I guess you have not heard about the Venus figurines?

https://en.wikipedia.org/wiki/Venus_figurines

You guessed wrong. Of course I heard and saw the figurine in museums with my own eyes. What's your point?

Is there a vulva too - no not yet RTFA.

People were probably not talking (or telling stories) about their dicks that much, as opposed to something like "man and woman".

FWIW, the Romans draw lots of phalluses. http://www.redorbit.com/news/science/1113411682/ancient-roma... contains many examples.

That article deserves its own thread. TIL instead of using red lights Roman brothels just carved a dick in the ground to point the way.

The Ancient Egyptians did too. I recall examples on a temple wall that illustrate decreasing virility (semen volume) as age increases.

http://www.seiglefamily.com/2008egypt/IMG_4997%20hieroglyphi...

In the tomb of Ti at Saqqara, in a mural depicting a battle, there is a hieroglyph comprising a stylised phallus entering an even more stylised vulva. It is an insult that one warrior is hurling at his enemy. Apparently it is usually translated, somewhat primly, as "Come here, you copulator"; in his Scorn: With Added Vitriol (a collection of invective across the ages), Matthew Parris prefers the earthier "Come 'ere, you fucker."

While the symbol may not be very useful for telling stories I think it should still be pretty common because it could be used for "artistic expression", demonstration of dominance, a joke or vandalism.