Written language may have evolved more than once in human history. “Judging from what we know about the evolution of art all over the world, there may have been many traditions that were born, lasted for some time and then vanished,” says Jean Clottes, former director of research at the Chauvet caves in southern France. “This may be one of them, most probably not the first and certainly not the last.”

− http://www.newscientist.com/article/mg20527504.300-oldest-writing-found-on-60000yearold-eggshells.html