"Surprising" Phenomenon
Why has the number of deer in North America increased significantly since the 1960s, even though the total amount of deer killed by hunters has not increased, the number of natural predators of deer has increased, and suburbs are increasingly overlapping with deer habitats?
Objective
The correct answer should tell us something different between the 1960s and today that might lead to more deer today. The correct answer can’t just minimize the effect of natural predators or the encroaching suburbs, because that wouldn’t explain an increase in deer population.
A
Pesticides that adversely affected most wildlife living in North America have been banned since the 1970s.
Something has changed since the 1960s that’s beneficial for deer. Deer may have been harmed by pesticides in the 1960s. Today, there’s reason to think they’re not harmed by those pesticides. This is the only answer that tells us something might be better for deer today.
B
Recently, attempts have been made in various parts of North America to protect deer habitats from suburban development.
This might suggest that encroachment on deer habitats isn’t as significant as it theoretically could be. But that doesn’t explain an increase in deer population. We’d still expect a decrease because of the encroachment and the increase in predators.
C
The number of deer hunters in North America has decreased since the 1960s.
The stimulus already tells us the total number of deer killed by hunters is the same. So, the number of deer hunters doesn’t matter. Even if there are fewer deer hunters, that would just mean each deer hunter is killing more deer.
D
Much of the increase in the population of wolves is due to wolves born in captivity and released into the wild.
The origin of the increased wolf population doesn’t help explain an increase in the deer population. Even if you assume these formerly captive wolves aren’t as good hunters as wild wolves, we’d still expect an increase in wolves to contribute to a decrease in deer population.
E
The greater the number of deer, the more likely they are to be afflicted with problems such as famine and disease.
This tells us something negative about greater numbers of dear. This makes it harder to explain why the deer population has increased.
Summary
Sexual reproduction occurs when the gamete of a male and the gamete of a female unite and form a genetically unique cell.
Each gamete contributes equally to the genetic material in nucleus of the new cell.
The genetic material in the cytoplasm of the new cell comes exclusively from the female’s gamete.
GM62 is genetic material found only in the cytoplasm.
Notable Valid Inferences
GM62 comes from the female’s gamete.
A
All female organisms contribute GM62 to their offspring.
This could be false. We know that GM62 can only come from female organisms, but we don’t know that all female organisms contribute GM62 to their offspring. Coming from a female organism is a necessary, not sufficient, condition for contributing GM62.
B
Only female organisms can contribute GM62 to their offspring.
This must be true. We know that only female organisms can contribute GM62 because only female organisms contribute the genetic material in the cytoplasm, and GM62 is found only in the cytoplasm.
C
Genetic material is evenly divided between the nucleus and the cytoplasm of a new cell.
This could be false. We have no information to indicate the breakdown of genetic information between the cytoplasm and the nucleus.
D
The role of the male gamete in sexual reproduction is less important than the role of the female gamete.
This could be false. The stimulus does not provide any information about relative importance of different gametes.
E
It is likely that other types of genetic material that are contributed exclusively by the male gamete will be identified.
This could be false. The stimulus does not provide any information to indicate what kinds of genetic material will be identified in the future.
Summarize Argument: Counter-Position
It’s not surprising to say that animals can use tools because all animals use them. If an animal uses something outside its body to help it do something, the animal is using a tool. For example, birds use twigs as tools to build nests, fish use mud as a tool to hide from predators, and squirrels use buildings as tools to move quickly between trees.
Identify Argument Part
The stimulus text refers to the argument's main conclusion: It’s not surprising to say that animals can use tools.
A
It provides evidence that the animals’ activities given as examples are purposeful.
The stimulus text is the argument’s main conclusion. It does not provide evidence for any other statement in the argument. Additionally, the stimulus does not offer evidence that the animals’ activities given as examples are purposeful, so no statement fulfills that role.
B
It is the conclusion of the argument.
This describes the role of the stimulus text in the overall argument. The author provides context about an announcement that biologists frequently make, concludes that the announcement is unsurprising, and then spends the rest of the stimulus explaining why it is unsurprising.
