Adaptive individual differences

Individuals differ in innumerable ways, some adaptive, some maladaptive, an d some neutral. Personality theories, we argue, can profit from distinguish ing among these importantly different types of individual variation. This a rticle outlines a taxonomy of origins of individual differences-environment al sources of adaptive differences (e.g., early environmental calibration), heritable sources of adaptive differences (e.g., adaptive self-assessment of heritable qualities), nonadaptive sources of individual differences (e.g ., incidental by-products of adaptive variation), and maladaptive sources o f individual differences (e.g., epigenetic trauma). The second section outl ines empirical procedures for confirming or falsifying the differing concep tions of individual differences, with a special focus on empirically distin guishing adaptive individual differences from those that are maladaptive or nonadaptive. The final section highlights the importance of individual dif ferences for solving social adaptive problems.