Science can’t write a catchy melody for you, but it can advise you to include more references to sex in your songs if you want to reach the top of the charts. This advice comes from a 2011 study in Evolutionary Psychology by Dawn Hobbs and Gordon Gallup, who found that songs that made it onto the Billboard Top Ten in 2009 were far more likely to include references to sex (or, in the dry academic parlance of our times, “reproductive messages”) than songs that didn’t. Oh yes, there’s a chart:

(Study via Eric Barker.)