In 1952 the Danish archaeologists Johannes Iversen, Jörgen Troels-Smith, and Svend Jörgensen conducted an experiment to better understand how stone axes functioned in Neolithic Europe.  The team replicated wood handles based on the Sigerslev axe—an ancient axe found in a Danish bog—and hafted them with archaeological flint axes borrowed from the National Museum in Copenhagen. …

European colonisers first entered the high-elevation savannahs along the mountainous spine of New Guinea in the 1930s. Although explorers in the 19th Century could see the highland mountains from the sea, the colonisers were shocked to find over one million people lived in the surrounding montane valleys. These people practiced a traditional form of garden-based…