The prehistoric fish Tiktaalik

Answer choices

1. A

   Out of Scope: move on land18% picked this

   Tiktaalik likely used its fingers to move

   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.

   18%
2. B

   Too Strong6% picked this

   Tiktaalik’s fingers were its only feature to play a significant role in the development of

   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%
3. C

   Too Strong4% picked this

   Tiktaalik is not the ancestor of any currently surviving

   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%
4. D

   Too Strong: no fish / ever able6% picked this

   No fish without fingers would ever be able to move

   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%
5. E

   Correct67% picked this

   The evolutionary significance of Tiktaalik could not be determined just through comparison to fish species

   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.

   67%