Papua New Guinea has several thousand separate communities, most with only a few hundred people. Divided by language, customs, and tradition, some of these communities have engaged in tribal warfare with their neighbors for centuries. The isolation created by the mountainous terrain is so great that some groups, until recently, were unaware of the existence of neighboring groups only a few kilometers away. About 160 languages seem to be totally unrelated either to each other or to the other major groupings. Native languages are spoken by a few hundred to a few thousand, although Enga, used in Enga Province, is spoken by some 130,000 people.
Most native languages are extremely complex grammatically.
The overall population density is low, although pockets of overpopulation exist. Rectangle divided diagonally from upper left corner to lower right corner. Archeological evidence indicates that humans arrived on New Guinea at least 50,000 years ago, probably by sea from Southeast Asia during an ice age period when the sea was lower and distances between islands shorter. Although the first arrivals were hunters and gatherers, early evidence shows that people managed the forest environment to provide food. Furthermore, evidence also shows proof of gardening at the same time that agriculture was developing in Mesopotamia and Egypt.