Nutritionist: Contrary to popular belief, a high-calcium diet does not prevent osteoporosis (decrease in bone density). Rather, a low-protein diet with an abundance of fruits and vegetables and a minimum quantity of meat and dairy products is essential for the prevention of the condition. Weight-bearing exercise, such as walking or climbing stairs, is also essential, since bones thicken when they withstand regular resistance.

Summarize Argument

The nutritionist claims—with no support—that a high-calcium diet doesn’t prevent osteoporosis but a low-protein, low-meat, low-dairy, high-fruit-and-vegetable diet is essential for preventing it. She also claims that weight-bearing exercise is essential for the prevention of osteoporosis, and cites support: regular resistance causes bones to thicken.

Notable Assumptions

The nutritionist assumes weight-bearing exercise provides regular resistance not provided by non-weight-bearing exercise. Every incorrect answer will strengthen that assumption or offer support for her other claims—that a high-calcium diet doesn’t prevent osteoporosis, and that a low-protein, low-meat, low-dairy, high-fruit-and-vegetable diet is essential for preventing osteoporosis.

A
Astronauts who have lived in the weightless environment of space have exhibited decreases in bone density despite vigorous physical activity.

This supports the nutritionist’s assumption that weight-bearing exercise offers more regular resistance than non-weight-bearing exercise. It points out a group that exercised in a non-weight-bearing way and suffered high rates of osteoporosis.

B
Certain medical therapies that do not involve special diets can be effective means of preventing osteoporosis.

This implies a low-meat-and-dairy, high-fruit-and-vegetable diet isn’t actually necessary for preventing osteoporosis. It casts doubt on the nutritionist’s claim that such a diet is essential.

C
Populations in countries with the lowest per capita rates of protein consumption have some of the lowest incidences of osteoporosis.

This supports the nutritionist’s claim that low-protein diets are essential for preventing osteoporosis by pointing out a correlation between low protein intake and low rates of osteoporosis.

D
Arctic peoples, who consume large amounts of calcium, exhibit one of the highest rates of osteoporosis in the world.

This supports the nutritionist’s claim that high-calcium diets are not essential for preventing osteoporosis by pointing out a counterexample: one population with both high calcium consumption and high rates of osteoporosis.

E
The incidence of osteoporosis is unusually low among strict vegetarians with low-protein diets.

This supports the nutritionist’s claim that low-protein, low-meat diets are essential for preventing osteoporosis by pointing to an example: low-protein vegetarians, who suffer osteoporosis at low rates.


25 comments

In an island nature preserve, Common Eider nests are found in roughly equal numbers in highly concealing woody vegetation, wooden boxes, and open grasslands that do not conceal nests. Some Common Eiders lay their eggs in nests established by other Common Eiders, probably in order to locate them in an area that is maximally safe from predation. Although one would expect the nests concealed in woody vegetation to be most commonly selected by other females for laying their eggs, the female Common Eiders that lay their eggs in other birds’ nests most commonly select established nests in wooden boxes.

"Surprising" Phenomenon
Common Eiders lay the eggs in the wooden-box nests rather than the woody-vegetation nests.

Objective
The right answer will be a hypothesis that explains a key difference between the wooden-box nests and the woody-vegetation nests. That difference will result in the wooden-box nests being more attractive to Common Eiders for egg-laying purposes, for some reason other than maximal protection from predators.

A
Some Common Eiders that lay their eggs in nests established by other Common Eiders have been observed, in subsequent years, building nests of their own in the nature preserve.
We don’t care what the Common Eiders did years later. We need to know why they’re choosing nests that aren’t maximally-protected from predation.
B
Established nests concealed in woody vegetation are difficult for Common Eiders to detect.
Common Eiders choose the wooden-box nests because they’re the best-protected option they can find. Woody-vegetation nests are difficult to detect, so Common Eiders choose the next-best option.
C
Defensive behavior by nest builders can sometimes deter intruding Common Eiders.
For this to work, we would need to know that woody-vegetation nest builders are more defensive than wooden-box nest builders. We don’t know that.
D
Virtually all of the island nature preserve consists of habitats that have been, at some point in the past, altered by humans.
The stimulus doesn’t tell us that human alteration makes a difference. Besides, we need something that differentiates the wooden-box nests from the woody-vegetation nests.
E
Foxes and other natural predators of the Common Eider are not uncommon in the island nature preserve.
If predators are common, why aren’t Common Eider choosing the best-protected nests? This simply intensifies part of the paradox in the stimulus.

9 comments

Xavier: The new fast-food place on 10th Street is out of business already. I’m not surprised. It had no indoor seating, and few people want to sit outside and breathe exhaust fumes while they eat.

Miranda: The bank should have realized that with all the fast-food places on 10th Street, one lacking indoor seating was likely to fail. So it was irresponsible of them to lend the money for it.

Speaker 1 Summary
Xavier thinks it’s unsurprising that the new fast-food place is kaput. How did he see this coming? Well, there was no indoor seating, and sitting outside breathing exhaust isn’t a popular option.

Speaker 2 Summary
Miranda thinks that it was irresponsible for the bank to lend start-up capital for this new restaurant. Why? Because the bank should also have foreseen the restaurant’s failure, by realizing that the lack of indoor seating was a serious problem.

Objective
We’re looking for a point of agreement. Xavier and Miranda agree the failure of this fast-food restaurant was unsurprising; it was predictable, given the lack of indoor seating, that the new place would likely fail.

A
few people want to sit outside while they eat
Neither Xavier nor Miranda expresses an opinion on this point. Neither one says anything about sitting outside being unpopular in general—even Xavier is only saying that it’s unpopular in the specific context of this one restaurant.
B
banks should not finance restaurants lacking indoor seating
Neither speaker expresses this broad opinion. Xavier never mentions banks, much less what they should or shouldn’t do. Miranda does talk about banks, but doesn’t go as far as saying that banks shouldn’t finance any restaurant without indoor seating, just this one restaurant.
C
if the new fast-food place had indoor seating, it probably would have been successful
Neither speaker expresses an opinion on this. Neither Xavier nor Miranda mentions the quality of the food or really anything about the restaurant other than its lack of indoor seating. Maybe there were other reasons it would have failed—we don’t know.
D
a fast-food place on 10th Street is likely to fail if it has any outdoor seating
Neither speaker expresses an opinion. For one, Miranda never discusses outdoor seating as a poor choice. She just believes it was unwise to provide no indoor seating. Maybe a restaurant with both options would have been fine.
E
the new fast-food place on 10th Street was a risky venture
Xavier and Miranda both agree with this. Xavier says that the restaurant’s failure was unsurprising, and Miranda says that the bank should have seen that the restaurant was likely to fail. When failure is likely, that’s equivalent to “risky.”

50 comments