The study shows Lapita people introduced pottery to Papua New Guinea that had distinct markings, as well as new tool technologies and animals such as pigs. "We found lots of Lapita pottery, a range of stone tools and evidence for shaping of obsidian [volcanic glass] into sharp blades," Dr Shaw said. "As we dug deeper, we reached an even earlier cultural layer before the introduction of pottery. What amazed us was the amount of mammal bone we recovered, some of which could be positively identified as pig and dog. These animals were introduced to New Guinea by Lapita and were a