I'm writing an essay which I want to divide into 3 parts. The first will detail events from the recent past (past decade), the second will go further back in history (past century) and the third will go back many millions of years. I'd like to title these three parts something like "History", "Older History", "Even Older History", but this sounds kinda clunky.
What would be a better titling scheme that achieves this effect?