Though it seems obvious, your family tree doesn’t end at your great-grandparents, or even your great-great-great-great-grandparents. Everyone is the result of an unknowable number of couplings across millions of years, and trying to trace it all the way back is basically impossible.
But scientists now believe that they’ve uncovered at least a small portion of that great mystery, and it has to do with people who have blue eyes. Yeah, really.
If you’ve ever wondered how your eyes came to be so blue, then here’s your answer!