Q22 - Archaeologist: After the last ice

[yusangmin]

could you please explain this to me?
im sure theres some "central assumption"

but i cant gquite grasp it!

i chose A but now that i lookat it b looks good too..

if the bridge was long gone before they were made..wouldnt that be support for the fact that whoever was staying in siberia made the clovis points (and not the people who migrated back)

also..A seems kinda funky to me now cuz i thought LSAT didnt like the whole "known evidence" vs actual first date stuff....


thanks

[giladedelman]

Thanks for your question!

So, way back when, paleohumans crossed from Siberia to North America via the now-defunct Bering land bridge. Since Clovis points have been discovered in Siberia, the argument goes, Clovis points must not have been invented in North America.

Well, that's fishy. I mean, airplanes have been found in France -- does that mean they weren't invented in the United States? The argument seems to be assuming something about the age of the Siberian Clovis points: specifically, that they predate the ones found in North America.

(A) strengthens the argument by making this assumption explicit. If the Clovis points found in Siberia are older than any of the known North American ones, this supports the conclusion that they were not invented in North America. You're right that the "known" factor means that it's still possible that there are unknown North American Clovis points that would undermine the argument, but that's okay; we're looking for something that would most strengthen the argument, not something that makes the argument perfect.

(B) doesn't affect the argument either way because it doesn't help us determine which set of Clovis points is older. Maybe the bridge disappeared, then the points were invented in North America, then somebody rowed a boat full of them to Siberia -- or vice versa!

(C) is wildly out of scope.

(D) is also out of scope. We care specifically about Clovis points.

(E) would weaken the argument, if anything, by suggesting that Clovis points may have been invented in North America and then brought back to Siberia.

Does that answer your question?

[theaether]

I picked B for this one. I like the explanation for A and it makes a lot of sense. I'm just going to nitpick and say that I don't think B is completely irrelevant to the argument. It does reduce some potentially valid gaps in the argument, like NA people simply walked across the strait in the reverse direction, carrying the Clovis spears with them. Of course B, nor does any other choice, account for every possible weakness.

But now that I think again about A, doesn't it leave open the possibility that the original inventors of the Clovis could be NA, and just all emigrated to Siberia across the strait? That would leave many remnant spears that are very "old."

[timmydoeslsat]

I would like to help explain why B can be eliminated.

We all understand that A can strengthen our argument. While it is not perfect because of the "those that have been found" issue, it still gives us something.

Let us talk about the very popular wrong answer of B.

I will give a little text diagram of how we can eliminate this.

We know from the stimulus that groups of paleohumans left Siberia and went to North America using the Bering land bridge.


__NA__ **************____SIBERIA_____




XXX__NA__ ************** XXXXXX____SIBERIA_____


As you can see, those X's are indeed people, and some groups left Siberia and went to NA.

Now we will have the land bridge disappear, as what answer choice B shows happened before ANY clovis point found to date was made (same issue as A eh?)



XXX__NA__ XXXXXX____SIBERIA_____


OK, the bridge is gone. The points have not been made.

See how this does nothing to our argument in this scenario? We don't know which group of paleohumans will invent the clovis!

If you would like to show the only other possibility in which all the paleohumans left Siberia to go to NA...then you would have:


XXXXXXXXX__NA__ ____SIBERIA_____


And how does this scenario when the bridge disappears help STRENGTHEN the idea that clovis points were NOT invented in North America? This answer can be seen as neutral to our conclusion or it weakens our conclusion.

[zainrizvi]

I don't understand how (A) strengthens the argument.


Even if the points found in Sibera were older those found in North America, there is the huge possibility that people crossed over the bridge to bring them from North America to Siberia.


(B) strengthens the argument by showing that the transfer of the points was effectively cut off between the two locations. I guess it is kind of a weak strengthener though because it doesn't really compare the relative age of points. Just because they found stuff in Siberia doesn't mean that the North American ones weren't there as well.


So do we choose (A) because it is somewhat stronger than (B)? And if we do, how can you really judge the relative strengths of these arguments while doing a test? Usually if i see something strengthen I automatically choose it... this one requires comparison

[cuadk42]

I think I can break this down-

First, let's look at the argument and find the assumptions. There are two here:
1. (more obvious)- The paleohumans in question did NOT return across the bridge after inventing the Clovis points and leave them in Siberia to be found
2. (less obvious and overlooked) "groups of paleohumans who went from Siberia -> NA" are the ONLY paleohumans. There is never evidence presented that there weren't any paleohumans who stayed in Siberia.

