Logical ReasoningDifficulty: Hard

PT158 S2 Q3 Explanation

Bovine remains found in a certain

A free, expert breakdown of this official LSAT Logical Reasoning question.

TopicsNecessary Assumption

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Stimulus

Bovine remains found in a certain region of Africa date back to a time when the climate was arid. While there were people in the region at this time, there were no other large mammals there. Any natural sources of water available to these bovines would have brought other large mammals to the people living in the region were no longer exclusively hunter-gatherers.

What this question is testing

Necessary Assumption

Conclusion

These bovines were domesticated, and the locals had graduated from the hunter-gatherer lifestyle.

Evidence

Ancient arid Africa. Bovine bones. People around, but zero other large mammals. Any natural water source would have been a large-mammal magnet. So no water means no wild large mammals — but somehow bovines were still there.

Evaluate

The detective work here is clever: no other large mammals means no natural water, yet bovines were present. Someone must have been keeping those bovines alive — and it was not the rain. But this logic only holds if bovines are the type of animal that would normally need natural water to survive. If bovines could just tough it out in the desert on their own, their presence proves nothing about domestication. The argument is quietly assuming bovines are not some sort of camel-like exception to the large-mammal water rule.

Goal

Find the answer that plugs this gap: bovines cannot make it without water in the wild, so humans must have been providing it.

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The question
3.

Which one of the following is an assumption on which the

Answer choices

  1. Correct72% picked this

    Unless they are domesticated, bovines are unlikely to exist in a region where there are no natural sources

    Why this is right

    This answer states that unless they are domesticated, bovines are unlikely to exist in a region where there are no natural sources of water. This is exactly the assumption the argument requires. The argument's logic runs: no other large mammals were present, which proves there were no natural water sources, yet bovines were present. For this to prove domestication, wild bovines must be unable to survive without natural water — otherwise, they could have been wild bovines surviving in the arid region without human help. Apply the negation test: if wild bovines could readily survive in a waterless region, the entire argument collapses, because the presence of bovines without natural water would not indicate domestication. This answer bridges the critical gap between "no natural water" and "must be domesticated."

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

  2. Too Strong, Out of Scope20% picked this

    Domesticating animals is one of the first practices that a society must adopt in order to change from

    This answer claims that domesticating animals is "one of the first practices" a society must adopt to transition from hunting and gathering to agriculture. The argument does not need anything this broad or prescriptive. The argument needs a specific link between bovines, water, and domestication — not a general theory about the stages of societal development. The argument concludes these people were no longer exclusively hunter-gatherers based on the evidence of domesticated bovines; it does not need to establish that animal domestication is a prerequisite for leaving the hunter-gatherer stage. The word "must" makes this answer far too strong — the argument would survive even if some societies transitioned to agriculture without domesticating animals first.

  3. Out of Scope3% picked this

    With the help of humans, other large mammals would have been able to inhabit

    This answer suggests that with human help, other large mammals could have inhabited the arid region. But the argument does not need to establish anything about what humans could have done with other animals. The argument's reasoning is: no other large mammals were present (fact), so there was no natural water (inference), yet bovines were present (fact), so bovines were domesticated (conclusion). Whether humans could have also helped other animals survive is irrelevant to this chain. The argument needs an assumption about why bovine presence without water implies domestication, not about the theoretical possibility of humans supporting other species.

  4. Too Strong2% picked this

    No human culture obtains food both through agriculture and through hunting

    This answer claims no human culture obtains food both through agriculture and through hunting and gathering. This is far too extreme. The argument concludes that these people were "no longer exclusively hunter-gatherers" — meaning they had added domestication to their repertoire. But the argument does not need to assume that agriculture and hunting are mutually exclusive. In fact, the conclusion's use of "exclusively" implies the opposite: these people may still have hunted and gathered but also practiced animal husbandry. The argument is perfectly compatible with cultures that combine agricultural and hunter-gatherer practices; it only claims these particular people were not limited to the latter.

  5. Irrelevant Comparison3% picked this

    Domesticated animals of a given size do not need as much water as do wild

    This answer compares the water needs of domesticated versus wild animals of the same size. While this is a factual claim about animal biology, it does not address the argument's gap. The argument needs to know whether wild bovines could survive without natural water in an arid region — not whether domesticated bovines need less water than wild ones. Even if this comparison were true, it would not explain why the presence of bovines without natural water implies domestication. The key question is whether wild bovines require the same natural water sources that would attract other large mammals, not whether the domestication process itself changes water requirements.

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