EXAM 2
A population of biennial plants (composed of seeds, one-year-old plants, and two-year-old plants) is affected by a fungal disease that causes mortality of some one-year-old plants. If the demographic matrix for this population is school(36).jpg , what value would you change to assess how much conservation benefit could be gained by applying a fungicide to the plants? CHAP 9
0.6 This is the probability that a one-year-old plant survives to become a two-year-old plant. And since the fungal disease causes mortality of one-year-old plants, this is the value you would want to change to assess the potential conservation benefits of spraying a fungicide to control the pathogen.
A population of biennial plants (composed of seeds, one-year-old plants, and two-year-old plants) is affected by deer that graze off some of the flowering stems and thereby reduce the average number of seeds produced per plant. If the demographic matrix for this population is school(37).jpg, what value would you change to assess how much conservation benefit could be gained by fencing out the deer CHAP 9
10 is the average number of seeds produced per two-year-old plant, and this is the value that you would change to assess the potential conservation benefits of fencing out deer.
A population of biennial plants (plants that reproduce only in their second year of life and then die) consists of 150 seeds, 25 one-year-old (vegetative) plants, and 10 two-year-old (flowering) plants. If the demographic matrix for the population is school(34).jpg , then in the next year the population will consist of CHAP 8
205 seeds, 30 one-year-old plants, and 15 two-year-old plants.
Which of the following is a key lesson learned from metapopulation models?
A key lesson learned from metapopulation models is that a reduction in dispersal success can cause the metapopulation to become extinct. This means, among other things, that the land between habitat patches must be sufficiently hospitable to dispersing individuals. Also, the arrangement and connectivity of patches can be just as important as the absolute amount of habitat. Reduced dispersal success can cause a metapopulation to become extinct.
Which of these statements about population bottlenecks is NOT true?
A population will generally have lower genetic diversity after rather than before a population bottleneck. A population bottleneck is a pronounced drop in population size followed by a population recovery. A population bottleneck will lower the effective population size. NONE OF ABOVE--
Active intervention is likely needed to restore areas of high productivity and low stress because
Active removal of invasive species may be needed in areas of high productivity and rapid growth. such conditions could favor the rapid growth of invasive species.
Which of the following risks might be the result of a disruption to group behaviors such as hunting or communal rearing of young?
Allee effect is a positive relationship between individual fitness and population size. It is a risk to population persistence because low population size causes rates of survival and birth to fall even lower, potentially due to the disruption of group behaviors.
Using a species' current level of genetic diversity to estimate its historic population size requires data, or at least a range of assumptions, about all of the following, except
Approaches that try to use information about modern genetic diversity to estimate historic population size focus exclusively on selectively neutral loci (stretches of DNA that do not code proteins or RNAs). Therefore, the strength of natural selection would not be a necessary piece of data for this calculation. the strength of natural selection.
According to the figure below, restoration is most likely to occur spontaneously and without extensive human intervention in areas with CHAP 11
Areas of moderate productivity and stress are most likely to experience spontaneous succession. moderate productivity and moderate stress.
Why is an individual whose parents are closely related likely to suffer reduced fitness?
Because inbreeding increases homozygosity, and homozygous individuals can sometimes produce only one version of a protein, the offspring of closely related parents can be at a disadvantage relative to heterozygotes. Because inbreeding increases the chance that an individual will carry two copies of a rare harmful recessive allele. Inbreeding can reduce individual fitness both by disrupting the advantage that heterozygotes sometimes enjoy and by bringing together two copies of rare and harmful recessive alleles.
Why does allelic diversity (the number of different forms of genes) tend to decline in small, isolated populations?
Because the loss of alleles due to genetic drift will likely outpace the rate of mutation. Because there are few individuals, possibly carrying new alleles, moving into an isolated population. Allelic diversity tends to decline in a small, isolated population due to the combination of strong genetic drift and limited gene flow into the population.
Keeping in mind that the Middle Columbia River is the control site and the Snake and Upper Columbia Rivers are the impact sites, which of these statements is NOT consistent with the patterns shown in the figure below? CHAP 9
Before dam construction, the Middle Columbia River had more spawners than the Snake River. This statement is NOT consistent with the bar at left in graph B, which shows that before dam construction, the Snake River had more spawners than the Middle Columbia River.
Some conservationists have questioned the value of identifying biodiversity hotspots because
Biodiversity hotspots have been criticized for being overly sensitive to the particular metrics of biological value, not factoring in feasibility, and failing to consider ecosystem services.
According to the figure below, CHAP 10
Bryce Canyon is smaller than Olympic National Park and has lost a greater number of mammal species than Olympic. . The figure shows that Bryce Canyon has lost four mammal species and is smaller than Olympic National Park, where no mammals have become extinct.
