Archaeologists unearthed pieces of several wooden digging sticks from a plain at the foot of a low hill in Tuscany (Italy) where 171,000 years ago the shore of a lake was surrounded by grasslands and marshes - home to large grazing mammals, including the straight-tusked elephants whose bones litter the site.
     If you're a hunter-gatherer, the digging stick is your foraging multi-tool: about a meter long, one end rounded to offer a handle and the other tapered almost to a point; useful for digging up roots and tubers, hunting burrowing animals, or pounding and grinding herbs. Neanderthals of Middle Pleistocene Italy created and used digging sticks that would be familiar to modern hunter-foragers, like the Bindibu of Australia, Hadza of Tanzania, and San of southern Africa. In most modern hunter-gatherer cultures, digging sticks are women's tools.
     The finds date to a period when Neanderthals roamed the hills of southern Italy. Archaeologists excavating the site in 2012 found 39 broken pieces of the sticks, along with an assortment of stone tools. Of the 39 fragments, only about four pointed tips and six rounded handles survived, along with 31 pieces of shafts. Four of the handles and all of the tips had been broken during the tools' lifetimes.
     Researchers noticed that one of the digging sticks had a 1-millimetre-thick layer of black film on its shaft, its surface fractured in a square-like pattern reminiscent of charring. Chemical testing revealed that the wood had in fact been charred, as had 11 of the other pieces. All were charred evenly, on the same part of the stick, implying carefully controlled exposure to fire.
     Archaeologists say that the Neanderthals probably used fire to char the surface of the wood to make it easier to scrape off the bark and shape the ends. Boxwood is one of the strongest European hardwoods - perfect for a digging stick - but it's also difficult to shape with stone tools. Fire would have softened an outer layer and made it easier to work. When researchers tried working some boxwood branches, they found that they couldn't shape the handles and points without first charring the wood.
     Some archaeologists think that Homo heidelbergensis, an ancestor of Neanderthals, may have used a similar method to shape spears in a 300,000-year-old site in Germany, which come to much sharper points than the digging sticks from Italy, but lack evidence for the use of fire in their manufacture. That makes the digging sticks from Italy the earliest clear examples of wooden tools shaped with fire.

Edited from Popular Archaeology, Ars Technica (5 February 2018), Newsweek (6 February 2018)