in former times New Guinea’s available root crops were limiting for calories as well as for protein, because they do not grow well at the high elevations where many New Guineans live today.
If this was truly the case, then why did humans move to and continue to live in those areas despite the issues with low protein crops, a lack of game, and weather conditions that did not support either a hunter-gatherer or agricultural lifestyle?
Is there a difference in population density between the lowlands and the highlands?
