According to evolutionary psychologists, at
Each mechanism within the brain has been shaped through natural, and sexual, selection, to solve the problems encountered within the environment of evolutionary adaptedness (EEA). Our ancestors evolved to survive over 4 million years of living as a nomadic hunter-gatherer, and only within the last 10,000 years have we developed a more sedentary, less nomadic lifestyle. Natural selection overcame many problems to ensure the survival of the species, adapting focussed, content-rich, highly specialised architecture that meet specific information-processing requirements: cooperation with our kin, dealing with our enemies, communication, including both language and non-verbal, identification and location of food, hunting, mate selection and avoiding infectious disease and poisonous food (Buss, 2009; 2009a; Cosmides & Tooby, 2013). Multiple adaptive mechanisms may also have evolved specifically for endurance.
Assuming an organism’s ability to increase the frequency of their genes in the next generation may be a result of one, or more, psychological adaptations to the EEA. Such adaptations, that offered an advantage, would, therefore ‘proliferate’ in subsequent generations, and may be different between EEA’s. As an example, EEA ‘A’ may have been a time when food was in plentiful supply, whilst EEA ‘B’ may have been during an extended period of drought, climatic extremes