Chapter 3

Which water depth had the biggest difference in survival rates for embryos with UV-B protection versus embryos without UV-B protection?

10 cm

Which of the following statements best describes the relationship between UV-B transmission and embryo survival rates shown on the graph?

At shallow depths UV-B transmission is high and unprotected embryo survival rates are low.

Consider the effects of several drier-than-average years on the western toad population. If the average depth of pools available for toad spawning declines, what other effects might be associated with the drier climate?

Lower than average embryo survival rates.

Can you identify the process by which camouflage causes a beetle population to undergo natural selection? To review the process of natural selection, watch this BioFlix animation: Mechanisms of Evolution: Natural Selection. Part A - Natural selection: CamouflagePart complete Drag the labels onto the flowchart to indicate the correct sequence.

View phone

Members of two separate species cannot __________.

interbreed

The appearance of an evolutionary novelty often promotes _____.

adaptive radiation

According to the figure, which of the following birds is most closely related to the Palila?

Laysan Finch

Activity: Causes of Evolutionary Change Part B Click on the diagram to start the animation. What process is illustrated by this animation?

NOT mutation HINT This is natural selection, since environmental conditions dictate that green individuals are more likely to reproduce than are red individuals.

As a population approaches carrying capacity, environmental resistance __________.

NOT remains constant

A community ecologist would study which of the following?

patterns of interactions between wolves and coyotes in Yellowstone National Park

Extinction is ________.

the disappearance of a species from Earth

__________ is the visitation of natural areas for enjoyment, often in areas near less-affluent communities that economically benefit from conserving the natural area.

Ecotourism

Which of the following is accurate?

Ecotourism combines wildlife conservation with economic benefits.

Mass extinctions create conditions that promote _____.

adaptive radiation

For two organisms to belong to the same species, individuals of their species must __________.

be able to reproduce and have fertile offspring

According to the figure, crocodiles are most closely related to ________.

birds

Which of these organisms has a survivorship curve similar to that of oysters?

grasses

Density dependent factors

have a greater impact at higher population densities

Density-dependent factors ________.

include the effects of disease, predators, and food on a single species within a community

Which of the following factors does not contribute to environmental resistance?

birth rate

Which of the following is the broadest (most all-encompassing) level of ecological organization?

the biosphere

When the organisms of a particular population seek habitats or resources that are unevenly spaced, the distribution of the individuals in the population tends to be ________.

NOT random

Which of the following statements are true of logistic growth? Select all that apply.

-When the population reaches carrying capacity, it stops growing. -As the population approaches carrying capacity, it grows more slowly.

Scientists grew a population of yeast cells in a flask to which they provided a constant supply of nutrients. As the population of yeast cells increased, competition for the nutrients also increased. This caused the population to grow more slowly, until the rate at which the yeast cells used the nutrients was equal to rate at which the nutrients were supplied to the flask. Which of the three graphs shown in Part G best represents the growth of these yeast population?

Graph A

The key to the success of this product lies in which of the following?

NOT Bedbugs must touch the chemical secreted by the fungus.

Entomopathogenic fungi would likely be most successful in helping with which of the following outbreaks?

NOT Influenza B, spread without a vector.

Your home is infested with bedbugs. You search for a chemical-free alternative. Which of the following would be your best option?

The use of high temperatures.

A coyote, which can alter its food intake to match seasonal abundance of plants, fruits, or small animals, is considered to be ________.

a generalist

Which of these organisms has a survivorship curve similar to that of humans?

elephants

A single, small population that exists only in one place on the planet is considered __________ to that area.

endemic

Populations lacking any environmental resistance tend to increase by ________.

exponential growth

Which of these species typically has a mortality rate that remains fairly constant over an individual's life span?

robins

BioFlix Activity: Population Ecology -- Types of Population Growth Can you identify the different ways in which populations grow? To review types of population growth, watch this BioFlix animation: Population Ecology. Part A - Types of population growth Drag the correct label under each graph to identify the type of population growth shown.

see phone

Graphs A, B, and C represent three different patterns of population growth. Refer to these graphs as you read about the populations in the following questions. A female darkling beetle laid her eggs in a sack of corn meal. The corn meal was an excellent source of food for the beetle larvae (mealworms), and the beetle population quickly increased. After four months, the beetles had eaten all of the corn meal, and the adult beetles flew away to find new food sources. Which graph best represents the growth of the beetle population in the sack of corn meal?

