Shark bites man. 50 million years ago

I thought there was something odd about this ad in an old comic book.
(1976, so don't send money.)
Then I realized it would be hard for a shark to be a man eater 50
million years ago. No men then. Plenty of sharks, but no men.
Unless.....they were time traveling, man eating sharks (with frickin
laser beams attached to their heads)! So keep an eye out.