Which of these factors will make a population LESS prone to lose genetic diversity due to genetic drift?
Compared to a fluctuating population, a stable population is less prone to lose genetic diversity due to drift. Stable population size
Which of these statements about marine conservation planning is NOT accurate?
Conservation planning was initially focused on marine environments and only recently shifted to pay attention to terrestrial environments. In fact, conservation planning for marine habitats has lagged far behind terrestrial efforts.
If the demographic matrix for a population of biennial plants (composed of seeds, 1-year-old plants, and 2-year-old plants) is school(36).jpg , what percentage of seeds dies each year? CHAP 8
Correct. 70% of seeds remain as viable ungerminated seeds and 20% germinate and grow into 1-year-old plants. The remaining 10% perish. 10%
Which of the following risks is the result of random variation in the survival and production of offspring and is especially of concern for a small population?
Demographic stochasticity is random variation among individuals in birth rate, death rate, and sex of offspring. The importance of demographic stochasticity as a potential cause of extinction declines quickly with population size. demographic stochasticity
Habitat fragmentation can lead directly to all of the following except
Environmental stochasticity is a phenomenon that occurs regardless of habitat fragmentation.
Which of the following risks is due to random variation in the survival and production of offspring due to fluctuating weather conditions or species interactions?
Environmental stochasticity is variation in the expected rates of survival and birth due to changing environmental conditions.
Which of the following is an assumption of an ideal population?
Equal numbers of breeding males and females An ideal population assumes an even sex ratio among breeding individuals.
Imagine two populations have allele frequencies p1 = 0.3, q1 = 0.7, and p2 = 0.8, q2 = 0.2. What is the value of FST for this scenario?
FST = (0.495 - 0.370)/0.495 = 0.253. 0.253
Which of these statements is consistent with the patterns shown in the figure below? CHAPTER 7
Heterozygosity is lost more quickly in populations with relatively smaller effective population size. The more generations that a population remains at a small effective population size, the more genetic diversity it will lose.
If you used a Lincoln Petersen mark-recapture approach to estimate the size of an animal population, but the tags were defective and fell off some percentage of the originally sampled individuals, the method would tend to
If some marked individuals lose their tags, you could underestimate the number of recaptured individuals, r, because some animals might be recaptured but you won't know this due to the lack of a tag. The effect of this error is to inflate N, the estimated number of individuals in the population. overestimate the true population size
If you used a Lincoln Petersen mark-recapture approach to estimate the size of an animal population, but the tags were attractive to predators, the method would tend to
If tagged individuals are disproportionately lost from the population, the proportion of individuals recaptured (r/s) will be reduced, which will cause you to overestimate the true population size. overestimate the true population size.
The answer to the single large or several small (SLOSS) debate concerning optimal reserve design is
If there is a high degree of species nestedness, a greater number of species could be protected with a single large reserve. However, if there is a low degree of species nestedness, a greater number of species could be protected in a collection of several small reserves. either a single large or several small reserves could harbor a greater number of species, depending on the degree of species nestedness across areas of different sizes.
Which of the following would be not be expected near the edge of a forest patch compared to the patch interior?
In fact, a greater abundance and diversity of nonnative species is expected near the forest edge. Lower abundance and diversity of nonnative species
All of the following statements are consistent with the simple metapopulation model shown in the figure below, except the rate of
In the figure, the rate of colonization is lower than the rate of extinction when the fraction of patches occupied is above f*. colonization is greater than the rate of extinction when the fraction of patches occupied is above f*.
You suspect that mortality of the little brown bat (Myotis lucifugus) is related to the presence of a fungal pathogen that causes a disease known as white nose syndrome. Based on a single year of fieldwork, you have estimates of mortality rate for six populations where the fungal pathogen is present and five populations where it is absent. Which kind of observational study would probably be best suited to this scenario?
In this case the predictor variable (presence or absence of the fungal pathogen) is a categorical variable, which rules out a regression approach. Also, you have data from only one year, so a BACI is not possible. Control-impact study
Which of the following risks is due to the reduction in survival and birth rates that sometimes results when an individual s mother and father are closely related?
Inbreeding depression is the reduction of individual fitness due to mating among more closely related individuals.
If a species is very rare, a manipulative experiment may not be feasible because
Legal, logistical, and ethical issues may preclude the implementation of manipulative experiments involving very rare species. the manipulation may be illegal if it could jeopardize the future of the species. there may be so few individuals or populations remaining that it isn t possible to achieve a sufficient level of replication. the experiment might require ethically questionable manipulations, such as intentionally introducing a nonnative species to see what impact it has on the rare species.
Which of these statements would not provide evidence of the shifting baselines phenomenon?
