Units of Human Adaptation
Humans are: a cooperative/competitive collection of genes, and a cooperative/competitive collection of individual organisms. Cooperation between cultures (lumpy collections of individuals) is the new evolutionary dynamic. For six million years, the interaction within cultures was more important than the interaction between cultures, in terms of adaptation and survival. We have passed through the threshold shifting greater weight toward the question of whether or not our separate cultural units can cooperate sufficiently to prevent nuclear or environmental self-extinction.
Our cultural units are both internally unstable, and externally confictual, as well, with the between-group conflicts driven by the European nation-state system.
Adaptive fitness is becoming ever more defined by survival of the most cooperative.