Logical Reasoning

PT143 · S4 · Q8 The giant Chicxulub crater

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The giant Chicxulub crater in Mexico provides indisputable evidence that a huge asteroid, about six miles across, struck Earth around the time many of the last dinosaur species were becoming extinct.

Conclusion

The big asteroid that hit Chicxulub was probably not responsible for most of the final dinosaur extinctions.

Evidence

Major asteroid impacts kill a lot of stuff near the impact site, but there's not much evidence they'd have a worldwide effect. In fact, there have even been bigger asteroids hitting Earth, when there weren't any contemporaneous extinctions.

Evaluate

Given That asteroid strikes aren't known to have worldwide effect (just to kill animals locally) How Could We Argue That the big asteroid that hit Chicx was responsible for most of the final dinosaur extinctions?

Hmmm, maybe the remaining dinosaurs were all having some sort of Burning Man in that area of Mexico? They got together for a party and so the asteroid was able to wipe them all out at once?

Maybe even though there's little evidence for a worldwide effect, there's enough of a local or regional effect to kill off the dinosaurs?

Maybe it does something to their food supply?

Goal

Look for an answer that allows to make a causal story in which this asteroid strike leads to the extinction of most of the remaining dinosaurs.

Which one of the following, if true, would most weaken the argument?

The vast majority of dinosaur
Too Weak
This feels like more than nothing. If there aren't that many dino species left to kill, then it's easier for an asteroid to kill off most of the remaining. But we still need to know that most of the remaining ones were congregating near the impact site, or else we haven't really escaped the author's "local, not global extinctions" argument.
4% picked this
The size of a crater
No Impact
Ha ^ (pun intended?) We need a storyline that sells us on the idea that this asteroid was a dino-killer, and this is a wishy-washy physics statement about all asteroids.
2% picked this
Fossils have been discovered of
Too Weak
This certainly explicitly reads as "dino-killer", but the author was never denying that many dinosaurs would have been killed by the impact. He's just saying that global extinctions wouldn't be attributable to the impact. This answer is consistent with the author's argument, since the fossils might all belong to dinosaurs that lived in that area. This answer doesn't say that "a number of dinosaurs went extinct".
17% picked this
There is no evidence that
No Impact
Okay, pun also intended, but it's less fun the second time. No one is expecting a 2nd big asteroid to have hit Earth at the same time as this one. We only get hit by those asteroids once every 100 million years or so. The author is cool with this asteroid being the only one. He isn't blaming the dinosaur extinctions on other asteroid impacts. He's saying that asteroid impacts aren't the type of thing that can cause global extinctions.
4% picked this
Correct
During the period immediately before
Why this is right
Oh, my goodness, it was the "Dinosaur Burning Man" story line for real! Right before the asteroid hit, the dinosaurs had all met up for some "last dinos on earth" Fyre Fest (literally), and they were just in the wrong place at the wrong time. This answer allows us to argue how a local impact could have still led to many extinctions.
Skill tested: Weaken · how this choice captures the argument's function is the move to repeat next time.
73% picked this

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