Indigenous Australian rock art is the oldest and richest unbroken tradition of art in the world, dating as far back as 60,000 years and spread across hundreds of thousands of sites. These rock paintings served several functions. Some were used in magic, others to increase animal populations for hunting, while some were simply for amusement. Sculpture in Oceania first appears on New Guinea as a series of stone figures found throughout the island, but mostly in mountainous highlands. Establishing a chronological timeframe for these pieces in most cases is difficult, but one has been dated to 1500 BC.