Molecular studies revealed that a high amount of genetic diversity persists among the few remaining Toromiro trees. This result does not provide evidence of the shifting baseline phenomenon. The shifting baseline phenomenon describes how human perceptions of "normal" conditions shift across generations.
You suspect that mortality of the little brown bat (Myotis lucifugus) is related to the mean daytime temperature in February. Based on your fieldwork, you have estimates of the mortality rate for little brown bats in 15 locations widely dispersed across North America. Which kind of observational study would probably be best suited to this scenario?
Regression study In this case, the predictor variable (mean daytime temperature in February) will likely vary across a continuous numerical range, and you could use a regression approach to see if there is a relationship between bat mortality and temperature across the 15 locations
Capturing sick or injured individuals from the wild, treating them, and releasing them back into the wild is called
Rehabilitation involves treating sick or injured individuals and then releasing those same individuals back into the wild.
If you used a Lincoln Petersen mark-recapture approach to estimate the size of an animal population, but tagging individuals affected their probability of recapture, the method would tend to
The answer is that it depends. If tagging increases the probability of recapture, then the method will tend to underestimate the true population size. However, if tagging reduces the probability of recapture, then the method will tend to overestimate the true population size. either underestimate or overestimate the true population size, depending on whether tagging increases or decreases the probability of recapture.
Efforts to breed and reintroduce the California condor have cost tens of millions of taxpayer dollars. Why might these efforts end up being unsuccessful?
The continued use of lead ammunition, only recently banned, has caused lead poisoning of many condors. Lead ammunition is strongly implicated as a major cause of mortality and illness among today's non-captive California condor populations.
The figure below shows the relationship between the effective population size and the variance in offspring production for a population consisting of N = 100 individuals. Which of these statements is consistent with the patterns shown in this graph? CHAPTER 7
The effective population size (Ne) can equal the raw count of individuals (N). Specifically, Ne = N when the variance in the number of offspring per individual equals 2. Effective population size can equal the raw count of individuals (N).
If population growth rates over three periods are λ = 0.9, 1.2, and 0.8, the realized rate of change would be
The geometric mean accurately describes the realized rate of change over multiple time periods. 0.952
Which of these statements regarding the survival of Snake River spring/summer Chinook salmon from their spawning grounds to the Lower Granite Dam is supported by the data shown in the figure below? CHAP 9
The presence of brook trout reduces salmon survival, but this effect is evident only in high-quality habitat. In low-quality habitat, salmon survival is low regardless of whether brook trout are present. The negative effects of brook trout on salmon survival are apparent only in high-quality habitat.
According to the figure below, the rate of colonization increases as CHAP 10
The rate of colonization is higher on islands that are nearer to the mainland. You can see this by comparing the colonization curves for the near and far islands DISTANCE FROM THE MAINLAND DECRASES
According to the figure below, the rate of extinction increases as CHAP 10
The rate of extinction is greater when there are more species present on an island. You can see this by noting that the steepness of the extinction curve increases as the number of species increases. the number of species present on the island grows
Imagine you want to build a demographic matrix model for a population of a long-lived shrub species that flowers year after year. You would likely want to use a model that is
The shrub's size is probably a good indicator of its probability of survival and fecundity, and because shrubs can become smaller (due to herbivory, disease, or broken branches), size is probably a better indicator of survival and fecundity than age. size-based.
Conservation plans that prioritize the continued delivery of ecosystem services to people
There is no evidence of any correlation between biodiversity and the provision of ecosystem services. However, it is possible to prioritize protection of sites that happen to have high biodiversity and provide highly valuable ecosystem services. may or may not protect large amounts of biodiversity, but opportunities for win-win outcomes exist.
According to the figure below, restored sites CHAP 11
This figure shows that levels of biodiversity, ecosystem function, and regulating ecosystem services are higher in restored sites than in degraded sites but lower in restored sites than in reference sites. provide greater levels of regulating ecosystem services than degraded sites but lower levels than reference sites.
To perform even the most basic population viability analysis requires all of the following, except an estimate of the
This information could be useful in a more sophisticated PVA, but it is not essential for the most basic version. rate of movement among subpopulations.
This simple model of exponential population change, Nt + 1 = λNt, assumes all of the following, except
This model makes no assumption about random or nonrandom mating. completely random mating.
A large value of FST (the inbreeding coefficient) relative to FST values calculated for similar types of species indicates that
a dispersal corridor may be a good investment because migration between subpopulations is currently limited. A relatively large value of FST indicates there is relatively little migration connecting the focal populations, so a dispersal corridor could potentially be beneficial.
