Abstract
We suggest that the emergence of consciousness in living organisms entailed new goals and new functions, which gave rise to a new category of selection, which we call mental selection. Mental selection involves ontogenetic choices that are directed towards consciously perceived and affectively evaluated patterns. It expands the types, targets and regimes of natural and sexual-social selection and is a scaffold on which human artificial selection emerged. We suggest that the functional effects of consciousness and the mental selection which it affords, were driven and enabled by the evolution of an open-ended form of associative learning (unlimited associative learning (UAL)). UAL enables animals to discriminate between composite percepts and acts and permits plastic self-learning and goal-directed behaviour driven by flexibly prioritized physiological needs, which enable flexible adjustments to a huge range of conditions and events during the animal's lifetime. We propose that UAL-based signal selection, involving for example, predator-prey, sexual and other social interactions, led to the evolution of intricate perceptual, emotional and motor patterns that could not have existed before consciousness evolved. These patterns, which can be thought of as signatures of consciousness, first appeared in the Cambrian era and scaffolded the evolution of imaginative animals and reflective humans.This article is part of the theme issue 'Evolutionary functions of consciousness'.