Particularly along the north coast of New Guinea and in the islands north and east of New Guinea, the Austronesian people, who had migrated into the area somewhat more than 3,000 years ago, came into contact with these pre-existing populations of Papuan-speaking peoples. In the late 20th century, some scholars theorized a long period of interaction, which resulted in many complex changes in genetics, languages, and culture among the peoples. Kayser, et al. proposed that, from this area, a very small group of people (speaking an Austronesian language) departed to the east to become the forebears of the Polynesian people.