Personality and metabolic scope in wild mice

It is intuitive to expect a relationship between animal personality (i.e. consistent individual behavioural differences) and metabolic rate, but the literature contains mixed results. Most studies have measured resting metabolic rate (RMR); yet, other metrics such as V̇O2,max and metabolic scope may also relate to personality. Here, we explored the relationships between personality (docility and exploration) and three metabolic traits (RMR, V̇O2,max and metabolic scope) in wild mice (Peromyscus leucopus). We found no among-individual correlation (rind) between personality and motivation to run during V̇O2,max trials, suggesting that using our standard forced-exercise test did not introduce a personality-related sampling bias. At the within-individual level, we found a positive and significant relationship between docility and metabolic scope, and the correlation was entirely driven by V̇O2,max. Finally, we found a positive and significant rind between RMR and time spent grooming during the open-field test, which may be caused by the stress response.