From partner choice to equity - and beyond?

Baumard et al. provide an intriguing model where morality emerges from the dynamics of partner choice in mutualistic interactions. I discuss evidence from human and nonhuman primates that supports the overall approach, but highlights a gap in explaining the human specificity of moral cognition. I suggest that an essential characteristic of human fairness is to override concerns about merit in favor of promoting the welfare in others who are needy.