C
It is an assumption used by the argument to justify acceptance of a broader conception of what a tool is than that usually accepted by the biologists.
The stimulus text is the argument’s main conclusion. It is not an assumption—an unstated premise—of the argument. As the main conclusion, all the other statements in the stimulus support it; it doesn’t support or justify any other statement in the stimulus.
D
It calls into question the basis of the biologists’ conception of a tool.
The stimulus text is the argument’s main conclusion, stating that the biologists’ announcements are “unsurprising.” It does not question the biologists’ definition of a tool; it simply notes that many animals use tools.
E
It addresses a weakness in the biologists’ announcements that stems from their ambiguous use of the word “external.”
The stimulus text is the argument’s main conclusion, which simply states that the biologists’ announcements are “unsurprising.” The stimulus does not argue that the announcements are weak or that the biologists use “external” ambiguously.
Summarize Argument
The politician concludes that a democratic society should not control its citizens’ personal appearance. This is supported by the claims that personal appearance is a way for citizens to express themselves and potentially make political statements. This makes appearance similar to the free verbal expression upon which democratic societies rely.
Describe Method of Reasoning
The politician describes an accepted attitude toward one case and draws an analogy to another case with comparable features to reason that a similar attitude should apply to the latter case. By presenting personal appearance as analogous to free speech because both allow expression, the politician argues that democratic societies should not control personal appearance, just as they should not control speech.
A
argue for a conclusion by suggesting that the opposite conclusion leads to an absurdity
The politician does not discuss the implications of the opposite conclusion to the one reached in the argument. The argument is presented directly, without discussing counter-arguments.
B
reach a general conclusion based on the absence of clear counterexamples to an empirical thesis
The politician does not reach a general conclusion at all, only a conclusion about the specific case of personal appearance in a democracy. Also, there’s no empirical thesis here which could lack counterexamples.
C
support a conclusion by claiming that it is widely accepted
The politician does not claim that the conclusion drawn in the argument is widely accepted. The only widely accepted attitude which the politician cites is about an analogous case used to support the conclusion.
D
reach a conclusion based on evidence that is similar to evidence commonly thought to support an analogous case
The politician concludes that personal appearance should be free in a democratic society based on evidence that personal appearance is a form of self-expression, and self-expression is commonly thought to support the analogous case of verbal free speech.
E
reach a conclusion about what democratically governed societies actually do based on premises about what democratically governed societies should do
The politician doesn’t make a conclusion about what democratic societies actually do, only about what they should do.
Summarize Argument
The author concludes that in the future, TV advertisers would be more effective by targeting over-65 consumers, rather than 18-to-25 consumers. This is because the average discretionary income of those over 65 will soon be greater than that of people who are 18-to-25.
Notable Assumptions
The author assumes that there aren’t other factors relating to over-65 consumers that might offset the significance of their higher discretionary income. What if, for example, people over 65 tend to spend less money on purchases than people 18-to-25, despite having a higher average discretionary income?
A
Consumers over the age of 65 tend to watch different television shows than do young adults.
This only means TV advertisers would need to change which shows they advertise on. But this doesn’t suggest targeting the over-65 consumers might not be better than targeting the 18-to-25 group.
B
The older a consumer is, the more likely he or she is to have already established brand loyalties.
This points out that, compared to the 18-to-25 group, the over-65 group is less susceptible to advertising designed to create brand loyalties. So, even though the older group might have more money to spend, it may be more difficult to change their minds about what brand to buy.
C
The average discretionary income of young adults is projected to rise in the near future.
The premise already establishes that the average discretionary income of those over 65 will soon be greater than that of young adults. So, even if young adults’ income will go up, we still know it will be lower than the over-65’s income.
D
The greater a consumer’s discretionary income, the more likely advertising is to encourage that consumer to buy.
This strengthens the argument by establishing a connection between higher discretionary income and potential effectiveness of ads.
E
The number of consumers over the age of 65 is increasing more rapidly than is the number of young adults.
This strengthens the argument by ruling out the possiblity that the number of over-65 people is significantly lower than the number of 18-to-25 people, which could have been a factor weighing against targeting the over-65 group.