Logical Reasoning

PT10 · S1 · Q16 A favored theory to explain

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A favored theory to explain the extinction of dinosaurs, together with many other species, has been the globally catastrophic collision of a large asteroid with the Earth.

Conclusion

The asteroid-impact theory is at least incomplete, if not false.

Evidence

There's an alternate theory for what killed the dinosaurs and many other species (volcanos, which spewed dust into the atmosphere, cooling the planet).

Evaluate

We're dealing with the "Explain Curious Fact" pattern, where the Curious Fact is the extinction of dinosaurs (and many other species), and we have two different explanations so far for what could have caused it.

CURIOUS FACT: what killed the dinos and many other species?

ASTEROID THEORY: an asteroid crashed into earth. VOLCANO THEORY: volcanos spewed dust into the atmosphere, which cooled down the planet.

The normal pressure points are Alternate Explanations for the curious fact (but usually if we already have two in consideration, they aren't going to add a third), as well as the Plausibility of the provided explanation(s).

Goal

We want an answer that helps us argue the volcanos (or some third thing) were a big part of the dino extinction, or an answer that helps us argue that the asteroid couldn't have caused the extinctions on its own.

16.

Which one of the following, if true, most strongly indicates that the asteroid-impact theory is at least incomplete, if not false?

Large concentrations of dinosaur nests
No Impact
This is an incredibly weak statement .. "at least one species congregated in large groups at least once during their life". That weak idea isn't going to have any impact on us solving whether asteroids, volcanos, or both cause all the dinosaurs to go extinct.
1% picked this
Dinosaur remains indicate that some
Unclear Impact
This somewhat helps us argue that dinosaurs wouldn't have gone extinct from the asteroid, because they could "travel to escape the local effects of certain catastrophes". But the answer only says "some" (i.e. at least one species of dinosaur) could have migrated like this. Assuming those species weren't incinerated by the asteroid on impact, they might have been able to migrate away from the area the asteroid ruined, in which case we might need some other explanation for why the migrating dinos went extinct. But this is a very sketchy story on thin legs. We don't know if "asteroid impact" even qualifies as one of the "certain catastrophes" that you can avoid by migrating away.
22% picked this
Legends from many cultures, such
No Impact
The fact that various ancient peoples learned via fossils that dinosaurs existed tells us nothing about what caused dinosaurs to go extinct: asteroid? volcanos? both? neither?
1% picked this
In the Gobi desert in
No Impact
Finding large dinosaur fossils in dry climates does not provide any information about the cause of their extinction or contradict the asteroid hypothesis.
10% picked this
Correct
The fossil record in Montana
Why this is right
This answer is making it seem like something was already killing dinosaurs before the asteroid arrived, and makes it seem like there were still dinosaurs alive after the asteroid had come. The layer of extraterrestrial dust is the calling card of the asteroid, so that layer corresponds to the year the asteroid came. This is saying before that asteroid even showed up, dinosaur species were dying off. We went from 35 species down to 13, before the asteroid arrived. So clearly the asteroid isn't telling the whole story of what was eradicating the dinosaurs. And then for bonus points, the asteroid only seems to take it from 13 species left to 5 species left, so again there must be more to the story, because something else needs to kill off those last five species.
Skill tested: Weaken · how this choice captures the argument's function is the move to repeat next time.
67% picked this

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