First, the wrong answers. If you look at (E), it is tricky because it addresses the first assumption but leaves out the NOT so it actually weakens the argument. Answers (C) and (D) are out of scope.

So we are down to (A) and (B):

(B) doesn’t necessarily strengthen the argument. It states that the bridge disappeared before any of the points found to date were made. That only means, according to (B), whoever made the Clovis points in question STAYED in Siberia after making them (ie they could not migrate to NA after). While that provides valuable information about the timeline of paleohuman migration, it does NOT provide us any information about the timeline of Clovis point origin. Paleohumans could have migrated to NA, invented the points there first, then returned to Siberia, then the bridge disappeared, they made some more points, and then were stranded in Siberia.

(A), on the other hand, is MUCH stronger by providing direct information about the age of the Clovis point, rather than about the paleohuman migration. If the points found in Siberia are older than ANY of those found in NA, then that means, regardless of the migration patterns, that the Clovis point in Siberia is older than ANY North American clovis point, which means it could not have been invented there.

Of course, a flaw here is that "have been found" may exclude those that exist but have not been found, but this flaw is present in both answer choices.

Remember, they care about the age of the clovis point, and not of the migration patterns of the paleohumans. Focus on the conclusion and I think it becomes clear which answer is stronger.

[mic_a_chav87]

I guess I'm just being a stickler, but I am definitely not convinced that A) truly strengthens this argument at all. If anything, we should rationally assume that since people traveled for SI to NA on the bridge, then people could travel back to, and as many other have said, brought the spears with them.

I also see how B doesn't strengthen the argument, but I still don't like A.

I don't think any answer truly strengthens it at all, and I think that the LSAT plays on people's false assumptions similar to that exhibited in A so often, that it is intellectually dishonest for them to use a similarly faulty assumption here.

[giladedelman]

Great discussion here! I think my favorite post is by cuadk42, because it makes the point that answer (B) "does NOT provide us any information about the timeline of Clovis point origin," and ends with some fantastic advice: "Remember, they care about the age of the clovis point, and not of the migration patterns of the paleohumans. Focus on the conclusion and I think it becomes clear which answer is stronger."

This is right on the money. Our job is to strengthen the conclusion that the Clovis points were invented in Siberia, not in North America. Whether the bridge disappeared before the points were made tells us absolutely nothing about where or when they were made. So it doesn't affect the argument either way.

Now, let's be careful, guys. We've established that (A) isn't a perfect answer. But just because it doesn't make the argument totally bulletproof doesn't mean it doesn't strengthen it at all. If the Clovis points found in Siberia are older than any found in North America, this strengthens the notion that they were invented there. Yes, there are a couple of assumptions that remain, but all the answer has to do is support the conclusion even a little bit, which this one does.

Thanks for all your posts!

[theanswer21324]

I get what people are saying about why (B) is wrong, but it seems like the same reasoning can be applied to (A).

I'm more confused after reading Gilad's write-up than I was before I started. In his parallel hypothetical, airplanes were discovered in France, and that was used to mean that airplanes were not invented in America. However, if you apply (A)'s reasoning, it would be saying that the airplanes found in France are older than any of those found in America. The argument does not make any sense, and I don't see how this would strengthen the argument that the object was not invented in X. With all the talk about rowing boats, it makes maybe eve more sense that airplanes were invented in America, but they somehow got transported to France. If the points were moved after having been invented, then of course the points found in Siberia would be older than those found in North America - because they were invented in North America, got moved to Siberia, and are no longer in North America

Does anybody see this differently?

[asmaa737]

I think you must really focus on the conclusion. You must prove that they were NOT invented in North America. They MUST have invented them in Siberia (or maybe elsewhere?) first.

B states that the bridge disappeared before any known clovis point found to date was made. That could still mean they were invented separately, in North America and in Siberia. This does NOT strengthen the answer choice.

Plus, folks who have qualms with (A) because it states "to date" must also see that (B) is no better in this respect, because (B) also states "to date." This leaves open the possibility for clovis points to be invented in NA, but were not found yet. If that were the case (that they find clovis points in NA that were made before bridge disappeared), then this actually *weakens* the conclusion...

[Alvanith]

Premises:
People left Siberia to NA from a bridge that no longer exists.
Found Clovis in Siberia.
Conclusion:
Clovis was not invented in NA.

Problem: the argument basically just tells us Clovis was found in Siberia and therefore concludes that Clovis was not invented in NA, but we are not told anything about Clovis in NA! NA or Siberia which is the first place that Clovis was invented should be a comparison of the time, but here we only have one-sided evidence.

Assumption: the argument assumes no Clovis that can be dated to an earlier time is found in NA.