NOT Graph A

According to the figure, which of the following is true?

NOT Reptiles (turtles, snakes, lizards, and crocodiles) are more closely related to each other than they are to any other animals.

Activity: Causes of Evolutionary Change Part C Generation-to-generation change in the allele frequencies in a population is _____.

NOT Natural Selection HINT Generation-to-generation change in the allele frequencies in a population is the definition of microevolution.

Process of Science: What Clues About Evolution Might Road Kill Provide? Part A - Scientific method: Developing hypotheses A group of researchers gathered data on the number of cliff swallow road kills they observed while driving between nest sites in Nebraska. The data cover a period of about 30 years and date back to the time when cliff swallows first started to nest under highway overpasses.As the graph shows, the number of road kills observed declined sharply over time. The data led the researchers to ask themselves this question: What caused this decline? Data from C. R. Brown and M. B. Brown. Where has all the road kill gone? Current Biology 23: R233-R234 (2013). Which of the following are testable hypotheses that could explain the researchers' data? Select all that apply.

-Traits that help individuals avoid being hit by cars have evolved through natural selection in the cliff swallow population. -The population size of cliff swallows living near roads has decreased over time. -Scavenger population sizes have increased, and more road-killed swallows get eaten before they can be found.

Part C - Experimental results: Did the cliff swallows' wings change over time?Part complete The researchers decided to take a closer look at the data they had collected on the shape and length of the cliff swallows' wings.This graph compares the wing length data collected from cliff swallows that were killed on the roads (blue bars) and from cliff swallows in the general population (maroon bars).Analyze the data in the graph and use it to complete the sentences below. Data from C. R. Brown and M. B. Brown. Where has all the road kill gone? Current Biology 23: R233-R234 (2013). Drag the terms on the left to the appropriate blanks on the right to complete the sentences. Not all terms will be used.

1. From 1984 to 2012, the wing length of cliff swallows in the general population generally decreased. 2. During the same time period, the wing length of cliff swallows killed on the roads generally increased. 3. In most years where data was collected, the wings of cliff swallows killed on the roads were longer than the wings of swallows found in the population at large. 4. Shorter wings allow cliff swallows to take off from the ground more vertically, enabling them to better avoid oncoming cars. As a result, cliff swallows in populations near highways with shorter wings have a survival advantage. 5. The data suggest that, over time, natural selection resulted in the evolution of shorter wings in the cliff swallow population. 6. Shorter wings are a(n) adaptation in this population. Alleles for shorter wings were already present in the general population.

Part B - Experimental results: Interpreting the data To test the egg-viability hypothesis, researchers set out to determine whether its predictions were borne out. Predictions of the egg-viability hypothesis include:Prediction #1: The probability of hatching failure will be lower at higher latitudes (because temperatures remain cooler at higher latitudes).Prediction #2:: The probability of hatching failure will be higher later in the season (because temperatures are warmer later in the season).Prediction #3: The probability of hatching failure will be higher in larger clutches (because in a larger clutch, the earlier eggs have to wait longer for incubation to begin).Prediction #4: The probability of hatching failure will be higher for eggs laid earlier within a clutch (because eggs laid earlier in a clutch have to wait longer for incubation to begin).Citizen scientists monitored bluebird nestboxes throughout the breeding season and reported details such as date, location, number of eggs, number of hatchlings, and number of unhatched eggs. The three graphs below show the data they collected.Data from C.B. Cooper et. al. Geographic and seasonal gradients in hatching failure in Eastern Bluebirds Sialia sialis reinforce clutch size trends. Ibis 148: 221-230 (2006).Review the graphs to determine whether the data support the four predictions.Drag the terms to the appropriate blanks to complete the sentences.

