both small adults and large adults produce an average 10 seeds. Use this information to fill in the life table that follows; then calculate the R₀ and explain whether the population is increasing, stable, or decreasing. R₀: _____________________

Alpine ibex are a type of wild goat that lives high in the mountains. During winters with heavy snow, Alpine ibex have high mortality rates, but when winters have little snow, Alpine ibex have low mortality rates. This is an example of

Which is likely to follow an exponential increase in population size? I. a population of mice that has consumed most of the food in its habitat II. a small population of rats recently introduced to an island with many resources III. bacteria recently placed on a new Petri dish with suitable growth medium

In what way is the geometric growth model different from the exponential growth model?

The logistic growth model describes a maximum population size that is

If a population has relatively few individuals in the young classes but many in the medium-aged and old classes, what can we conclude about population growth?

The following table for a species of plant that has four life stages was constructed from research done in the 1960s. Forty years later, biologists went back to the same site and determined the life table for the population, shown in the following table. On account of changing climatic conditions, seed survival decreased from 30 percent to 10 percent. However, these changing climactic conditions also cause large adults to produce four times as many seeds, so that they now produce 200 seeds. All other variables stay the same. Explain whether the change in climate is beneficial or harmful to this plant population based on these tables. Be sure to reference any relevant calculations you should make and explain the relative importance of the decreased seed survival and increased seed production.

The graph shows one possible answer; students will have their own values. The figure should show log-transformed mass on the y axis and log-transformed survival on the x axis. The points they plot should form a negative slope. -(Alternative version with different figures.)A biologist studies a population of birds for 25 years. Each year the biologist records the amount of rainfall and the density of birds (number of birds per 100 square metres). Additionally, the biologist determines the survival rate for eggs laid that year. The biologist then plots egg survival rate against both rainfall (graph a) and density (graph b). In each plot the individual points represent the data for one year of the study. Based on these data, does this population of birds appear to be subject to positive density-dependent population regulation, negative density-dependent population regulation, or density-independent population regulation? As part of your answer, list the prediction for each type of population regulation and explain whether the data meet that prediction.

Use the following information and life tables to answer questions 44 to 46. Recently, it has been hypothesized that coyotes living in urban environments can control the populations of geese living in public parks. To test this hypothesis, a biologist compares two populations of geese. Coyotes are removed from one park but allowed to remain in another park. Both populations contain 1000 geese when the experiment begins. -Which is correct about the geese in these populations? I. When coyotes are removed, goose R₀ > 1. II. When coyotes are removed, goose R₀ < 1. III. When coyotes are present, goose R₀ > 1. IV. When coyotes are present, goose R₀ < 1.

Which is the most accurate statement about the conservation biology of species with positive density-dependent population regulation?

Which describes this population? I. The population has a stable age distribution. II. The population's growth is consistent with a geometric model. III. The population's growth is consistent with a logistic model in which K = 1900.

Describe how the geometric growth model is different from the exponential growth model. For each growth model, give an example of an organism that fits the growth pattern it describes. Explain why the organism fits the model.

In a population growing according to the exponential growth model, population size is