[Arkcon]

Originally posted by Kamog:
What I find interesting is, why do ALL the cicadas of the same species happen to follow the exact same 17-year life cycle? Why aren't the life cycles staggered so that each year, some of them emerge from the ground, finishing their 17-year periods? Why are they so syncronized? So at any given time, all the cicadas alive are exactly the same age!

I wonder how it all got started in the beginning.

This is common in the natural world. Randomly spaced "bumper crops" followed by low years so predators don't overwhelm the prey. Happens with acorns, cherries, and in this case Brood X {wiki}