Re: Sea otters in Kedrick Bay feed on sea urchins and thus keep the local
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10 Mar 2024, 08:21
Sea otters in Kedrick Bay feed on sea urchins and thus keep the local sea urchin population from growing large enough to destroy the kelp beds on which the urchins feed. Therefore, any oil spill that destroyed the sea otter population in Kedrick Bay would guarantee the destruction of the kelp beds by the urchins.
The argument's conclusion is the following:
any oil spill that destroyed the sea otter population in Kedrick Bay would guarantee the destruction of the kelp beds by the urchins
The support for the conclusion is the following fact:
Sea otters in Kedrick Bay feed on sea urchins and thus keep the local sea urchin population from growing large enough to destroy the kelp beds on which the urchins feed.
So, basically the reasoning is that, since sea otters keep the local sea urchin population from growing large enough to destroy the kelp beds, if the otters disappeared because of an oil spill, the kelp beds would for sure be destroyed.
Which of the following, if true, would most seriously call into question the reasoning in the argument above?
I'm curious to see what the answer could be because the argument is pretty convincing, and the correct answer will somehow cast doubt on the conclusion.
A. An oil spill severe enough to destroy the Kedrick Bay otter population would be likely to diminish the populations of other animal species that feed on Kedrick Bay’s sea urchins.
This choice supports rather than casts doubt on the conclusion.
After all, if an oil spill would diminish the populations of other small animal species that feed on the sea urchins, then there's even more reason to believe that, if an oil spill destroyed the sea otter population, the sea urchins would become sufficiently numerous to destroy the kelp beds.
Eliminate.
B. If the population of sea otters in Kedrick Bay declined in number as the result of an oil spill, sea otters from other locales would not soon replace them.
This choice supports rather than casts doubt on the conclusion.
After all, this choice helps to confirm that the sea urchins would become sufficiently numerous to destroy the kelp beds if an oil spill caused the sea otter population to decline by confirming that other sea otters would not show up to eat the sea urchins.
Eliminate.
C. In locales where both sea urchins and sea otters are present, sea urchins are the sea otter’s main food source.
This choice has no effect on the strength of the argument.
After all, regardless of whether sea urchins are the otters' main food source, the passage states as fact that the otters keep the sea urchin population in check by eating them.
Eliminate.
D. Because of the pattern of ocean currents in and around Kedrick Bay, there is little likelihood that even a major oil spill in the area would affect the size of the local sea otter population.
This choice misses the point and weakens the case for the wrong conclusion.
After all, the conclusion is not that it's likely that the sea otter population will be reduced by an oil spill and that, therefore, it's likely that sea otters will destroy the kelp beds.
Rather, the conclusion is about what would happen IF the sea otter population were destroyed by an oil spill.
So, this choice has no effect on the strength of the argument.
Eliminate.
E. The sea urchin population in Kedrick Bay would be likely to be harmed by any oil spill that reduced the size of the local sea otter population.
This choice weakens the argument by showing that even thought the premise is true, the conclusion may not be.
After all, even if the sea otters are keeping the sea urchin population in check, given what this choice says, the sea urchins may not become sufficiently numerous to destroy the kelp beds if an oil spill destroys the sea otter population because an oil spill will likely reduce the population of sea urchins as well.
Keep.
Correct answer: E