1. Graph A shows that the probability of hatching failure increases later in the season. The data support Prediction #2. 2. Graph B shows that the probability of hatching failure decreases at higher latitudes. The data support Prediction #1. 3. Graph C shows that the probability of hatching failure is highest for both the largest and the smallest clutch sizes. The data do not support Prediction #3. 4. Researchers were unable to test Prediction #4. This is because it was too difficult for volunteers to collect data on which eggs were laid earliest.

A pair of coyotes colonized a large island where rodents (their prey) were abundant. At first the number of coyotes increased. But as the coyote population increased, competition for prey also increased and the coyote population grew more slowly. In some years, weather conditions killed many of the rodents, causing some coyotes to starve. In other years, weather conditions were favorable for the rodent poulation, allowing the coyotes to thrive, reproduce, and raise many pups. Which of the three graphs shown in Part G best represents the growth of this coyote population?

Graph B

Suppose you are a researcher who is advocating for expanding restoration efforts across Hawaii. You want to highlight the positive impact of habitat restoration on native birds in the Hakalau Forest NWR. Compare the population trends between Hakalau Forest NWR and the other regions. Based on the data shown here, what conclusion would you present to stakeholders?

Hakalau Forest NWR is the only region where all populations of native bird species are either increasing or stable, highlighting the critical role that habitat restoration plays in the protection and recovery of native birds.

Prior to habitat restoration, much of Hawaii's native forest had been cleared for cattle ranching, while invasive plants and feral pigs degraded the remaining forest. Restoration within the Hakalau Forest NWR sought to remove the invasive plants, providing room for stands of native trees to become established, and put fences in place to keep out cattle and pigs. For biologists, this provided an opportunity to study the impact of restoration on bird fauna. The study lasted for 21 years following the establishment of the refuge in 1986. During this time researchers monitored the density of bird species in three test areas: (1) a middle elevation forest that had been heavily grazed, (2) an upper elevation pasture that was reforested during the study, and (3) a lower area of relatively intact forest that was formerly lightly grazed. Based on these graphs, which species of bird saw the largest increase in its population between 1987 and 2007?

Hawai'i 'Amakihi

Read the following scenario and answer the question(s) below. In 1906, President Theodore Roosevelt created the Grand Canyon National Game Preserve on the Kaibab Plateau in northern Arizona. Between 1907 and 1923, cattle grazing was greatly reduced, mule deer hunting was eliminated, and predators were killed. Over 800 cougars, 20 wolves (most had already been killed in the 1800s), and 7000 coyotes were trapped or shot. In response, the mule deer herd began to increase: By 1915, deer numbers were estimated at 25,000; 50,000 by 1920; and 100,000 by 1923. Which of the following is likely to be a direct or indirect effect of removing top predators from an ecosystem such as the Kaibab Plateau?

NOT a decrease in the carrying capacity of their prey

The barrier between the fruit fly populations ________.

NOT caused completely different mutations to occur in the two populations

Which of the following is considered a community?

several interacting species living in the same area

Which of the following best represents the overall growth rate of a population?

(birth rate - death rate) + (immigration rate - emigration rate)

Which of the following is true?

Commercial insecticides used to be more effective at eliminating bedbugs.

Adaptive radiation is rapid, branching speciation under conditions in which there is little ___________.

Competition

Assuming the populations of fruit flies are the same size, the length of time necessary for significant divergence to take place in the populations depends on ________.

the kinds of mutations in the populations and the similarity of the two isolated habitats

The y-axis to the right represents ___________.

the level of resources available per capita

According to the graph the percent transmission of UV-B relative to light intensity at the water's surface:

Decreases with increasing depth.

