Q21

[ZarkaS555]

I was caught between choices A and C. I initially thought of C as correct because it seemed as more of an obvious answer given that that is how the word "typo" is used colloquially. But remembering the tricks the LSAT writers play, I thought A was a better fit because the paragraph later says that "these mutations allow the immune system to test out the different defenses until it finds one that does the job." That, to me, sounds like they do not try to adapt but instead look keep looking for the best fit. I understand now that there is no mention of other mutations but was thrown off. Help!

[ohthatpatrick]

There’s not a lot of context to help out here. Before looking at answer choices, I asked myself, “Why DID the author use the word ‘typo’, in quotes?”

When I pictured that word choice, it seemed like the author was saying “typo” in quotes, because we’re talking about genes replicating, not an actual human trying his/her best to copy something over and messing up.

I was actually tempted by (E) at first, because it seemed like the author was just using ‘typo’ as a metaphor for a flawed copy of someone’s DNA.

But (E) mentions “textual ANALYSIS”, and we’re just talking about replicating text, not analyzing it.

The problem with (A) is this distinction between adaptive and non-adaptive mutations.

Mutations aren’t inherently adaptive or non-adaptive. Every mutation is a typo. The reproductive success of the organisms with certain mutations are what later lead us to call an mutation adaptive or not, but whether it leads to reproductive success or not is a historical accident, not something baked into the mutation.

Unfortunately, there’s not a lot of context there; this is just from my knowing the basic concepts behind evolution. Both adaptive and non-adaptive mutations begin with a “typo”, since that’s what a mutation is.

So even though (C) seems boring, it’s very safe. Meanwhile, (A) has a part we can’t justify in the text.

As (almost) always, the more conservative, more supportable claim wins. Hope this helps.

[NatalieC941]

I struggled with this question because I thought that this "typo" was a positive for the immune system because it demonstrated the ability to change and allowed the RNA to "test out different defenses until it finds the one that does the job."

Therefore, when C says, "instance of imperfect copying" I initially eliminated it because I had thought that "imperfect" had a negative connotation, and moreover, this mutation was something deliberate to help it adapts and defend itself.

Then again, I have absolutely no background in any science, so I struggled to understand the passage in general...

[ohthatpatrick]

Just because a mistake works out positively doesn't mean you can't still call it a mistake to begin with.

In terms of your sense of how evolution works, you want to guard against ever thinking this way:
Therefore, when C says, "instance of imperfect copying" I initially eliminated it because I had thought that "imperfect" had a negative connotation, and moreover, this mutation was something deliberate to help it adapts and defend itself.


Mutations are random. Through the process of natural selection, seemingly "smart, wise" choices seem to emerge, but they're emerging through the randomness of mutation.

If I were testing every possible code on the way to cracking the combination of 3784, I might have intended to test 3774, and accidentally typed in 3784 instead.

That "mistake" would end up giving me some success, but that doesn't mean it was deliberate.