I have explained just above sir in case you missed
https://gre.myprepclub.com/forum/you-ma ... tml#p13511However, this sentence is part of a passage where I assume the scenario is the following
You may wonder how the expert on fossil remains is able to trace descent through teeth, which seem _________ pegs upon which to hang whole ancestries.
You may wonder how it is possible that scholars are able to figure out the WHOLE story from a simple tooth - which apparently is a flimsy, weak, almost inconsistent clue we do have.
Well, you could be surprised by a new AI technology is able to do that when we use the right amount of data...and blah blah blah
I hope now is more clear