For some years now Simon Garrod and Nicolas Fay, among others, have been looking at the emergence of symbolic graphical symbols out of iconic ones using communication experiments which simulate repeated use of a symbol.
Garrod et al. (2007) use a ‘pictionary’ style paradigm where participants are to graphically depict one of 16 concepts without using words, so that their partner can identify it. This process is repeated to see if repeated usage would take advantage of the shared memory of the representation rather than the representation itself to the point where a iconic depiction of an item could become an arbitrary, symbolic one.
Garrod et al. (2007) showed that simple repetition is not enough to allow an arbitrary system to emerge and that feedback and interaction are required between communicators. The amount of interaction afforded to participants was shown to affect the emergence of signs due to a process of grounding. The signs that emerged from this process of interaction were shown to be arbitrary as participants not involved directly in the interaction were shown to have trouble interpreting the outcome signs.
The experimental evidence then shows that icons do indeed evolve into symbols as a consequence of the shared memory of the representation rather than the representation itself. Which is all well and good, but can this process be seen in the real world? YES!
I was talking to a friend on skype and he started typing repeated right round brackets:
At first I just thought he had some problem with keys sticking on his keyboard, but after he did it two or three times I finally asked. To which he alluded that that they were smilies. Upon further questioning, it seems that this has become a norm for Russian internet chat that their emoticons have lost their eyes - presumably in the same process as Garrod et al. (2007) showed above.
They have also created an intensification system based on this slightly more arbitrary symbol, where by the more brackets repeated the happier or sadder you are. Among those in the UK and America, the need to intensify an emoticon has stayed well within the rhealms of iconicity with : D meaning "very happy" and D: meaning "oh God, WHHHHHYYYYY". Japan have a completely different emoticon system altogether which focusses on the eyes: ^_^ meaning happy and u_u meaning sad. Some of argued that this is because in Japan people tend to look to the eyes for emotional cues, whereas Americans tend to look to the mouth, as backed up by SCIENCE.
I'd be interested to see if norms have been established in other countries, either iconic or not.
Garrod S, Fay N, Lee J, Oberlander J, & Macleod T (2007). Foundations of representation: where might graphical symbol systems come from? Cognitive science, 31 (6), 961-87 PMID: 21635324
Yuki, M., Maddux, W., & Masuda, T. (2007). Are the windows to the soul the same in the East and West? Cultural differences in using the eyes and mouth as cues to recognize emotions in Japan and the United States Journal of Experimental Social Psychology, 43 (2), 303-311 DOI: 10.1016/j.jesp.2006.02.004