Question 6
willacethis wrote:
Why is option D wrong in question 6?
I understand that option D does not use the logic that Walter used to derive his conclusion. However, as in case of CR, isn't a new information eligible to weaken a conclusion?
In this question, the new information would be Option D (The environment of east Africa at the time australopithecines lived there is found to have been far more varied than is currently thought)
This question is NOT asking, "Which of the answer choices, if true, most weakens Walker's conclusion?"
The question asks us what
can be inferred.So when answering this question, we are not assuming each choice to be true and then asking if that choice would weaken the conclusion.
We are identifying which choice would call Walker's conclusion into question, based on information in the passage itself.
Walker's conclusion is that
australopithecines were frugivores. Here's how Walker reaches the conclusion in paragraph one:
- The tooth micro-wear characteristics of east African australopithecine specimens are indistinguishable from those of chimpanzees and orangutans.
- Chimpanzees and orangutans are commonly assumed to be frugivorous primates.
- Therefore, australopithecines were frugivores.
willacethis wrote:
Now, since the passage suggests that new environment can result in variation in tooth micro-wear patterns, why does option D not weaken Walker's conclusion that "australopithecines were frugivores (fruit eaters)" which is based upon his observation regarding the tooth micro-wear characteristics of east African australopithecine.
What if east African australopithecine not chosen by Walker for his observation have different micro-wear patterns, indicating to a different conclusion about their diets?
OjhaShishir wrote:
(ii) How the answer to #6 is C and not B? The passage says "the diets of current omnivorous primates vary considerably depending on the environments that different groups within a primate species inhabit". So, if micro-wear patterns of australopithecine teeth from regions other than east Africa are analyzed, those micro-wear patterns are likely to be very different from the patterns that Walker found (in East Africa), thereby calling into question Walker's conclusions.
Here's choice (C):
Quote:
(C) Orangutans are found to have a much broader diet than is currently recognized.
We keep (C) because it directly undermines Walker's logic, as stated in the passage. If orangutans were, in fact, NOT solely frugivorous, but in fact ate a much broader range of foods, then Walker's basis for comparing micro-wear in orangutans to micro-wear in East African australopithecines would be harder to accept.
And here's choice (B):
Quote:
(B) The micro-wear patterns of australopithecine teeth from regions other than east Africa are analyzed.
(B) doesn't tell us anything about what these new micro-wear patterns would show us. Maybe they'd be different from patterns from within east Africa. Maybe they'd be exactly the same. The choice alone doesn't gives us this information, so it doesn't call into question Walker's conclusion about what australopithecines ate.
OjhaShishir claims that "if micro-wear patterns of australopithecine teeth from regions other than east Africa are analyzed, those micro-wear patterns are likely to be very different from the patterns that Walker found (in East Africa)." And both of you refer to this statement, later in the passage:
"In addition, the diets of current omnivorous primates vary considerably depending on the environments that different groups within a primate species inhabit"
The portion quoted only pertains to
current omnivorous primates, NOT the long-extinct australopithecines.
Here's where the author actually describes australopithecines:
"if australopithecines were omnivores too, we might expect to find considerable population variation in their tooth micro-wear patterns."
This entire statement is speculation ("IF australopithecines WERE OMNIVORES, we MIGHT EXPECT..."). Even within that speculation, there is no information about variation based on geographic location.
(B) does not directly address the argument that we're trying to call into question, while (C) does. That's why we keep (C) and eliminate (B).
I hope this helps!
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