Summary
Forest fragmentation happens when development cuts large forests into smaller pieces. Some animals, like white-footed mice, thrive and multiply in these conditions. These mice are the main carrier of the bacteria that cause Lyme disease, which is passed to humans by deer ticks that bite the mice. Lyme disease is a debilitating illness.
Strongly Supported Conclusions
Forest fragmentation can be beneficial for some animals.
Combatting forest fragmentation may decrease populations of white-footed mice.
Combatting forest fragmentation may lessen instances of Lyme disease among humans.
Combatting forest fragmentation can be beneficial for human health.
Combatting forest fragmentation may decrease populations of white-footed mice.
Combatting forest fragmentation may lessen instances of Lyme disease among humans.
Combatting forest fragmentation can be beneficial for human health.
A
White-footed mice are very rarely found in unfragmented forests.
This is unsupported. The stimulus only tells us that white-footed mice thrive in fragmented forests, but gives no information about their existence or wellbeing in unfragmented forests.
B
The population density for most species of small animals increases when a continuous area of forest becomes fragmented.
This is unsupported. The stimulus only speaks to the population density of white-footed mice in fragmented forests. It gives no information about the population-density of any other species of small animals.
C
Forest fragmentation reduces the number and variety of animal species that an area can support.
This is unsupported. The stimulus does not tell us about the effects of forest fragmentation on other animal species apart from white-footed mice or on the biodiversity of an area as a whole.
D
Efforts to stop the fragmentation of forests can have a beneficial effect on human health.
This is strongly supported. Stopping forest fragmentation can decrease the population density of white-footed mice, which carry the bacteria that cause Lyme disease. Thus, it can have a beneficial effect on human health by reducing the risk of Lyme disease.
E
Deer ticks reach their highest population densities in small forest patches.
This is unsupported. We are told that white-footed mice reach their highest population densities in small forest patches. The only thing we know about deer ticks is that they can transmit Lyme disease.
Summarize Argument
The author argues that adding bike lanes to roads will not make cyclists safer because more bike accidents tend to happen on roads with bike lanes than on those without.
Identify and Describe Flaw
This is a correlation-causation fallacy. The argument overlooks the likelihood that roads with bike lanes have more cyclists, which could naturally explain the higher number of accidents without indicating that the bike lanes fail to make cyclists safer. In fact, there could be far fewer cyclists using the roads without lanes precisely because those roads are less safe.
A
overlooks the possibility that injuries sustained by bicyclists in accidents on roads with bicycle lanes are as serious, on average, as those sustained by bicyclists in accidents on roads without such lanes
This possibility is not a problem for the conclusion. Injuries being just as serious when bike lanes are present would provide yet another reason to believe that the lanes won’t improve safety.
B
fails to address the possibility that there are more bicyclists riding on roads with bicycle lanes than there are riding on roads without such lanes
This describes how the argument fails to consider that more accidents may be occurring on roads with bike lanes simply because there are more cyclists on those roads.
C
takes for granted that any road alteration that enhances the safety of bicyclists also enhances the safety of motorists
The argument never mentions motorist safety; the conclusion is about the safety of cyclists.
D
concludes that adding bicycle lanes to roads will fail to enhance the safety of bicyclists on the grounds that only some roads that currently have such lanes are safe
The argument cites a correlation between bike lanes and accidents as support; it doesn’t say that only some roads with lanes are safe.
E
takes statistical evidence that fails to support a conclusion concerning the safety of bicyclists as evidence that proves the opposite conclusion
The argument never opposes any other conclusion; it just assumes that a correlation between roads with lanes and accidents indicates that the lanes don’t enhance safety.
Cookie Cutters
64.1.13
57.3.18
55.3.09
39.2.05
25.4.24
Summary
Over the last few decades, public outcries against pollution caused stricter emissions regulations.
These regulations caused greatly improved air quality in the cities that had the most polluted air 30 years ago.
These regulations caused greatly improved air quality in the cities that had the most polluted air 30 years ago.
Very Strongly Supported Conclusions
Public outcries contributed to greatly improved air quality in the cities that had the most polluted air 30 years ago.
A
In the city with the worst air pollution today, the air quality is better than it was 30 years ago.
Unsupported. We only know that the air quality is better in the cities that had the most polluted air 30 years ago. We don’t know anything about the city with the worst air pollution today.
B
No city has worse air pollution today than it did 30 years ago.
Unsupported. We only know that the air quality is better in the cities that had the most polluted air 30 years ago. There might be some other cities in which air quality has gotten worse.
C
Most of the public outcries against pollution came from people in the cities that had the most polluted air.
Unsupported. The cities that had the most polluted air greatly improved, but this doesn’t necessarily mean that most of the public outcries came from people in those cities.
D
The most polluted cities today are not the cities that were the most polluted 30 years ago.
Unsupported. The air quality is better in the cities that were the most polluted 30 years ago, but these cities could still be the most polluted cities today.
E
Public criticism led to an improvement in the air quality of the cities that had the most polluted air 30 years ago.
Very strongly supported. Public criticism led to stricter emissions regulations, and those regulations led to improved air quality in cities that had the most polluted air 30 years ago. So, public criticism led to this improvement.
Summarize Argument: Counter-Position
The editorialist claims that unauthorized music-sharing services are not responsible for depriving musicians of their deserved earnings because other parties also take a cut of the musicians’ earnings.
Identify and Describe Flaw
The argument is flawed because it only shows that other parties (record companies, publishers, managers, etc.) are also responsible for taking money from musicians, but never actually absolves unauthorized sharing services of blame. It’s still entirely possible that these sharing services, like the other parties mentioned, are robbing musicians.
A
concludes that one party is not blameworthy merely because another party is blameworthy
This describes how the argument fails to prove that sharing services are not responsible for taking musicians’ earnings, but instead only provides evidence that others are responsible as well.
B
attempts to promote a particular behavior simply by showing that many people engage in that behavior
The argument does not attempt to promote any behavior; it only claims that these sharing services are not responsible for taking musicians’ earnings.
C
attacks a position based solely on the character of the people who hold that position
The argument never makes a personal attack on the character of the professional musicians in question. It mistakenly points to other guilty parties in an attempt to absolve music-sharing services of responsibility.
D
tries to show that a position is false simply by pointing out an undesirable consequence of holding that position
The argument does not point to any consequence of believing that music-sharing services rob musicians of royalties; it only claims that those services are not to blame.
E
treats a necessary condition for blameworthiness as though it were a sufficient condition for blameworthiness
The argument does not establish any requirement for being blameworthy. Further, the argument claims that what these services do is not sufficient to consider them blameworthy.