Reading Comprehension

PT150 · S1 · P4 · Q23 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.

23.

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

  1. A raw-food diet is significantly

    Unknown Comparison

    Unknown Comparison: raw vs. normal Too Strong: significantly healthier Nothing in the passage suggests that cooked diets are healthier or that raw food is healthier. But given that we were told that modern humans can barely survive on a raw-food diet, it seems far from supportable to call that type of diet healthier.

    1% picked this

  2. Humans would not be able

    Reverses Causality

    The last two sentences of the first paragraph are suggesting a reversed timeline: 1. we figured out how to cook food 2. this meant we could now eat some foods with high caloric density more efficiently 3. this meant our bodies started selecting for efficiency in eating foods of high caloric density 4. this resulted in our bodies' being adapted to cooked, not raw, food.

    29% picked this

  3. Early humans controlled fire long

    Unknown Comparison

    Unknown Comparison: fire vs. cooking Too Strong: long before We have no way from the passage to know which came first: fire or cooking. Presumably it was fire, because how could you cook without fire. But we don't know that it was long before. Maybe shortly after we discovered fire, we started trying to cook foods. The end of the 2nd paragraph definitely makes it seem like we may have had fire (1.9 million years ago) long before we were able or inclined to boil water (100,000 years ago). But you can cook without boiling water, so we wouldn't say "when we started boiling is when we started cooking".

    7% picked this

  4. The practice of eating a

    Opposite

    "Sedentary lives" is mentioned only in the first paragraph, and only in the context of telling us that were we to try to survive on raw foods, we'd need to live in an urban environment and live a sedentary (non-active) life. This suggests that we don't have a lot of energy to burn when we're eating raw food (that's why we'd have to stay sedentary). By contrast, we are adapted to eating cooked food and aren't adapted to sedentary lifestyles. So the passage is suggesting that by eating cooked food, we were actually able to make more efficient use of foods with high caloric density (i.e. before cooking, we'd eat a high caloric density food and most of it would pass out our body without being broken down and metabolized .... with cooking, we're able to break that dense food down so that we can metabolize more of the food and thus we have more calories to burn on non-sedentary, active living). Thus, this idea seems opposed to the thrust of what we know.

    6% picked this

  5. Correct

    Empirical evidence does not yet

    Why this is right

    This is super weak language, so it's easy to support it. It would be strong language to say that empirical evidence definitively shows that early humans adapted to cooked food. If empirical evidence had already shown that, we wouldn't even be reading this passage, which is trying to convince us that it's possible that humans adapted to cooked food. Our "However" sentence in P1 says that current evidence suggests that .. Two sentences later, These points suggest that Next sentence, the widespread assumption appears to be wrong. Last sentence of P1, selection for efficiency, we suggest, led to inability to survive on raw-food. We've also got the third paragraph, which is saying that we can't even reconstruct the soft parts early humans' digestive system because they leave no fossil record. The empirical evidence we have is sparse, incomplete, and open to interpretation. That means it is not definitive proof of anything.

    Skill tested: Author Opinion · how this choice captures the passage's function is the move to repeat next time.

    58% picked this

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