STUMPERS LX

BEFORE AND AFTER
Credit: Will Shortz
NPR Weekend Edition Sunday Puzzle
August 31, 2014

Think of a word that means "to come before." Replace its last letter with two new letters to get a new word meaning "someone who comes after you." These two words are unrelated etymologically.

HINT:
The two new letters are OR.

Answer:

The words are PREDATE and PREDATOR.