About this video
A passage-style reasoning question about how the large stones at Tiwanaku may have been moved. Archaeologists hypothesize that reed boats carried 40-ton stones about 90 kilometers across a lake, and an experiment moved a 9-ton stone that way. The question asks which fact would best help evaluate that hypothesis, and the answer is whether the traditional reed-boat techniques were in use when Tiwanaku was inhabited.
You'll be able to
- identify what evidence would bear directly on a hypothesis.
- judge whether a proof-of-concept experiment supports a larger claim.
- eliminate answer choices that do not bear on the hypothesis.
Key words
- Hypothesis
- A proposed explanation that evidence can support or undermine.
- Proof of concept
- A small test showing that a method is possible, which does not prove it works at full scale.
- Relevant evidence
- Information whose answer would change how likely the hypothesis is.
- Reed boat
- A boat built from bundled reeds, used on the lake in the passage's hypothesis.
- Irrelevant choice
- An answer whose yes or no answer would leave the hypothesis unchanged.
Transcript
- [Narrator] The ruins of the prehistoric Bolivian city of Tiwanaku feature green andacite stones weighing up to 40 tons. These stones were quarried at Copacabana, which is across a lake and about 90 kilometers away. Archaeologists hypothesize that the stones were brought to Tiwanaku on reed boats.
To show this was possible, experimenters transported a 9-ton stone from Copacabana to Tiwanaku using a reed boat built with locally available materials and techniques traditional to the area. Which of the following would be most useful to know in order to evaluate the support for the archaeologists' hypothesis?
So which would be most useful to know? Whether the traditional techniques for building reed boats were in use at the time Tiwanaku was inhabited. Well, that seems pretty useful. These researchers, they are using traditional, techniques traditional to the area, but we don't know for sure whether they were used at the time when Tiwanaku was inhabited.
If they weren't used at the time that Tiwanaku was inhabited, well, that wouldn't be the way that the Tiwanakans, I guess, would have transported, cuz they wouldn't have had those techniques. So this one is looking pretty interesting. Let's see if we can rule out the other choices.
So would it be useful to know whether green andacite stones quarried at the time Tiwanaku was inhabited were used at any sites near Copacabana? Well, no, that wouldn't. That would be interesting, but it's completely possible that Tiwanaku was the only place. Maybe it was some type of a sacred place where they took the trouble of bringing these 40-ton stones and that wasn't really important anywhere else.
So this one doesn't seem that. This one doesn't seem like a good choice. So would it be useful in order to support the archeologists' hypothesis, would it be useful to know whether reed boats are commonly used today on the lake? Well, no, we're talking about whether folks, I'm assuming a long time ago used these reed boats at Tiwanaku, or to bring these stones to Tiwanaku.
In fact, it would be, it's interesting if reed boats are used today, but it's. It very well they could be using modern boats and it has nothing to do with whether the Tiwanakans used the reed boats. Whether the green andacite stones at Tiwanaku are the largest stones at the site.
Well, no, even if they aren't or are the largest stones at the site, it's still makes you want to ask the question, "How did these 40-ton stones get there?" So that doesn't help you think about how they got there. Whether the reed boat built for the experimenters is durable enough to remain usable for several years.
No, the Tiwanakans, they might have. Even if these reed boats weren't durable enough, maybe one boat for every crossing of the lake, just so to get one 40-ton stone across. So, this one, the durability doesn't seem to matter. I would have been curious because the researchers transported a 9-ton stone while they're talking about that there were stones weighing up to 40 tons.
It would be useful to know whether these techniques could be used to transport something that weighs 40 tons, more than the 9 tons. This is a nice proof of concept, but that wasn't the choices. And so, I do like choice A as the best answer. Whether the traditional techniques for building reed boats were even used at the time Tiwanaku was inhabited.
Cuz if they weren't used, then this hypothesis wouldn't carry a lot of weight, so to speak.
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