Conservation ethics (i.e. moral concern for non-human organisms) are widespread, but we lack a comprehensive explanation for why people care about other species at all, and why they express strong moral concern for some species but not others. Recent theory suggests that conservation ethics might be rooted in cooperation between humans and members of other species. Building on central predictions of this eco-evolutionary theory, we conducted an online study (N = 651) and exploratory factor analysis to develop two scales that independently measure perceived fitness interdependence (PFI) and conservation ethics. The PFI scale measures perceived shared fate as a proximate indicator of human fitness interdependence with non-human organisms (i.e. the degree to which humans and other organisms influence each other's evolutionary success, that is, survival and reproduction). We designed the conservation ethics scale to measure moral beliefs and attitudes regarding those organisms. Both scales are composed of two factors and demonstrate good internal reliability. By combining insights from various branches of the evolutionary human sciences, including evolutionary anthropology, evolutionary psychology and human behavioural ecology, we offer empirical tools to investigate eco-evolutionary foundations of conservation ethics and behaviour.

To answer tantalizing questions such as whether animals are moral or how morality evolved, I propose starting with a somewhat less fraught question: do animals have normative cognition? Recent psychological research suggests that normative thinking, or ought-thought, begins early in human development. Recent philosophical research suggests that folk psychology is grounded in normative thought. Recent primatology research finds evidence of sophisticated cultural and social learning capacities in great apes. Drawing on these three literatures, I argue that the human variety of social cognition and moral cognition encompass the same cognitive capacities and that the nonhuman great apes may also be normative beings. To make this argument, I develop an account of animal social norms that shares key properties with Cristina Bicchieri's account of social norms but which lowers the cognitive requirements for having a social norm. I propose a set of four early developing prerequisites implicated in social cognition that make up what I call naïve normativity: (1) the ability to identify agents, (2) sensitivity to in-group/out-group differences, (3) the capacity for social learning of group traditions, and (4) responsiveness to appropriateness. I review the ape cognition literature and present preliminary empirical evidence supporting the existence of social norms and naïve normativity in great apes. While there is more empirical work to be done, I hope to have offered a framework for studying normativity in other species, and I conclude that we should be open to the possibility that normative cognition is yet another ancient cognitive endowment that is not human-unique.

Morally progressive social changes seem to have taken place with the onset of democratic governance, the abolition of slavery, the rise of gender equality, and other developments. This essay attempts to demonstrate that natural and objective moral facts are a plausible cause of some morally progressive social changes. Since this hypothesis is a version of naturalistic moral realism, I call it the Naturalist-Realist Hypothesis (NRH). To support the NRH, I argue that objective moral facts are natural facts pertaining to the impartial promotion of well-being within a population of agents facing a social dilemma. I then describe a mechanism to explain how natural and objective moral facts so construed may cause some morally progressive social changes. I suggest that the NRH is a credible hypothesis because it is compatible with empirical findings from research on the evolution of moral cognition and on the sociology of mass political movements.