It is well known that agriculture developed independently in New Guinea 7000 years ago, but evidence of its influence on how people lived has eluded scientists, until now. An archaeological dig in Papua New Guinea has for the first time uncovered strong evidence that a Neolithic period existed on the island about 5000 years ago.
      Scientists believe the cache of artifacts that were unearthed, including stone axes, pestles, figurative carvings and other tools, are the missing clues needed to make the case for a Neolithic period in New Guinea's prehistory.
      A team of archaeologists and scientists reported the excavations at Waim, an area located in the northern highlands of modern Papua New Guinea. Dr. Ben Shaw of UNSW Science says until now, there was little evidence to demonstrate that New Guinea had enjoyed its own Neolithic period like other global agricultural centers had.
      At Waim, the team was astounded by the sheer bulk and variety of tools that turned up in the one place. They found very finely carved pestles used for the grinding of food, stone axes and adzes, as well as carved figurines. One of them, a large fragment of carved stone depicting the brow ridge of a human or animal face dated at 5050 years old is now the earliest evidence of a carved expression of body form in Oceania.
      After examining the pestles under the microscope, co-author Dr. Judith Field identified microfossils, demonstrating they had been used to process some of the wetland crops native to New Guinea. "It is probably one of the most direct links that you can draw to the influence of agriculture upon human behavior at this time," Dr. Field says.
      Dr. Shaw says a grooved volcanic stone was found with ochre on it, suggesting that 5000 years ago humans were already using it to paint, stain and decorate. "When we looked at the grooves on this stone under the microscope, it looked as though they were shaped by having organic fibers pulled through them. The ochre on the stone would have stained these fibers a red color, which even today is how they sometimes stain fibers in the production of their woven string bags, or bilums. This has never been found at a site before."
      Another surprise was the uncovering of a large block of stone that had been ground and polished, which Dr. Shaw reckons was laid against a hillside and subsequently buried after the village at Waim was abandoned about 4000 years ago. He says that at about half a metre long and 30cm wide, it was a very unusual piece and had the team stumped as to what its purpose was.
      "While we were sitting there scratching our heads, one of the elders from the village came up and told us that this is how the old people used to make the axes: they would take a big block of stone, work it into shape, and then simply saw it into the individual sizes of the axes that they wanted." The type of ax that was associated with this stone template was previously thought to have been used by people coming into the area more than 2000 years later, which Dr. Shaw says "really floored us and blew us away".

Edited from PhysORG (26 March 2020)