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RC Question

According to a theory advanced by researcher Paul Martin, the wave of species extinctions that occurred in North America about 11,000 years ago, at the end of the Pleistocene era, can be directly attributed to the arrival of humans, i.e., the Paleoindians, who were ancestors of modern Native Americans. However, anthropologist Shepard Krech points out that large animal species vanished even in areas where there is no evidence to demonstrate that Paleoindians hunted them. Nor were extinctions confined to large animals: small animals, plants, and insects disappeared, presumably not all through human consumption. Krech also contradicts Martin’s exclusion of climatic change as an explanation by asserting that widespread climatic change did indeed occur at the end of the Pleistocene. Still, Krech attributes secondary if not primary responsibility for the extinctions to the Paleoindians, arguing that humans have produced local extinctions elsewhere. But, according to historian Richard White, even the attribution of secondary responsibility may not be supported by the evidence. White observes that Martin’s thesis depends on coinciding dates for the arrival of humans and the decline of large animal species, and Krech, though aware that the dates are controversial, does not challenge them; yet recent archaeological discoveries are providing evidence that the date of human arrival was much earlier than 11,000 years ago.

Q3: Which of the following, if true, would most weaken Krech’s objections to Martin’s theory?

(A) Further studies showing that the climatic change that occurred at the end of the Pleistocene era was even more severe and widespread than was previously believed
(B) New discoveries indicating that Paleoindians made use of the small animals, plants, and insects that became extinct - Confusing answer choice
© Additional evidence indicating that widespread climatic change occurred not only at the end of the Pleistocene era but also in previous and subsequent eras – Confusing answer
(D) Researchers’ discoveries that many more species became extinct in North America at the end of the Pleistocene era than was previously believed
(E) New discoveries establishing that both the arrival of humans in North America and the wave of Pleistocene extinctions took place much earlier than 11,000 years ago

【My question】

For the above question, both options B and C look promising. Finally I chose C over B but the answer in OG is B. How did you eliminate C?

The following is what I see this passage:

Martin’s theory: 1. Cause of extinction- Arrival of humans (paleoindians) 2. Excluded climate change as an explanation of extinction(stated by Krech in later sentance).

Krech’s objection to Martin: 1. Not only large animals but also small animals, plants and insects vanished- not through human consumption 2. Climate change indeed is the primary cause of extinction.

I thought option C most weakens Krech’s theory. Climatic change occurred before and after but species didn’t become extinct. This indicates that climatic change is not a strong reason for species extinction during Pleistocene era. Hence it weakens Krech’s idea.

Option B weakens Krech’s theory too but in a less degree since Krech didn’t completely denied the role human played in the extinction of animals.

Please advice. Thank you.

Best regards,
Fuhe(Helia) Jin

Good that you start to use Zeyu’s reading method to read and find out the logical tree of the passage. But some improvements can be made:

Martin’s theory: 1. Cause of extinction- Arrival of humans (paleoindians) 2. Excluded climate change as an explanation of extinction(stated by Krech in later sentance). - Perfect summary

Krech’s objection to Martin:
(1) in areas where there is no evidence of human hunting, large animal species vanished - No Cause, but there is effect, breaking the causal relationship
(2) Not only large animals but also small animals, plants and insects vanished- not through human consumption - The same, no cause (no human consumption) but there is effect
(3) Attention: Krech only say climate change is one of the explanations to the extinction - "Climate change indeed is the primary cause of extinction" is your own assumption and never mentioned in the passage

Once you recognize this, you know clearly why B is weakening Krech - it changes “no cause but there is effect” to “there is cause and there is effect”

C is NOT the answer as explained - Krech never said that climatic change was the only/primary factor for the extinction.

Aha!! Thank you, Zeyu老师. Your answer is very helpful.