"Surprising" Phenomenon
Parasites in a stingray are not good for the stingray’s health, but the absence of parasites in a stingray is an indicator that the ecosystem the stingray lives in is under environmental stress.
Objective
The right answer will be a hypothesis that reconciles the seemingly contradictory ideas in the stimulus. It will explain how the presence of parasites in a stingray can be an indication of the stingray’s sub-optimal health while the absence of parasites in a stingray can indicate an ecosystem is of sub-optimal health.
A
During part of their life cycles, the parasites of stingrays require as hosts shrimp or oysters, which are environmentally vulnerable organisms.
This helps reconcile the discrepancy. The absence of parasites in a stingray may indicate that, at the necessary point in their life cycles, the parasites could not find a shrimp or oyster to host them, as these potential hosts were adversely affected by environmental stress.
B
A stingray is a free-ranging predator that feeds on smaller organisms but has few predators itself.
This does not offer information about parasites, which are a key feature of the discrepancy.
C
A parasite drains part of the vitality of its host by drawing nourishment from the host.
The stimulus already says that stingrays with parasites are less healthy than they would be without parasites. The discrepancy involves the absence of parasites in stingrays indicating an environmentally stressed ecosystem, which (C) does not discuss.
D
An ecosystem can be considered stressed if only a few species of very simple organisms can live there.
(D) discusses what could cause an ecosystem to be considered stressed. However, it does not provide new information that reconciles the discrepancy. The stimulus also specifically addresses ecosystems under environmental stress, rather than simply being considered stressed.
E
Since the life of parasites depends on that of their host, they need to live without killing their host or else to reproduce and infect other individuals before their own host dies.
This provides insight into the life of parasites, but not into the discrepancy discussed in the stimulus. (E) does not offer information that explains how parasites can be unhealthy for jellyfish but, when absent in jellyfish, indicate an environmentally stressed ecosystem.
"Surprising" Phenomenon
Why are researchers warning that widespread use of the antidote could be dangerous, even though it has no serious side effects and is currently effective at limiting chicken pox?
Objective
The correct answer should tell us some negative effect of widespread use of the antidote. If we don’t have any negative effect from widespread use of the antidote, it will be difficult to explain why researchers are calling its widespread use dangerous.
A
The drug is extremely expensive and would be difficult to make widely available.
The fact that the drug will be difficult to apply widely doesn’t tell me why its widespread use would be dangerous.
B
The drug has to be administered several times a day, so patient compliance is likely to be low.
Unlikelihood of patient compliance doesn’t tell us why widespread use would be dangerous. Maybe patients wouldn’t get the full benefit; that doesn’t make the antidote dangerous if widely used.
C
The drug does not prevent the spread of chicken pox from one person to another, even when the drug eventually cures the disease in the first person.
But if the drug cures the disease in an individual person, why would widespread use be dangerous? We could just cure the disease in many individual people with widespread use.
D
When misused by taking larger-than-prescribed doses, the drug can be fatal.
Risk of overdose is present even when use isn’t widespread. There’s no reason widespread use would increase any particular individual’s chance of an overdose.
E
Use of the drug contributes to the development of deadlier forms of chicken pox that are resistant to the drug.
As the drug is used by and more people, the risk of more resistant, deadlier forms of chicken pox becomes greater. This helps connect how widely the antidote is used with danger, unlike (D).
Summarize Argument: Phenomenon-Hypothesis
The author presents the hypothesis that garbage dumps don’t harm wildlife. This hypothesis is supported by observations of baboons in the Masai-Mara game reserve : baboons who scavenge in the reserve’s garbage dumps grow faster and have more offspring than baboons who don’t eat garbage.
Notable Assumptions
The author assumes that eating garbage is not causing other harms to the baboons who scavenge in dumps. In other words, the author assumes that growth speed and number of offspring accurately represent the baboons’ health.
The author also assumes that there’s no alternative explanation for the differences between the baboons who eat garbage and the baboons who do not.
Finally, the author assumes that, even if the Masai-Mara baboons aren’t harmed by garbage, observations of these baboons can support a conclusion about wildlife in general.
The author also assumes that there’s no alternative explanation for the differences between the baboons who eat garbage and the baboons who do not.
Finally, the author assumes that, even if the Masai-Mara baboons aren’t harmed by garbage, observations of these baboons can support a conclusion about wildlife in general.
A
The baboons that feed on the garbage dump are of a different species from those that do not.
This weakens the argument, because it proposes an alternative explanation for the differences between the scavenging and non-scavenging baboons. If we can’t accurately compare the impact of garbage between these groups, the argument is weakened.
B
The life expectancy of baboons that eat garbage is significantly lower than that of baboons that do not eat garbage.
Like (C) and (E), this weakens the argument by adding a new way that eating garbage could harm the baboons’ health. If the scavenging baboons grow faster and have more offspring, but also die faster, it becomes much harder to say that garbage does not harm them.
C
The cholesterol level of garbage-eating baboons is dangerously higher than that of baboons that do not eat garbage.
Like (B) and (E), this weakens the argument by giving us another example of how garbage could be harming the baboons. This rebuts the author’s assumption that growth speed and birth rates are the only relevant markers of the baboons’ health, thus weakening.
D
The population of hyenas that live near unregulated garbage landfills north of the reserve has doubled in the last two years.
This does not weaken the argument. If these garbage dumps are helping the hyena population grow, that may even strengthen by demonstrating another species that isn’t harmed. Even if not, this doesn’t give us any reason to doubt the argument, so does not weaken.
E
The rate of birth defects for the baboon population on the reserve has doubled since the first landfills were opened.
Like (B) and (C), this weakens the argument by demonstrating a harm possibly caused by the garbage dumps that the author has overlooked. This harm isn’t just to the scavenging baboons, but the timing relative to the dumps opening suggests a possible causal link, thus weakening.
Summarize Argument
The author concludes that psychologists who claim empathy is the best way, in theory, to understand someone else are wrong. He concludes this by arguing that since it’s impossible to gain a direct and complete grasp of another person’s motivations, there’d be no way to achieve understanding according to the psychologists, and since one can understand people, the psychologists are wrong.
Identify and Describe Flaw
The author reasons that if the psychologists are right, we can’t achieve understanding. However, this reasoning is flawed because the psychologists didn’t argue that deep empathy is the only way to understand people, only that it’s the best way. Also, the author’s reasoning that the psychologists are wrong is flawed. Just because the theoretically best way to do something wouldn’t work in practice, it doesn’t mean it’s not the theoretically best way.
A
fails to adequately define the key phrase “deep empathy”
The term “deep empathy” is defined right after it’s first mentioned.
B
assumes something that it later denies, resulting in a contradiction
The author erroneously assumes that the psychologists’ claim is contradictory to fact. However, the author never denies this assumption.
C
confuses a theoretically best way of accomplishing something with the only way of accomplishing it
This flaw is committed. The author reasons that if the psychologists are right, understanding can’t be achieved. However, the psychologists never argued that deep empathy is the only way to understand people. They only argued that it’s the best way.
D
accepts a claim on mere authority, without requiring sufficient justification
The author doesn’t accept any claims on mere authority. The author argues that the psychologists’ claim is incorrect.
E
fails to consider that other psychologists may disagree with the psychologists cited
The author’s argument isn’t concerned with other psychologists. The author only argues that the psychologists who claim that deep empathy is the best way to understand another person are wrong.