Logical Reasoning

PT112 · S4 · Q19 Birds need so much food energy

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Birds need so much food energy to maintain their body temperatures that some of them spend most of their time eating.

Conclusion (surely = opinion)

Given a seed eating bird and a nectar eating bird with the same overall energy requirement, the seed-eating bird should spend more time eating than does the nectar-eating bird.

Evidence (since)

A given amount of nectar provides more energy than does the same amount of seeds.

Evaluate

We're trying to judge this Comparison.

Both types of birds need the same overall amount of energy. One gets its energy from eating seeds, the other from eating nectar. A given amount of nectar provides more energy than does the same amount of seeds.

Thus, the author assumes it will take less time for the nectar-eater to get to their overall total energy amount.

There is a Missing Link assumption like,

But this argument seems more ripe for objections that the correct answer will Defend against.

Given that ... the nectar eating bird gets more energy per unit from nectar, How could we still argue that ... the nectar eating bird needs more time (or the same time) to attain its required energy?

Maybe it's harder to find nectar than it is to find seeds. Say that two kids were each trying to collect enough coins that they $10 of money. One kid collects only quarters. The other collects only dimes. Clearly, the quarter-collector gets more value per coin, but what if the dimes are plentiful and easy to grab and the quarters are sparse and hidden? The dime-collector might still get to $10 faster.

Goal

Let's look for an answer, which will probably have Defender language like "not", that is ruling out some objection that would make nectar-eaters take longer to reach their energy requirement, even though nectar is more energy rich per unit than seeds are.

19.

The argument relies on which one of the following questionable assumptions?

Birds of different species do
Too Strong
Too Strong: Generally Out of Scope: Reality vs. Hypothetical This argument is only about a hypothetical comparison between two types of birds that do have the same energy requirements. Whether that ever occurs, rarely occurs, or usually occurs in real life is totally irrelevant to judging the author's hypothetical.
4% picked this
The nectar-eating bird does not
Negation Doesn't Weaken
If we negate this and say, "the nectar-eating bird does sometimes also eat seeds", would that weaken? i.e. Would that help us argue that the nectar-eating species spends more time eating than the seed-eating bird? No, it would kind of strengthen the conclusion. If the nectar-eating bird is getting great energy from nectar and then also getting some energy from seeds, then it could hit its energy requirement in less time than the seed-eating bird, which just reinforces the conclusion.
5% picked this
Correct
The time it takes for
Why this is right
If we negate this and say, "the time it takes for a nectar-eating bird to eat a given amount of nectar does take more time than a seed-eating bird needs to eat the same amount of seeds", would that weaken? i.e. Would that help us argue that the nectar-eating species spends more time eating than the seed-eating bird? Yes! We can say, "Sure, author, a given amount of nectar has more energy in it than does the same amount of seeds, but it takes a lot longer to consume that nectar." Thus, in the end the seed-eater might get to its energy requirement sooner than the nectar-eater. Maybe seeds only provide 2 units of energy (whereas nectar provides 3 units), but if it takes a bird 5 seconds to eat a seed and 20 seconds to eat the same amount of nectar, then the seed eater can eat 4 seeds in 20 seconds (8 units of energy) in the same time that the nectar eater can eat 3 units of nectar. To go back to the analogy of quarter-collectors vs. dime-collectors trying to accrue $10, if we say that "it's takes a lot longer to find a quarter than it does to find a dime", then the dime collector has an improved chance of winning the race to $10.
Skill tested: Necessary Assumption · how this choice captures the argument's function is the move to repeat next time.
73% picked this
The seed-eating bird does not
Negation Doesn't Weaken
If we negate this and say, "the seed-eating bird does have a lower body temp than the nectar-eating bird has", would that weaken? i.e. Would that help us argue that the nectar-eating species spends more time eating than the seed-eating bird? No, it's totally irrelevant. Body temperature relates to how much energy a bird needs, but in this argument we're controlling for how much energy a bird needs. Both birds have the same overall energy requirement, so whether that comes from them having equivalent body temps, or asymmetric body temps (seed eaters need more/less than nectar eaters) it won't make any difference.
10% picked this
The overall energy requirements of
Negation Doesn't Weaken
If we negate this and say, "the overall energy requirements do depend on on other factors in addition to body temp", would that weaken? i.e. Would that help us argue that the nectar-eating species spends more time eating than the seed-eating bird? No, it's totally irrelevant, because this argument is judging a hypothetical comparison in which the two bird species have the same overall energy requirement. The backstory of how they got to that same energy requirement (whatever combo of size, habitat, body temp, etc.) makes no difference.
9% picked this

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