Oldest hominid engravings found by Leiden Univ. team

Researchers have found that the Homo erectus on the Indonesian island Java had used shells of freshwater mussels as material for tools and as a base for engravings half a million years ago. The finding provides new insight on the evolution of human behavior.

"Until now it was believed that the making of this kind of engravings was reserved for modern man (Homo sapiens) in Africa, from about 100 thousand years ago", says José Joordens, affiliated with the Faculty Archaeology at the Leiden University. He is the lead author of the publication on these findings in Nature (December 3rd, 2014).

A team of 21 researchers examined hundreds of fossil shells that come from the Homo erectus site Trinil on the island Java. The shells belong to the Dubois Collection that has been part of the Naturalis Biodiversity Center in Leiden since the 19th century. The shells were originally excavated by the Limburg physician and researcher Eugene Dubois.

They discovered an engraved geometric pattern on one of the shells. The research concluded that the pattern was not made by animals or by natural weathering processes and showed that the "zigzag pattern" was the work of Homo erectus.

By using two dating methods, researchers from the VU University Amsterdam and Wageningen University found that the engraved shell is between 430 thousand and 540 thousand years old. That makes the engraving at least four times older than the hitherto known oldest engravings, which were found in Africa.

The research also shows that these early hominids opened freshwater mussels very cleverly. They used a sharp shark tooth to bore a hole at exactly the point where the muscle that holds the shell closed is attached. "The accuracy with which these early hominids worked indicates a detailed knowledge of the anatomy of the shellfish and a good manual dexterity", says researcher and fossil shells expert Frank Wesselingh.

This finding throws unexpected light on the skills and behavior of Homo erectus. It also shows that Asia is a promising and relatively unexplored are when it comes to intriguing artifacts.