Earliest evidence of symbolic behavior found


December 03, 2014

Long overlooked fresh water shells lying in a museum drawer for more than a century have yielded the earliest evidence of symbolic behavior, according to an article in Nature this week..

The article is entitled “Homo erectus at Trinil on Java used shells for tool production and engraving“, by Josephine C. A. Joordens et al. The abstract of the article states:

“The manufacture of geometric engravings is generally interpreted as indicative of modern cognition and behaviour. Key questions in the debate on the origin of such behaviour are whether this innovation is restricted to Homo sapiens, and whether it has a uniquely African origin. Here we report on a fossil freshwater shell assemblage from the Hauptknochenschicht (‘main bone layer’) of Trinil (Java, Indonesia), the type locality of Homo erectus discovered by Eugène Dubois in 1891. In the Dubois collection (in the Naturalis museum, Leiden, The Netherlands) we found evidence for freshwater shellfish consumption by hominins, one unambiguous shell tool, and a shell with a geometric engraving. We dated sediment contained in the shells with 40Ar/39Ar and luminescence dating methods, obtaining a maximum age of 0.54 ± 0.10 million years and a minimum age of 0.43 ± 0.05 million years. This implies that the Trinil Hauptknochenschicht is younger than previously estimated. Together, our data indicate that the engraving was made by Homo erectus, and that it is considerably older than the oldest geometric engravings described so far. Although it is at present not possible to assess the function or meaning of the engraved shell, this discovery suggests that engraving abstract patterns was in the realm of Asian Homo erectus cognition and neuromotor control.”

Note also this research has resulted in a recalibration of the age of the Trinil site, where DuBois found the first fossils attributed to H. erectus.

Read the full article in Nature.

Noted paleoanthropologist Jean-Jacqes Hublin remarks "JThe age of the Trinil Homo erectus revised at 500-400 ka and another zig-zag by archaic humans" in a Tweet.

Another well known paleoanthropologist, Curtis Marean, teaching at Arizona State University and directing field research at Pinnacle Point on the South African coast, cautions healthu skepticism is needed.  There is no context for these mussel shells, Dr Marean says. They were rediscovered in a drawer. No note was taken at the time of their initial discovery, more than a century ago, of the sediments in whicj they were found, proximity to other artifacts or human remains, etc.

Marean is the author of several papers appearing in this NEWS column. See

"Early human use of marine resources and pigment in South Africa" from 2007.