__________ is the number of individuals in a population per unit area.

Population density

Which of the following would best represent a clumped population dispersion pattern?

a pod of 40 migrating gray whales in the Bering Sea

If a population had a carrying capacity of 1000 individuals, which of the following populations would be experiencing the greatest rate of growth as a percentage of the current population size?

a population of 10 individuals

The different finch species found on the Galápagos Islands probably arose as a result of _____.

adaptive radiation

Oyster populations are primarily, if not exclusively, composed of _____.

adults

One example of artificial selection is ________.

broccoli, cauliflower, cabbage, and brussels sprouts bred from Brassica oleracea

An ecosystem ________.

encompasses all the organisms and the physical and chemical environment within an area

A uniform distribution will occur when __________.

individuals are competing for an evenly distributed resource such as space

What does the orange graph line represent?

logistic growth

A niche specialist is ________.

more likely to go extinct than a niche generalist

Territoriality generally results in what kind of population distribution?

Uniform

Which of the following statements are true of a population at carrying capacity? Select all that apply.

-The population growth rate equals zero. -The birth rate equals the death rate. -The rate at which resources are used is equal to the rate at which they are supplied.

If the UV-B radiation at the surface has an intensity of 0.27 watts/m2, approximately what is the intensity at a depth of 100 cm?

0.07 watts/m2

Part A - Scientific method: Testing a hypothesis A population's life history consists of its schedule of reproduction and survival, including age at first reproduction, number of offspring, frequency of reproduction, and amount of parental care. In birds, clutch size (the number of eggs per brood) is an important life history trait, and variation in clutch size is the subject of extensive ecological research.Eastern bluebirds are small songbirds that are widespread across eastern North America. Bluebirds nest in natural tree cavities such as abandoned woodpecker holes or in nest boxes provided by bird lovers.Eastern bluebird females usually lay two or three clutches of 3-6 eggs each per breeding season, which is in the spring. Late-season clutches are typically smaller than early-season clutches. Clutch size also displays a geographical gradient -- larger clutches are laid at higher latitudes. What accounts for these seasonal and geographic differences in clutch size?One hypothesis -- the egg-viability hypothesis -- proposes that the variation in clutch size results from reduced viability of eggs in warm temperatures. Observations that led scientists to develop this hypothesis include:Birds typically lay one egg a day until the clutch is complete. At that time, they begin incubating all the eggs together, resulting in an equal pace of development.As long as the surrounding temperature is below 24-26°C (75.2-78.8°F) , the temperature that triggers development, the earlier-laid eggs "keep."However, when eggs are exposed for an extended period to a temperature range between the trigger temperature and the optimum incubation temperature, 36-39°C (96.8-102.2°F), development goes awry. What prediction(s) can researchers make based on the egg-viability hypothesis? Select all that apply.What prediction(s) can researchers make based on the egg-viability hypothesis? Select all that apply.

-The probability of hatching failure will be lower at higher latitudes. -The probability of hatching failure will be higher later in the spring season. -The probability of hatching failure will be higher in large clutches.

Activity: Causes of Evolutionary Change Part A Click on the diagram to start the animation. What process is illustrated by this animation?

NOT mutation HINT Gene flow is the migration of individuals or gametes

In England, dogs with large, floppy ears called hounds came into existence. These dogs were favored for hunting because of their excellent sense of smell. Which statement most accurately represents the process that produced such dog breeds from the wild-type (feral) dog?

Humans noticed dogs with large, floppy ears and a great sense of smell and wanted more like them. They then bred them with similar dogs over many generations.

Your cousin has bedbugs. Pyrethroid insecticides failed to eliminate them. Which of the following is most likely true?

NOT Aprehend will likely work to eliminate them, but only in the presence of a neonicotinoid.

Following habitat restoration in the Hakalau Forest NWR, many bird species showed evidence of stable or increasing populations. However, it is important to note that these monitoring efforts estimated populations of both native and non-native species: Native Hawaiian species: Hawai'i 'Amakihi, 'Apapane Non-native species: House Finch Why does it matter if both native and non-native species occupy the same area? Depending on circumstances, the presence of non-native bird species could hinder the success of native bird populations through competition for limited resources, like food and nesting sites. Based on the graphs in Part A, what can you conclude about the impact of the restoration on both native and non-native bird species monitored in the upper study area between 1987 and 2007?

NOT Population densities decreased for native bird species but increased for non-native bird species. HINT Monitoring data show that population densities of all non-native and native bird species increased between 1997 and 2007, suggesting that restoration efforts had a positive impact on both native and non-native bird species in the study area.

Process of Science: What Clues About Evolution Might Road Kill Provide? Part B - Scientific method: Testing hypotheses To test their hypotheses, the researchers examined the data they collected during the period of study.Using the information available to them, they assessed whether the population sizes of cliff swallows and potential scavengers living near highways had changed over time.They determined how traffic patterns on these roads had changed over time.They also measured the bodies of cliff swallows that had been killed on the roads and compared their features to the features of cliff swallows in the general population.The table below summarizes the researchers' findings. Drag the blue labels onto the table to identify the data that is relevant to each hypothesis. Then use the pink labels to indicate whether each hypothesis is supported or not supported by the data.

NOT see phone HINT The researchers' data suggest that one of the hypotheses may be supported -- traits that help individuals avoid being hit by cars may have evolved through natural selection in the cliff swallow population. Specifically, a different wing shape may make some swallows less vulnerable to being killed by cars

You are an ecologist researching divergent evolution on the Galapagos Islands. Which of the following might you be studying?

NOT the processes by which several unrelated species of birds developed flightlessness as a result of the islands lacking natural predators

Read the following scenario and answer the question(s) below. In 1906, President Theodore Roosevelt created the Grand Canyon National Game Preserve on the Kaibab Plateau in northern Arizona. Between 1907 and 1923, cattle grazing was greatly reduced, mule deer hunting was eliminated, and predators were killed. Over 800 cougars, 20 wolves (most had already been killed in the 1800s), and 7000 coyotes were trapped or shot. In response, the mule deer herd began to increase: By 1915, deer numbers were estimated at 25,000; 50,000 by 1920; and 100,000 by 1923. Which of the following describes a graph of the Kaibab deer population between 1906 and 1923?

a J-shaped upward curve with a very rapid increase

Feathers either play a role, or may have played a role, in _____.

flight gliding courtship extended hops all of these

A population is a group of ________.

individuals of a single species that live and interact in one area

Process of Science: Can Ordinary People Help Scientists Explain Patterns in Bluebird Reproduction? Part C - Experimental follow-up: Making predictions Researchers next focused on the one prediction that was not supported by their data -- Prediction #3. That prediction said that hatching failure would be higher in large clutches because the earlier eggs would have to wait longer for incubation to begin. However, the data showed a U-shaped curve with a equally high probability of hatching failure at both small and large clutch sizes.The researchers developed a hypothesis to explain this result -- small three-egg clutches were laid more often by lower-quality females. (Lower-quality females might produce lower-quality eggs or be less skilled at incubating their eggs, resulting in a higher probability of hatching failure.)How can researchers test the hypothesis that lower-quality females produce smaller clutches? Researchers can assess the quality of an Eastern bluebird female by her plumage. Specifically, it is known that high-quality bluebird females have more ornamented blue plumage.What data should the researchers collect and graph, and what result would support their hypothesis? Drag the blue labels to the graph below to indicate what data researchers should plot on the x- and y- axes. Then select the graph line that would support their hypothesis.

see phone WRONG HINTResearchers hypothesized that small three-egg clutches showed relatively high rates of hatching failure because small clutches are usually laid by lower-quality females. Lower-quality females might produce lower-quality eggs or be less skilled at incubating their eggs.To test this hypothesis, researchers would need to collect data on female quality and clutch size. In the case of bluebirds, plumage ornamentation is known to correlate with female quality. A positive correlation between plumage ornamentation and clutch size (graph line sloping up to the right) would support the researchers' hypothesis.The egg-viability hypothesis appears to explain many of the observed patterns in Eastern bluebird clutch size. However, other factors, such as female quality, may also be important.