"Surprising" Phenomenon
Many iceberg lilies are consumed by bears, yet that consumption helps the lilies survive.
Objective
Any hypothesis resolving this discrepancy must explain a mechanism by which bears eating the lilies helps the lily species survive.
A
When grizzly bears forage for iceberg lilies, they generally kill many more lilies than they eat.
It is irrelevant whether the bears eat the lilies they destroy. The lilies are killed regardless, so it remains unexplained why they benefit from the foraging.
B
Iceberg lilies produce so many offspring that, when undisturbed, they quickly deplete the resources necessary for their own survival.
This explains why the foraging bears help the iceberg lily species survive. If bears left the lilies alone, the lilies would deplete their resources and struggle accordingly.
C
A significantly smaller number of iceberg lily flowers are produced in fields where grizzly bears forage than in fields of undisturbed iceberg lilies.
This widens the discrepancy. If foraging bears reduce the number of lily flowers, then the bears make it more difficult for the lilies to reproduce.
D
The geographic regions in which iceberg lilies are most prevalent are those regions populated by grizzly bears.
This explains why many lilies are eaten by the bears, not why the lilies benefit from the bears’ foraging.
E
Iceberg lilies contain plentiful amounts of some nutrients that are necessary for grizzly bears’ survival.
This explains why bears forage for the lilies, not why the lilies benefit from that foraging.
Summarize Argument
The author concludes that sugar consumption doesn’t exacerbate hyperactivity in children with attention deficit disorder. She bases this on a study that showed no difference between children with attention deficit who ate sugar versus those who ate a sugar substitute.
Notable Assumptions
The author believes that the study shows sugar doesn’t affect hyperactivity. She must then assume that sugar substitutes don’t also exacerbate hyperactivity, or else the study would pointless. The author must also assume that sugar consumption can be divorced from the settings in which sugar is consumed. Supposing the children in the study were at Disneyland, we would expect high levels of activity across the board.
A
Only one of the three types of sugar used in the study was ever widely suspected of exacerbating hyperactivity.
We don’t know if children who ate that type of sugar were especially hyperactive.
B
The consumption of sugar actually has a calming effect on some children.
We don’t care if it’s a calming or neutral effect. We’re trying to weaken the claim that it doesn’t have a hyperactive effect.
C
The consumption of some sugar substitutes exacerbates the symptoms of hyperactivity.
It’s very possible there was no important difference between sugar and sugar substitutes in the study. If so, that totally destroys the author’s conclusion.
D
The study included some observations of each group in contexts that generally tend to make children excited and active.
“Some” qualifies what would’ve otherwise been a strong weakener. If only a small portion of the study was done in settings that make children excited and active, then the author’s takeaway from the study still stands.
E
Some children believe that they can tell the difference between the taste of sugar and that of sugar substitutes.
We don’t care if children believed they were using placebos. We care about the effect sugar had on the group that got sugar.