This CBC article covers he interesting research on Polynesian cultures:
Why did so many ancient societies around the world make human sacrifices to appease the gods? A new study supports the theory that the practice may have played a key role in keeping the poor downtrodden and the elites in power.
And barbaric as it sounds, human sacrifice may have created one path for more advanced civilizations, according to the study.
"Unpalatable as it might be, our results suggest that ritual killing helped humans transition from the small egalitarian groups of our ancestors, to the large stratified societies we live in today," concludes the study published this week in Nature.
Anthropologists and archeologists had previously suggested that ritual human sacrifice might help build and sustain social class systems. Researchers at the University of Auckland, the Max Planck Institute for the Science of Human History and Victoria University, wanted to see if they could find evidence of that.
They looked at 93 Austronesian cultures, which share similar languages and were spread across the South Pacific from Madagascar to Easter Island to the Pacific Islands and New Zealand. About 40 of them practised some kind of ritual killing, including burning, drowning, strangulation, bludgeoning, burial, being cut to pieces, being crushed beneath a newly built canoe or being rolled off the roof of a house and decapitated.