During the first 140 million years of existence on earth, mammals were

Question

During the first 140 million years of existence on earth, mammals were relatively small, ranging from 2 to 22 pounds, but once the dinosaurs became extinct, mammals grew in size up to 1,000 times bigger and as large as 17 tons. Once the herbivorous dinosaurs were gone the mammals no longer needed to compete for space to roam and vegetation for food. They could eat all the food they wanted, and the larger mammals were better able to fend off predators. This is why we have our hippopotamuses and giraffes of today.

If the statements above are true, which one of the following must also be true on the basis of them?

(A) If the dinosaurs had lived longer, mammals today would be much smaller yet still herbivorous.

(B) If the hippopotamus we know today was a 1,000 times smaller, other mammals would also be significantly smaller.

(C) If other larger nonmammals had survived the event that made the dinosaurs extinct, modern mammals may have been much smaller due to competition for resources.

(D) If mammals had been larger during the time of the dinosaurs, the resulting competition would have made both extinct.

(E) If hippopotamuses and giraffes had evolved as carnivores and not herbivores, large mammals most likely would not have competed with the dinosaurs for space and food.

Bunuel · Accepted Answer

OFFICIAL EXPLANATION

Answer: C

STEP 1: Read the question and identify your task.

This is a Deduction question. It asks you to find a statement that must be true on the basis of the given statements.

STEP 2: Read the argument with your task in mind. 
The argument gives you a paleontological discussion concerning the survival of large mammals like the hippopotamuses and giraffes after the extinction of the dinosaurs.

STEP 3: Know what you’re looking for. 
The correct answer will most likely be a conclusion you can come to based on how such survival occurred, mainly the competition for living space and food.

STEP 4: Read every word of every answer choice. 
Answer A tries to relate a later timing of extinction to the smaller size of the surviving mammals, but nothing in the argument leads you to believe there is a relationship between the two, only that when it happened their size changed. The only thing you can assume is that the increase in size would have been delayed. With regard to answer B, the statements give no size relationship between the large mammals like the hippopotamus and other mammals. It tells only of large mammals and how they grew in size. Answer C is a very good option for your question. The statements discuss how the large mammals grew in size because they no longer had to compete for space and food with dinosaurs. Thus, you can assume that if larger nonmammals had survived the extinction event, they would have been competitors for space and food and the larger mammals would have been smaller. Answer D may be true, but nothing in the statements leads you to believe that the size of the dinosaurs had anything to do with their extinction. Answer E states something that cannot be verified by the statements. It is possible they would have competed with carnivorous dinosaurs and the same evolutionary process would have occurred. Answer C is the correct choice.

VerbalBot · Answer

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During the first 140 million years of existence on earth, mammals were

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During the first 140 million years of existence on earth, mammals were

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