A recent study concludes that prehistoric

Answer choices

1. A

   Too Weak4% picked this

   Some modern warm-blooded species other than birds have been shown to have descended

   Answers with "some" are almost always wrong on Strengthen / Weaken / Paradox, since we're being asked which answer choice idea would have the most impact. This notion that "at least one modern warm-blooded species definitely descended from cold-blooded" helps Party 1 a bit, but it's just one data point, so not very compelling.

   4%
2. B

   Too Weak8% picked this

   Having growth rings is not the only physical trait of

   This one is laughably weak. This says that "cold-blooded species have at least one physical trait besides growth rings". Cool. You mean physical traits like mouths, eyes, nose? How does that help us decide anything about birds? This one wouldn't help either Party.

   8%
3. C

   Unclear Impact6% picked this

   Modern birds did not evolve from prehistoric species

   Since the argument between these two parties is about prehistoric birds, it's hard to figure out how finding out that modern birds are a completely separate thing from what they're arguing about has any effect on their conversation.

   6%
4. D

   No Impact17% picked this

   Dense blood vessels are not found in all

   If this said that "some animals with dense blood vessels aren't warm-blooded", then it would help Party 1 a bit, by undermining Party 2's support. But it says "some warm-blooded species don't have dense blood vessels". That's irrelevant to the case being made for cold-blooded as well as to the case being made for warm-blooded.

   17%
5. E

   Correct65% picked this

   In some cold-blooded species the gene that is responsible for growth rings is also responsible

   Why this is right

   This helps Party 1 a bit more than the other answers do. It still only says "at least one cold-blooded species has both growth rings and dense blood vessels". But this fact ends up being stronger than (A) or (D), since it reconciles Party 1's evidence for cold-blooded (growth rings) with Party 2's evidence against cold-blooded (dense blood vessels). It's a frustratingly weak correct answer on a weirdly structured question. We had no reason to be trying to support Party 1; that just happens to be what our best answer does. The trait of growth rings is thought to occur only in cold-blooded. The trait of dense blood vessels suggests active, which necessitates warm-blooded. So, growth rings is more tightly anchored to cold-blooded than dense blood vessels are to warm blooded. We end up strengthening Party 1, who already had a stronger case, by showing that Party 2's objection is totally compatible with the cold-blooded hypothesis.

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

   65%