www.newscientist.com/article/dn22071-inequality-why-egalitarian-societies-died-out/ This article explains how hierarchy may have spread historically— it suggests as well that hierarchical “communes” would need to somehow spread to compensate for the draining of resources by the wealthy/powerful by expanding

www.newscientist.com/article/dn22071-inequality-why-egalitarian-societies-died-out/

forced to conquer others’ land in order to survive, not because they are somehow better. https://www.newscientist.com/article/dn22071-inequality-why-egalitarian-societies-died-out/

event because it took decades) and less a "destructive" event like e.g. the [Black Death](https://www.newscientist.com/article/mg17223184-000-did-bubonic-plague-really-cause-the-black-death).

www.academia.edu/10918787/Cross_View_Gait_Recognition_Using_Correlation_Strength https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.539385 https://www.newscientist.com/article/mg21528835-600-cameras-know-you-by-your-walk/ https://www.dailymail.co.uk/sciencetech/article-6357013/Chinese-gait-recognition-tech-IDs-people-walk.html https://www.businessinsider.com/china-says-new-surveillance-tech-can-id-people-from-their-walk-2018-11?op=1&r=US&IR=T

www.newscientist.com/article/dn16873-early-humans-may-have-cared-for-disabled-young Homo heidelbergensis