Oceania encompasses thousands of islands, which are usually divided into four cultural areas: Micronesia, Polynesia, Australia, and Melanesia. Polynesia was the last area of the world to be settled; as such, those who inhabited the area brought complex societal constructs with them. For this reason, Polynesian art tends to be more cohesive and autocratic than other Oceanic art. Even so, the vast distances separating islands yield very different styles, from the exuberance of Hawaiian sculpture to the restraint of Cook Island figures. Polynesians excelled at woodcarving, depicting fierce gods with tremendous energy and power, and they created elaborate tattoos and decorative bark cloth. In the arts of New Zealand, the two main Polynesian artistic tendencies, one toward bold figural sculptures and the other toward the repetition of abstract forms, come together, as in the intricate, fluid decorations on Maori meeting houses. In Melanesia, a series of multiple migrations is echoed in the profusion of overlapping artistic styles; the emphasis is on bold colors and dramatic shapes. Large ancestral poles were erected as power images to assist in battle and for fertility. In Australia, a primary function of Aboriginal art is to facilitate contact with a mythological past era, called "Dreamtime". Bark paintings depict underworld creatures and symbolic motifs, and are used ceremonially to recreate cosmogonic myths. In New Zealand¹s Maori culture, woodcarving continues to be a vibrant practice with an important role in ensuring cultural continuity.