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mastodon

by anksm22 » Fri Jul 18, 2014 11:28 pm
Either food scarcity or excessive hunting can threaten a population of animals. If the groupfaces food scarcity,individuals in the groupwill reach reproductive maturity later than otherwise. If the group faces excessive hunting,individuals that reach reproductive maturity earlier will come to predominate. Therefore, it should be possible to determine whether prehistoric mastodons became extinct because of food scarcity or human hunting, since thereare fossilized mastodon remains from both before and after mastodon populations declined, and__.

(A) there are more fossilized mastodon remains from the period before mastodon populations began to
decline than from after that period
(8) the average age at which mastodons from a given period reached reproductive maturity can be
established from their fossilized remains
(e) it can be accurately estimated from fossilized remains when mastodons became extinct
(D) it is not known when humans first began hunting mastodons
(E) climate changes may have gradually reduced thefood avai lable to mastodons



Please the question as well as the options

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by [email protected] » Sat Jul 19, 2014 6:36 pm
Hi anksm22,

This is an example of a fill-in-the-blank inference question. We need to understand the logic presented in the prompt and then find an answer that logically completes the last sentence. These types of inference questions can sometimes be tricky.

The Facts:
-Food scarcity or excessive hunting can threaten a population of animals
-Food scarcity: individuals will reach reproductive maturity LATER than OTHERWISE
-Excessive Hunting: individuals who reach reproductive maturity EARLIER will come to predominate.

The Conclusion:
-It should be possible to determine whether mastodons became extinct because of FOOD SCARCITY OR HUMAN HUNTING, since there are fossil remains from before and after mastodon populations declined and ______

The Logic: There appear to be 2 causes that can impact reproductive maturity (food scarcity - leads to LATER maturity; excessive hunting - leads to EARLIER maturity). But earlier or later THAN WHAT? The prompt doesn't establish what the "normal" time is. The prompt concludes that there should be a way to figure out whether mastodons were victims of food scarcity or human hunting though, so I'd be looking for an answer that establishes the "normal" age of maturity of the mastodon. That way, having the fossils will allow us to figure out if they matured earlier or later than normal.

Answer B completes the logic with the piece that we need.

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by VivianKerr » Tue Jul 22, 2014 12:05 am
Complete the Passage questions are the easiest questions to identify, because they end with a blank followed by a variation on the question, "Which of the following most logically completes the passage?" The blank can represent any number of different parts of an argument:

"¢ Conclusion
"¢ Assumption
"¢ Additional Evidence to Strengthen
"¢ Additional Evidence to Weaken
"¢ Inference

The skills you already have from practicing Strengthen, Weaken, Conclusion, Assumption, and Inference questions will help you get these correct. The only unique aspect is the format - the logic you need for these questions is the same. This was all excellently demonstrated by Rich! :-)
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