One thing that’s definitely gotten better over time: not as much ritualistic human sacrifice.

But a new study published Monday in Nature revisits the ancient practice to look for fresh insights. The scientists found that, for better or worse (and only worse for the victims, of course), human sacrifice helped create the hierarchies present in many modern societies.

The scientists from the University of Auckland and Victoria University of Wellington, both in New Zealand, found that ritual sacrifice may have spurred the transition of small, egalitarian societies to large, stratified ones. The study examined 93 traditional Austronesian cultures (speakers of a family of languages in parts of Africa, Asia and Oceania).

They looked at whether and how these cultures used ritual sacrifice — 40 of them practiced it — and how it affected social organization. The cultures were then divided into groups: egalitarian, moderately stratified and highly stratified. They were defined by the presence or absence of social hierarchy, and the rate of social mobility.