This is quite an important paper: no other species than humans shows #Inequityaversion, the basic element of fairness. This is fundamental to #huntergatherer ways of life.

'Disadvantageous inequity aversion (IA), a negative response to receiving less than others, is a key building block of the human sense of fairness. While some theorize that IA is shared by species across the animal kingdom, others argue that it is an exclusively human evolutionary adaptation to the selective pressures of cooperation among non-kin. Essential to this debate is the empirical question of whether non-human animals are averse towards unequal resource distributions.'

https://royalsocietypublishing.org/doi/10.1098/rspb.2024.1452