The present results are situated within an emerging body of substantive and methodological critiques of the GFP (see e.g., Ashton et al., 2009; Ferguson et al., 2011). For instance, Rushton and Irwing’s (2011) analogy between the GFP for personality and ‘g’ in cognitive abilities appears to break down in several respects. Foremost, unlike ‘g’, for which higher scores are unambiguously better, the relation between personality traits and adaptation may be non-linear or moderated to a greater extent by environmental factors. For example, some personality theorists assert that extreme scores on otherwise beneficial personality traits are maladaptive, such as when high agreeableness connotes pathologically dependent behavior (Lowe, Edmundson, & Widiger, 2009). To the extent that extreme traits are generally maladaptive, the suggestion that the GFP evolved via directional selection (such that over time population means shifted in a certain direction because individuals at one end of a trait are more likely to survive) may be called into question (Ferguson et al., 2011).
