One of the running quarrels on this blog concerns the age of language. I think it began about 1.8 million years ago while a great many linguists and archaeologists date it, at most, as 0.1 million years ago. The main argument in favor of what I may call a recent origin is archaeological. Symbolic artifacts start showing up late in the record of human activity. That's why I was pleased when one of my regular blog readers, Vic Sarjoo, drew my attention to a letter in the latest Nature reporting the discovery of an engraving made on a shell 0.5 million years ago. The shell was likely drilled open, the mussel inside eaten, and then the shell was preserved as a tool. It was also decorated with a zig-zag pattern, or maybe the etching had some practical purpose and was not a decoration at all. Either way, it contradicts many assumptions about human evolution. The Homo group has been marking up things for a very long time. I look forward to the time we find some Oldowan tool scratched with the news, Zog made this.
A zig-zag scratched shell does not tell us much about language, but it does remind us that the arguments that language is even younger than the Homo sapiens species are based on dubious evidence.