The coevolution of cognition and selection beyond reproductive utility

Humans feel that they appear and behave differently than other animals. We use cross-national survey data to assess sexual selection (mating choice) on cognition, and find it more than sufficient to explain the nearly three orders of magnitude faster rate of cognitive evolution as compared with Chimpanzees. We use archaeological evidence from six million years of hominin evolution to construct a cognitive metric and estimate evolutionary rates. The absolute values of estimates are not important, only reasonable estimates relative to Chimpanzees. The results suggest that once culture began storing and transmitting reasoning itself, cognition entered autocatalytic selection, creating abstractions the mind used for thinking, possibly outpacing biological change rates. We argue that leadership hierarchies evolved through selection, likely during the Y-chromosome bottleneck, not rational design. Once cognition accelerated, strategy space expanded continuously implying evolutionarily stable states were difficult to maintain, while predatory logic collapsed for states, species, and civilizations. However, when specialization concentrates in low-fertility roles and memetic pressure remains high, demographic population decline may occur. While similar selection regimes arose in other species, only hominins combined cognition with embodiment sufficient to sustain open-ended cultural–cognitive acceleration.