The problem with all this is that all the female character is saying is that she is bitter that today's new paleontologists are only into it because it is cool (or was, 15 years ago...) and that she was into it before it was cool. The pun is supposed to be that when they were not popular ("underground") they were also literally underground. And that only makes if paleontology is no longer about digging up bones (false, as far as I know) or if the Jurassic Park mania were still going on (certainly not the case). So it all adds up to basically just a tired and lame pun, and it's that kind of pun that gives the others a bad name.
I don't like Randall acting like he's an expert on all sorts of random fields. Obviously he can make plenty of computer science references because that's his thing but to get into details of paleontology seems kind of pretentious to me.
Also, while I respect the stick-figure style randall uses, it gets weird when you can't tell anything about a character - in this case, the characters' ages. Obviously they are older, but the kids they are complaining about look exactly the same in the comic.