Geology
Topographical map of New Guinea.
Topographical map of New Guinea.

A central east-west mountain range dominates the geography of New Guinea, over 1600 km in total length. The western half of the island of New Guinea contains the highest mountains in Oceania, rising up to 4884 m high, and ensuring a steady supply of rain from the tropical atmosphere. The tree line is around 4000 m elevation and the tallest peaks contain permanent equatorial glaciers - which are disappearing due to a changing climate. Various other smaller mountain ranges occur both north and west of the central ranges. Except in high elevations, most areas possess a warm humid climate throughout the year, with some seasonal variation associated with the northeast monsoon season.

Puncak Jaya, sometimes known by its former Dutch name Carstensz Pyramid, is a mist covered limestone mountain peak 4884 m above sea level.

Another major habitat feature is the vast southern and northern lowlands. Stretching for hundreds of kilometers, these include lowland rainforests, extensive wetlands, savanna grasslands, and some of the largest expanses of mangrove forest in the world. The southern lowlands are the site of Lorentz National Park, also a UNESCO World Heritage Site.

The Sepik, Mamberamo, Fly, and Digul rivers are the island's major river systems that drain in roughly northeast, northwest, southeast, and southwest directions respectively. Many of these rivers have broad areas of meander and result in large areas of lakes and freshwater swamps.

In New Guinea is many of the world’s ecosystem types: permanent equatorial glaciers, alpine tundra, savanna, montane and lowland rainforest, mangroves, wetlands, lake and river ecosystems, seagrasses, and some of the richest coral reefs on the planet.

[edit] Cannibalism

New Guinea is well-known in the popular imagination for ritual cannibalism that was apparently practiced by some (but far from all) ethnic groups.[9] The Korowai and Kombai peoples of southeastern Papua are two of the last groups in the world said to have engaged in cannibalism in the recent past. In the Asmat area of southwestern Papua, it may have occurred up until the early 1970s. Among the Fore people in Papua New Guinea, ritualized cannibalism led to the spread of kuru, prompting the Australian administration to outlaw the practice in 1959.

Cannibalism may have arisen in New Guinea due to the scarcity of sources of protein. The traditional crops, taro and sweet potato, are low in protein compared to wheat and pulses, and the only edible animals available were small and unappetizing, such as mice, spiders, and frogs.[10] Anthropologists dispute this theory, pointing out that a number of medium-sized marsupials are endemic to the island, and are hunted by the natives, and that pigs were introduced several thousand years before contact with Europeans.