A well-designed manipulative experiment has all of the following features, except
background variability that masks any clear signal that might be attributed to the experimental conditions. Background variability unrelated to the experimental treatments is a problem for any study, but a well-designed manipulative experiment tries to overcome this problem via replication, randomization, and efforts to control, or hold constant, potentially confounding variables.
The figure below shows a positive relationship between the amount of parrotfish grazing and the recruitment of young corals. The explanation for this relationship is that parrotfish CHAP 9
eat algae off the surface of the corals that might otherwise interfere with coral growth. Parrotfish graze the algae that might otherwise overgrow and kill the corals.
Zoos have become important players in conservation by
educating the urban public and eliciting broad support for conservation. providing a last-ditch opportunity for captive breeding and possible reintroduction of highly threatened species. paying detailed attention to the pedigree of individuals and managing worldwide collections as single populations for breeding purposes. Zoos play an important role in public education and serve as the repositories of most, if not all, of the extant individuals of many extremely threatened species.
Conservation planners typically use computer algorithms to select a suite of priority sites for protection. These algorithms tend to select sites on the basis of
efficiency or, in other words, coming as close as possible to the stated conservation goals within a fixed budget of land area or money. The computer algorithms seek the set of sites that maximize the conservation goals while remaining within a fixed budget of land area or money.
Conservation planners can incorporate the anticipated effects of climate change by identifying areas that
encompass both the current and the projected future distribution of conservation targets. capture the entire spectrum of soil types, topographic features, and climatic conditions. provide for the continuation of key ecosystem processes such as sediment retention along a river.
Conservation International (CI) identified 25 biodiversity hotspots as areas harboring especially large numbers of
endemic plant species combined with high rates of habitat conversion. CI's hotspots harbor at least 2,500 endemic plant species and have lost at least 70% of their original vegetation due to land conversion.
Dispersal corridors can benefit a species by
facilitating recolonization of an area following local extirpation. facilitating gene flow that can alleviate inbreeding depression. Dispersal corridors can benefit a species by facilitating recolonization following local extirpation and by facilitating gene flow that can alleviate inbreeding depression.
Critics of dispersal corridors worry that corridors may
function as an ecological trap. cause outbreeding depression or disrupt the evolutionary divergence of isolated populations. facilitate the movement of nonnative organisms among habitat patches. Critics of dispersal corridors are concerned about all of the above potential negative consequences
According to the figure below, the island Isabela CHAP 10
harbors fewer native land-bird species than all the other Galápagos Islands combined, despite the fact that Isabela is larger than the cumulative area of the other islands. The other islands of the Galápagos combined offer breeding sites for all 26 native land-bird species in nearly half the total area of Isabela.
Hatcheries can be harmful to wild populations for all of the following reasons, except
hatcheries can quickly generate large numbers of individuals. The rationale for hatcheries is that they have the potential for quickly producing many individuals to reduce the probability of extinction in the near term. NOT ANSWERS hatchery-raised individuals may be larger than wild individuals at the time of release. hatcheries select for traits well suited to domestication. hatcheries can reduce the genetic diversity of a population.
The 30-year-long effort in India to census the nation s tiger population could have been improved by any of the following, EXCEPT
hiring more people to conduct a more thorough search for pugmarks. Hiring yet more people to conduct searches in the same way would not have improved the effort.
An ecoregion is a large area of land or water that
is characterized by a relatively distinct set of environmental conditions and species. An ecoregion does not necessarily follow geopolitical boundaries and is instead defined by the relatively unique environmental conditions and species found within the region.
The figure below shows that red hot poker plants planted in small groups (with few other red hot poker individuals) did not produce as many seeds per plant compared to individuals planted in large patches. This happened CHAPTER 7
only when birds were able to access the plants. The fitness of individual plants was positively related to patch size, but only when birds were able to access the plants. This evidence of the Allee effect occurs because birds are less likely to visit and pollinate flowers that exist in small patches.
The main goal of gap analysis is to identify
priority areas for protection that harbor large concentrations of relatively unprotected conservation targets.
A restoration project may seek to
recreate historical conditions. create habitat for particular species of conservation concern. promote particular ecosystem functions.
The active removal of pollutants from the environment is called
remediation Remediation is the active removal of pollutants from soil or water.
Conservation planners commonly assume that efforts focused on a subset of well-chosen conservation targets will protect all, or least most, of the biodiversity in the ecoregion. Studies assessing the effectiveness of targeting a small number of species in a conservation plan have shown that
targeting specific kinds of species is generally no better than targeting a random selection of species. Plans built around particular kinds of species thought to be good indicators of overall biodiversity performed no better than plans built around species selected at random
Population viability analysis (PVA) can be used to estimate
the probability of extinction within some specified time period. the expected (average) population size at some specified future time. the range of population sizes that is likely (say with 95% confidence) at some specified future time.
