Logical Reasoning

PT149 · S3 · Q10 The prehistoric fish Tiktaalik

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The prehistoric fish Tiktaalik is the earliest known animal with fingers.

Statements

TikTok (sorry, can we just call it that?) was the first fingered animal.

But having fingers wouldn't have made TikTok stand out as a weirdo, because there were so many variations in species that every fish had some wacky adaptation.

However, TikTok's fingers were probably a very important step in animal evolution because later land animals that had fingers probably trace back to TikTok.

Evaluate

Did we see anything Conditional, Causal, Math-y, or Comparative?

We saw some comparative language (and we had a Pivot). TikTok was different in the sense that he had fingers but similar in the sense that he had some unusual variation to him.

There's something vaguely causal in the last sentence that makes it seem like TikTok is causally linked to the evolution of fingers in many land animals.

Goal

This seems like one where I would have little to no idea what they want us to say, so we'll just read it a second time and then go to the answers, being wary of strong language, new concepts, or unknown comparisons.

10.

The statements above, if true, most strongly support which one of the following?

Tiktaalik likely used its fingers
Out of Scope: move on land
We don't know what function the fingers served for TikTok. The fact that land animals later (may have) evolved from TikTok doesn't mean that T used its fish fingers to move on land.
19% picked this
Tiktaalik’s fingers were its only
Too Strong
Too Strong: only Only Thing Mentioned ≠ Only Thing We only heard about T's fingers having an influence on land animals, but that doesn't mean that T's fingers were its only influence on land animals.
6% picked this
Tiktaalik is not the ancestor
Too Strong
Too Strong: not any Only Thing Mentioned ≠ Only Thing We only heard about T being an ancestor of many land animals, but that doesn't mean that T was only an ancestor of many land animals.
4% picked this
No fish without fingers would
Too Strong: no fish / ever able
We have no idea if T's fingers were ever used to help it move on land, so we can't even say that fingers would be useful for moving on land. This goes way farther than that -- not only does it assume fingers are useful for moving on land but it also assumes that nothing else would allow a fish to move on land.
6% picked this
Correct
The evolutionary significance of Tiktaalik
Why this is right
We're going to pick this mainly through elimination, since the other answers were bringing up new ideas (using fingers to move on land?) and using really extreme language. This is very soft language: "you could not determine Jenny's value as a person just through comparing her LSAT score to those of others". The opposite of this claim would be strong: "you CAN determine X just through looking at Y". The support for this answer comes from the fact that TikTok and his fingers are important, in the grand scale of evolutionary significance, but if you had seen T back its day, you wouldn't have known is was going to be special. Since there was so much variation among fish species in T's time, scientists in that era (had humans existed then) would have had no idea which of these 1000 variations they were looking at would end up being important. It defies common sense to think that ALL those variations would end up being very significant. And since you couldn't really see that T was special, compared to its peers, you wouldn't have been able to just look at it and say, "Man, that fish is going to have a done of evolutionary significance!"
Skill tested: Most Supported · how this choice captures the argument's function is the move to repeat next time.
66% picked this

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