I was just reading about time signatures, and some question just popped into my mind: if so many time signatures are available, why is the 4/4 the "common time"? And I'm not talking about "well, because it's the most used in pop music". I know that. It is more on the "why is it 4/4 and not, say 5/4"? What makes it so catchy and appealing to be present in 99% (or whichever percentage) of popular music? You can take it as a rather philosophical question if you will. Do you think we humans have some predilection to this musical timing? Would it be ingrained in our DNA or something, or it may be related to our heartbeat or whatnot? Has anyone, for instance, come across articles or studies that show some physiological or psychological relationship between the 4/4 signature and its appeal to the average person?