SYDNEY, March 26 (Xinhua) -- An archaeological dig in Papua New Guinea has for the first time found strong evidence that a Neolithic period - where agriculture brings about major cultural changes -- existed on the island about 5,000 years ago, according to a latest Australian-led research.

The cache of artefacts 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, the University of New South Wales said in a statement on Thursday.

University researcher Ben Shaw said that, until now, there was "little evidence to demonstrate that New Guinea had enjoyed its own Neolithic period" like other global agricultural centers had, despite well-documented evidence of agriculture on the Southern Hemisphere island in the past millennia.

"We already knew about the wetland crops like taro, yam, sugarcane and bananas from about 7,000 years ago in New Guinea," said Shaw, who was the lead author of the study published in academic journal Science Advances.

"But because the archaeology in this part of the world is not as well-known as places like China and the Middle East, we didn't really know how the development of agriculture changed human behaviors in the New Guinean landscape," he said.

Shaw pointed to changes that occurred as humans slowly shifted from a hunter-gatherer mode of existence to one that increasingly involved planting and harvesting crops.

"In Neolithic ages you see people transitioning to smaller living areas in the form of villages where they stayed for at least part of the year. And because they were staying in one place longer, people started changing their technology to look after crops. We also see more specialized skilled labor in the form of buildings and in the material objects they made and traded now that the society has a more stable sort of existence," he said.

The dig was also interesting for what the unearthed relics say about the antiquity of some of the technology still being used today in New Guinea, according to the researchers. A grooved volcanic stone was found with ochre on it, suggesting that 5,000 years ago humans were already using it to paint, stain and decorate, Shaw said.

Now that the researchers have demonstrated the missing link between agriculture and associated cultural changes in New Guinea, the next step is to "look more closely at the newly exposed treasures themselves".

"On the back of this we'll be doing a lot more research on individual artefacts to contextualize their use in New Guinea society at that time. So now that we've defined the edges of the puzzle in New Guinea, it's time to fill it in," he said.