A strengthen the argument by providing a comparison and hitting on the assumption directly.

B does not strengthen much because it still does not provide the much needed comparison. All it can do is just to make it less likely that the Clovis was not brought by NA paleohumans before the bridge disappears, and still we need to plug in some further assumptions to make this answer plausible.

[cwolfington]

The key to this question is the phrase "contrary to popular belief..." because you can infer that Clovis points have already been discovered in North America. Thus (B) becomes irrelevant, and (A) strengthens the argument by saying that the Clovis points in Siberia are older than the ones previously found.

[economienda]

cwolfington basically hit the nail on the head

[rose.1070]

This question and correct answer choice is by far the most challenging one I have come across in my LSAT studying, and I pray that I never encounter a question like this on the October LSAT, but "A" is definitely right:

Popular Belief: Clovis points were invented in North America
Conclusion: Nope, Clovis points were not invented in North America
Why? (Premise): Because some archaeologists just found some Clovis points in Siberia

What we might be thinking as LSAT readers: Why the hell should I care that Clovis points were found in Siberia? And, more importantly, how in any way, shape, or form, does this lead to the conclusion that Clovis points were not invented in North America? Are these things mutually exclusive...surely they each could have independently invented them, right? The stimulus also mentions a land-bridge between the two areas that was commonly crossed, so couldn't they have been invented in North America and brought to Siberia via the land-bridge? Couldn't they have been invented in North America thousands of years before people even lived in Siberia (sure, it says that people crossed from Siberia to North America, but this doesn't mean people already didn't live in North America), the land-bridge disappear, and the Clovis points were spread to Siberia via Europe and Asia instead?

My View: This is a strengthening question. A valid answer might say: "Based on a million other studies, and in conjunction with the recent findings, it was found, inconclusively, that Clovis points were not invented in North America." Or maybe something like this: "The material required to make Clovis points has never existed in North America." BUT notice how these valid answers don't touch on one important piece of information, our premise! There is a relationship between our premise and our conclusion, and that is what we need to strengthen, not independently the premise or independently the conclusion. My above section raises a ton of questions as to why I should even care about this new premise. If we want to strengthen this argument, we need to add something that will make us care about this premise in the first place, because as of right now it is pretty much irrelevant information to the conclusion.

After analysis, we are down to two answer choices, A and B:

A.) This tells us that the Clovis points found in Siberia are older than those found in North America.
Why "A" sucks: People could have invented them in North America and brought all of them over to Siberia via the land bridge. There may be ones older in North America not discovered yet. They could have been invented independently from one another, so even if the Siberian ones are older, it doesn't mean they technically "invented" them.
Why "A" is right: "A" actually makes our premise relevant to the discussion. It mentions the premise explicitly, while "B" doesn't. If the ones found in Siberia are older than those found in North America, that makes us think to ourselves "well hey, then that premise links up to the conclusion a little better than before because it is possible that they were invented in Siberia and brought over to North America across the bridge." Yes, it raises a bunch of other questions, some of which I listed above, and yes, it doesn't rule out many of these potential assumptions, but it does make us care about our premise. No other answer choice does this.

B.) This tells us that the bridge disappeared before any found Clovis points were made.
Why "B" sucks: This does not make us care about our premise. At all. I actually believe this alleviates more assumptions/questions than answer choice "A" does, and therefore strengthens the conclusion better than answer choice "A" does, but I don't believe it strengthens the overall argument (i.e. the relationship between the premise and the conclusion) better than "A" does. This may very well be an acceptable answer if "A" didn't exist, because it does provide some degree of strength into the stimulus, but "A" does exist and really accomplishes what we want.

[pewals13]

If you are being tempted by the siren call of (B) you are probably assuming either that all of the Clovis points found to date are from Siberia or that Siberian Clovis points are the oldest ones found to date. I think (A)'s positioning throws this assumption into your subconscious as you hit (B).

Think about this answer choice in a vacuum. Remember, the stimulus tells you nothing about the age of the Clovis points found in Siberia, or whether any have been found in North America.

(B) The Bering land bridge disappeared before any of the Clovis points found to date were made.

Okay, so what? You have no idea where the oldest Clovis points found to date are from or where the ones from Siberia mentioned in the stimulus fit into the chronology of currently existing Clovis points that have been discovered.

If the earliest Clovis points found to date are from North America, this weakens the argument in the same way that assuming the oldest Clovis points found to date are Siberia strengthens it.

You have to assume to contents of (A) to make (B) work.

Any time you need to assume one answer to make another work--choose the former.