I can walk into a room and create a good ambience. I was taught all about this back when I studied acting. One of the things they would teach you is how to send out positive signals when you enter a room. I am glad I learned this.
To summarize the particular song a male sings and the behavioral responses of females to song and morphological signals are not genetically inherited in a fixed manner but are determined by learning early in life.
Jewelry and pins have been worn throughout history as symbols of power sending messages. Interestingly enough it was mostly men who wore the jewelry in various times and obviously crowns were part of signals that were being sent throughout history by people of rank.
The way that organizations and organisms anticipate the future is by taking signals from the past most the time.
I'm on the Sensa diet. It's a little magic powder based on Dr. Hirsh's clinical trials and studies and it basically signals the brain that you're full through smellology.
The cult of the individual is killing us. I think Twitter signals the death of western civilisation but people have been saying that since Demosthenes.
If beauty isn't genius it usually signals at least a high level of animal cunning.