A quantitative genetics approach to cross-validate lab- versus field-based behavior in novel environments

Conclusions about the adaptive nature of repeatable variation in behavior (i.e., “personality”) are often based on laboratory-based behavioral assays. However, the expression of genetic variation differs between laboratory and field. Laboratory-based behavior might not predict field-based behavior thus, cross-context validation is required. We therefore estimated the correlation between an established laboratory and field assay of activity in a novel environment applied to wild great tits (Parus major), both of which have been used as proxies for ‘exploration tendency’. Both behaviors had similar repeatability (R = 0.35 vs. 0.37) but differed in heritability (h² = 0.06 vs. 0.23), implying differences in evolvability. Unexpectedly, they were independent, thus reflecting expressions of two distinct underlying characters. Post hoc simulations show that sampling bias did not explain the lack of correlation.  Laboratory-based assays may reflect fear and exploration, but field-based assays es...