<p>Research about the evolution of morality suffers from the lack of a clear, agreed-upon concept of morality. In response to this, recent accounts have become increasingly pluralist and pragmatic. In this paper, I argue that 1) both the concept of morality and the broader understanding of what makes us moral include ethical and metaethical assumptions; 2) there is no uncontroversial descriptive notion available, and therefore settling on a particular concept inevitably entails such assumptions; and 3) what is lacking is a reflection on the role that ethical and metaethical assumptions play, suggesting that the debate would benefit from making them explicit. Claims about “the true origin of morality” can fruitfully be analyzed as “mixed claims”: claims that combine a causal-historical hypothesis (e.g., about the evolution of a certain ability, such as empathy or joint intentionality) with ethical or metaethical assumptions about which abilities or norms make us moral. Making such assumptions explicit advances the epistemic aims of transparency and comparability, and thereby helps to avoid rash conclusions regarding, for instance, the nature of moral progress. Finally, it helps to unpack the normative knowledge shared by behavioral scientists and comparative psychologists and to give this knowledge its proper place in research.</p>