A multinational group of scientists led by Prof Wil Roebroeks of Leiden University in the Netherlands has discovered the earliest known engraving on a fossilized shell from the famous Homo erectus site of Trinil, on the Indonesian island of Java. Pseudodon shell with the engraving made by Homo erectus. Image credit: Wim Lustenhouwer / VU University Amsterdam. While cataloging hundreds of freshwater mussel shells collected at the end of the 19th century...