Reading Comprehension

PT150 · S1 · P4 · Q21 Evolutionary Implications of Cooking

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It might reasonably have been expected that the adoption of cooking by early humans would not have led to any changes in human digestive anatomy.

Topic

Evolutionary effects on humans of cooking

Framework

Old / New

Main Point

People used to think that humans' use of cooking probably didn't have any effect on digestive anatomy, but now we think we've evolved so much to having a cooked diet (our teeth, jaws, and possibly intestines) that we'd be unable to survive in most cases on a raw food diet.

Summary

FIRST PARAGRAPH

- It might reasonably have been expected that X. After all, Y. However, current evidence suggests ...

These rhetorical features warn us about what the passage will likely be doing. We open with an allusion to Old beliefs, or Typical beliefs, or usual assumptions, and then we get our Author's (but / yet / however / recently) Pivot right after that.

Upon reading the first sentence, we should already be pausing and saying to ourselves,

And we'd be right. That's essentially the main point right there.

From the "However" until the end of the first paragraph, we're getting the current evidence for the fact that cooking has changed us: - we wouldn't be able to live off raw food (except under special circumstances) - this suggests we've now evolved to a form that requires cooked food - there has actually been plenty of time (on an evolutionary scale) for these changes to take place, since we have evidence that cooking started over 250,000 years ago.

The author crystallizes her takeaways at the end of the first paragraph, saying

Because we could cook, we were able to eat a diet with more high caloric density food. Because we were able to eat that type of food, our bodies adapted ways to optimize eating that type of diet, and now we're so adapted to a cooked diet that we'd struggle to live on a raw diet.

SECOND PARAGRAPH

The topic sentence here indicates that this paragraph will be discussing questions about how we've changed, to be more adapted to a cooked diet. - there's a known change in the fossil record to our tooth and jaw size around 100,000 years ago. - the author thinks that was the restul of adapting to cooked food. - she thinks it's possible that cooking started over 1 million years ago and some adaptations occurred then, but then the adaptations seen around 100,00 years ago were ones that happened when we invented the concept of boiling water.

THIRD PARAGRAPH

Since this paragraph begins by saying , it looks like this paragraph still falls under the framing idea at the beginning of the 2nd paragraph: important questions therefore arise

We know that our guts are different from those of other great apes. Some people think it's because we eat more raw meat than apes do. This author thinks that "adaptations to cooking" could just as easily explain it.

She suggests a future research direction in the final sentence, to help determine which hypothesis is more likely.

21.

The authors would be most likely to agree with which one of the following statements?

Correct
Small teeth and jaws limit
Why this is right
This is pretty Main Point - adjacent. The main point was that "the adoption of cooking has led to evolutionary changes to our anatomy, such that now we are adapted to cooked food and cannot survive on raw food". Oh, yeah? What changes to our anatomy? "Well, tooth and jaw size have decreased, and maybe some stuff with the digestive system." So this answer might be pretty intuitively appealing from our understanding of the gist of the passage. Otherwise, we would find supporting text in the first two sentences of the 2nd paragraph. ... what limits the ability of humans to utilize raw food. The principal effect of cooking considered to date has been a reduction in tooth and jaw size.
Skill tested: Author Opinion · how this choice captures the passage's function is the move to repeat next time.
86% picked this
Because of its reliance on
Out of Scope: reliance on plants
All we know about Homo ergaster is that during its evolution about 1.9 million years ago, its tooth and jaw size reduced. We have no idea whether it relied on plants in its diet. We have no idea what its intestinal volume is. It should feel very trappy in the Word Salad way we see that this answer is tossing together a character from the 2nd paragraph with wording (intestinal volume) from the 3rd paragraph.
1% picked this
Early humans did not utilize
Too Strong: did not
Nothing in this passage is drawing a harsh, absolute line like, "Prior to point X, humans never used plants for food". The passage is saying that once we adopted cooking and then evolution changed us anatomically over thousands of thousands of years, we have now gotten to the point where we would struggle to survive on an uncooked diet, because much raw plant food has low digestibility. That's all we hear about plants, and that's miles away from saying, "Humans didn't eat plants until we started cooking".
1% picked this
The properties of the human
Too Strong: primarily Contradicted, if anything
In the final paragraph it says that "human digestive anatomy differs from that of other great apes in ways that have traditionally been explained as adaptations to a high raw-meat diet". That sentence is saying the differences between our digestive anatomy and that of other great apes has traditionally thought to be primarily the result of a high raw-meat diet. But this answer is saying "the properties of our digestive anatomy (overall) are primarily the result of adapting to high-meat diet". But more importantly, the authors don't buy into that hypothesis. They say that these differences "may therefore be at least as well explained by the adoption of cooking as by eating raw meat".
9% picked this
The human digestive anatomy has
Too Strong
Too Strong: changed little Opposite, if anything Since the central thesis of this passage is that the adoption of cooking has led to significant anatomical changes over evolutionary time, it would seem to go counter to the thesis to say "human digestive anatomy has changed little over evolutionary time". The final paragraph is saying it's very hard for us to figure out how the digestive anatomy has changed because soft stuff like intestines and colons don't leave fossils that we can see thousands or millions of years later. But the authors would presumably believe that changes have occurred.
2% picked this

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