Santa Clara island is home to a large population of wild horses, but

Question

Santa Clara island is home to a large population of wild horses, but horses are not native to the island. It is known that Spanish settlers colonized Santa Clara island and lived there continuously from 1650 to 1740, and the bones of horses were recently found in an excavation site that can be dated to the early 1700s. Therefore it is likely that the Spanish settlers were the ones who introduced horses to Santa Clara island.

The answer to which of the following questions would be most useful in evaluating the validity of the conclusion drawn above?

A. Did the Spanish settlers introduce horses to any other islands near Santa Clara?
B. Have any excavations found evidence of human settlers who lived on Santa Clara prior to 1650?
C. Were any other nonnative species introduced to Santa Clara island by the Spanish settlers?
D. Have any human settlements remained on Santa Clara island since 1740?
E. Does Santa Clara island contain any horse bones that can be dated to before 1650?

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dhart · Answer

Does Santa Clara island contain horse bones , that can be dtaed before 1650 ? option E

quosaperiam · Answer

Hi quaeneque, I also think E is correct. My reasoning is that if horse bones dated before 1650 were found, horses must have been on the island before the Spanish settlers arrived, so the conclusion would be weakened.

Do you think E is better than B because it directly proves the presence of horses before 1650, while B only proves that other people may have lived there?

Vivek1707 · Answer

A Even if the Spanish brought horses to nearby islands, that doesn't prove they were the ones who brought them to Santa Clara.
B. Out of scope: Finding earlier settlers it doesn't tell us whether horses were already on the island before the Spanish arrived.
C. Whether the Spanish introduced other nonnative species doesn't really help answer who introduced the horses.
D. What happened after 1740 isn't relevant. The question is who first brought the horses to the island.
E. Correct This gets right to the heart of the argument. If horse bones dating before 1650 are found, the Spanish couldn't have introduced them. If no such bones exist, the conclusion becomes much more convincing.

dhart · Answer

Yes , B only rpoves that other ppl lived there , whereas E points out presense of bone fossils before 1650 which makes the argument strong i think

egmat · Answer

Hi quosaperiam,

Yes, your instinct is exactly right, and let me sharpen the  why  so the difference between E and B is airtight.

The conclusion is a  causal claim : the Spanish settlers (there  1650 - 1740 ) are the ones who  introduced  the horses. To evaluate that, we need a question whose answer can either confirm or break the link "settlers - horses."

Why E works

"Does Santa Clara contain horse bones that can be dated to  before 1650 ?" hits the causal link head-on.

-  Yes  - horses were already there before the settlers arrived - settlers did  not  introduce them - conclusion collapses.
-  No  - nothing predates the settlers, so they remain the best candidate - conclusion holds.

Either answer moves the argument. That's what "most useful in evaluating" means.

Why B doesn't do the job

"Have any excavations found evidence of human settlers who lived on Santa Clara  prior to 1650 ?" is about  people , not  horses . Suppose the answer is "yes, earlier people lived there" - so what? Those earlier people may or may not have brought horses. It leaves the horse question completely open, so it can't confirm or break the causal link. It's a classic  true-but-irrelevant  distractor: interesting, but it never touches whether horses were present before the settlers.

So you're spot on: E is better precisely because it speaks directly to the  presence of horses  before  1650 , while B only raises the possibility of  other people  - which by itself proves nothing about horses.

Quick way to lock it in

Watch how B changes if we turn one knob:

- As written ("human settlers prior to  1650 ") - irrelevant to horses.
- If it read "...evidence of  horses brought by  settlers prior to  1650 " -  now  it would matter, because it finally touches the animal in question.

That one edit is the whole difference: the useful question must act on the  horses , not just on  people .

Answer: E

Bunuel · Answer

Veritas Prep Official Explanation

1) Horses are not native to the island (so someone had to introduce them)

and

2) Evidence exists that ties horses to the island during the time that the Spanish settlers were there

The question then really is: were the horses already there when the Spanish got there (so someone else introduced them) or did the Spanish bring them there?

Choice E helps to answer that directly: if horses were there before the Spanish got there, then the answer is no, the Spanish did not introduce the horses. Therefore, choice E is correct.

Choices A and C are similar in that they attempt to bring in correlation: other islands, and other species. But since the evidence in the argument is directly tied to the timeline, choice E this the argument head on, and an answer of "yes" to E can completely ruin the argument. With A and C, neither answer (yes or no) can either prove or destroy the argument.

Choice B has a similar problem: sure, the existence of people prior to the Spanish raises the likelihood that someone else may have introduced the horses, but this answer cannot provide direct proof either way: note that the question doesn't even ask "were there other people" but rather "has evidence been found of other people."

Choice D attacks the timeline but in the wrong way: we already have evidence of horses during the Spanish settlement, so establishing whether any people came and stayed after that does not help us date the introduction of horses.

Santa Clara island is home to a large population of wild horses, but

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Santa Clara island is home to a large population of wild horses, but

Prep Toolkit

615 to 715 in 15 Days (Ria's Strategies)

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My Rewards