Abstract: Variation in state, which is any factor that alters the value of decision options, is likely one of the most common drivers of personality differences. However, the general relationship between individuals’ body state and various personality metrics/average behavioral type, repeatability of behavior, and behavioral syndrome structure is still poorly resolved. Here, we manipulate body condition in three spider species (Agelenopsis aperta, Latrodectus hesperus, and Anelosimus studiosus) using contrasting feeding schedules. We then assessed the effects of historic feeding regime on individuals’ body condition, boldness, and foraging aggressiveness. We further assessed the effects of feeding regimes on the repeatability of boldness and aggressiveness and the presence/absence of correlations between these two traits. We found that feeding treatment impacted individuals’ average boldness and aggressiveness in two species (A. aperta and A. studiosus). We also noted that among-individual variance in both boldness and aggressiveness was severely reduced when A. aperta and A. studiosus were subjected to prolonged food restriction, steeply reducing repeatability in these traits. Finally, we noted that correlations between boldness and foraging aggressiveness were detectable only in one case, revealing no compelling relationship between food restriction and the presence/absence of behavioral correlations. Taken together, our results suggest that food restriction has only weak, circumstantial effects on individuals’ average personality type and the correlations between behavioral traits. However, there appears to be a robust positive relationship between food availability and the signature of consistent individual differences in behavior. Significance statement: Under laboratory conditions, we found that lower feeding rates sharply decreased the repeatability of aggressiveness and boldness in two spider species. In doing so, we provide the second body of evidence suggesting that a highly prevalent and ecologically relevant state variable, higher body condition, can increase the repeatability of foraging-related behavioral traits. Additionally, under some feeding regimes, we found that hunger levels could alter the average individual aggressiveness and boldness but not correlations between these traits. This work highlights the importance of state variables such as hunger in eroding behavioral repeatability, the defining trait of personality.
- Behavioral syndromes
- Food stress