Thanks for thinking of me! This actually was one of several papers with implications for my thesis that came out early this year. I started a thread on this article when it appeared, but not much came of it:
From the abstract:
Our observations provide support for an account of the Blombos and Diepkloof engravings as decorations and as socially transmitted cultural traditions. By contrast, there was no clear indication that they served as denotational symbolic signs. Our findings have broad implications for our understanding of early symbolic communication and cognition in H. sapiens.
The interesting thing about Blombos is that it coincides with the expansion of trade networks and the likely appearance of fully-modern grammar (language in the modern sense). Diepkloof shows how the engravings evolved over time, but the truly remarkable thing is how little they changed from 100 kya to 65 kya. I put some of this into the wider context of the co-evolution of brain, language, and morality in this blog post/podcast: