On the evolution of the human self: A data-driven review and reconsideration

We revisit the thesis we first offered in 1997, namely, that the human capacity called "the self" is the product of evolutionary pressures. A review of the literature accumulated in the 20 years prompted three changes to the original thesis. First, we expanded our 1997 conception of the self. We argue that the self consists of a multiplicity of cognitions, each of which may reflect the action of a different neural system. Second, we revised the timeline for the evolution of the human self. At least some components of the human self were present in hominids earlier than the 100,000 years-old date that we speculated served as the oldest-age boundary for the emergence of the self. Third, we supplemented the evidentiary basis by relying on advances in brain structure, brain function, and the genetic underpinnings of the brain. In comparison to the state of knowledge in 1997, there is more reason to assert in 2017 that humans have the capacity to experience a self because this trait was selected via evolution.