An evolutionary view of self-awareness

The capacity to be self-aware is regarded as a fundamental difference between humans and other species. However, growing evidence challenges this notion, indicating that many animals show complex signs and behaviors that are consonant with self-awareness. In this review, we suggest that many animals are indeed self-aware, but that the complexity of this process differs among species. We discuss this topic by addressing several different questions regarding self-awareness: what is self-awareness, how has self-awareness been studied experimentally, which species may be self-aware, what are its potential adaptive advantages. We conclude by proposing alternative models for the emergence of self-awareness in relation to species evolutionary paths, indicating future research questions to advance this field further.