In a study of tropical forests

Answer choices

1. A

   Deepens Paradox, if anything1% picked this

   The species of trees that is most common in a forest thrives there because it is best suited

   This answer helps us understand why the most common species in the forest thrives, but we don't need any help with the backstory on why a given species is the most common. We need an answer to help us understand why the tree species that is least common lives longest. The implicit contrast this answer provides is that, "trees of the rare species are worse-suited to the local climate". That's not a reason they would survive longer. That's more like the opposite.

   1%
2. B

   Weak Impact5% picked this

   Older trees tend to reproduce the

   This seems a little tempting. We need to explain how the trees that are least common are the ones that live longest. This is connecting old age to low reproduction numbers, so the ideas are somewhere in the same vicinity. But this answer applies to all trees. All trees as they get older will reproduce less. Even these trees that are most common / reproduce the most will reproduce less when they are older. The less you reproduce, the more rare you would be as a species, but this answer isn't saying that "the species of trees with the longest life spans have the lowest reproduction rates". It's saying "older trees (of any species) reproduce less than younger trees".

   5%
3. C

   No Impact0% picked this

   The study tracked preexisting tree species but did not introduce any new species to

   We don't care about any distinction between "preexisting" and "introduced" species. Whether a species was native or nonnative to an area, if it's successful enough to be the most common / most reproducing, then we'd probably figure that it also survives longer in that ecosystem. This doesn't give us a way to explain why the rarest species of tree is also the one that lives longest.

   0%
4. D

   Effect vs. Explanation2% picked this

   The survival of the trees of the rarer species enables tropical forests to recover more

   This is telling us what ramifications there are when rarer species of trees survive. It's isn't explaining how / why the rarest species is able to survive longer than other tree species.

   2%
5. E

   Correct92% picked this

   The trees of the common species have more competition for the resources they need than do the trees

   Why this is right

   Not a great answer, but this at least helps to explain why trees of the rarest species live longer: they have less competition for resources. It's easier to thrive and survive when you have a stable food supply. Most importantly, it's the only answer choice besides (A) that points to a distinction between the common species and the rare species.

   Skill tested: Paradox · how this choice captures the argument's function is the move to repeat next time.

   92%