Did Human Reality Denial Breach the Evolutionary Psychological Barrier of Mortality Salience? A Theory that Can Explain Unusual Features of the Origin and Fate of Our Species
Authors: Varki Ajit 
Published: October 2019

AbstractSome aspects of human cognition and behavior appear unusual or exaggerated relative to those of other intelligent, warm-blooded, long-lived social species––including certain mammals (cetaceans, elephants, and great apes) and birds (corvids and passerines). One collection of such related features is our remarkable ability for ignoring or denying reality in the face of clear facts, a high capacity for self-deception and false beliefs, overarching optimism bias, and irrational risk-taking behavior (herein collectively called “reality denial”). Such traits should be maladaptive for reproductive success when they first appear as consistent features in individuals of any species. Meanwhile, available data suggest that self-awareness (knowledge of one’s own personhood) and basic theory of mind (ToM, also termed mind-reading, intentionality etc.) have evolved independently several times, particularly in the same kinds of species mentioned above. Despite a long-standing opportunity spanning tens of millions of years, only humans appear to have gone on to evolve an extended ToM (multilevel intentionality), a trait required for optimal expression of many other unusual cognitive attributes of our species, such as advanced linguistic communication and cumulative cooperative culture. The conventional view is that extended ToM emerged gradually in human ancestors, via stepwise positive selection of multiple traits that were each beneficial. A counterintuitive alternate possibility is that establishment of extended ToM has been repeatedly obstructed in all other species with the potential to achieve it, due to a “psychological evolutionary barrier,” that would arise in isolated individuals of a given species that develop the genetic ability for extended ToM. Such individuals would observe deaths of conspecifics whose minds they fully understood, become aware of mortality, and translate that knowledge into mortality salience (understanding of personal mortality). The resulting conscious realization and exaggeration of an already existing intrinsic fear of death risk would have then reduced the reproductive fitness of such isolated individuals (by favoring personal survival over reproduction). This “psychological evolutionary barrier” would have thus persisted until hominin ancestors broke through, via a rare and unlikely combination of cognitive changes, in which two intrinsically maladaptive traits (reality denial and extended ToM) evolved in the minds of the same individuals, allowing a “mind over reality transition” (MORT) over the proposed barrier. Once some individuals broke through in this manner, conventional natural selection could take over, with further evolution of beneficial aspects of the initial changes. This theory also provides a unifying evolutionary explanation for other unusual features of humans, including our recent emergence as the dominant species on the planet, and replacement of all other closely related evolutionary cousins, with limited interbreeding and no remaining hybrid species. While not directly falsifiable by experiment, the MORT theory fits with numerous facts about humans and human origins, and no known fact appears to strongly militate against it. It is also consistent with most other currently viable theories on related subjects, including terror management theory. Importantly, it has major implications for the human condition, as well as for many serious current issues, ranging all the way from lack of personal health responsibility to ignoring anthropogenic global climate disruption, which now threatens the very existence of our species.