1. Here's why people cheat in relationships

    All happy relationships are the same, but each unhappy relationship is unique in its own way.
    David Silverman / Getty

    Genghis Khan married his wife when he was 16 and together they had four kids.

    Today, geneticists estimate that 16 million men in Asia (that's 1 out of every 200) are*
    direct descendants of Khan

    Now, I'm not saying Khan ...