Boldness suppresses hoarding behavior in food hoarding season and reduces over-wintering survival in a social rodent

The "pace-of-life" syndrome (POLS) framework can encompass multiple personality axes that drive important functional behaviours (e.g., foraging behaviour) and that co-vary with multiple life history traits. Food hoarding is an adaptive behaviour important for an animal's adaptation to seasonal fluctuations in food availability. However, the empirical evidence for the relationships between animal personality and hoarding behaviour remains unclear, including its fitness consequences in the POLS framework. In this study, the Mongolian gerbil (Meriones unguiculatus), a social rodent, was used as a model system to investigate how boldness or shyness is associated with food hoarding strategies in the food hoarding season and overwinter survival or reproduction at individual and group levels. The results of this study showed that compared to shy gerbils, bold gerbils had a lower effort foraging strategy during the food hoarding season and exhibited lower overwinter survival, but bold–shy personality differences had no effect on overwinter reproduction. These findings suggest that the personality of the animal is a key factor that affects the foraging strategy during the food hoarding season in Mongolian gerbils. Personality may be related to energy states or the reaction to environmental change (e.g., predation risk, food availability) in bold or shy social animals. These results reflect animal life history trade-offs between "current versus future reproduction" and "reproduction versus self-maintenance", thereby helping Mongolian gerbils adapt to seasonal fluctuations in their living environment.

‘生活节奏综合征’（pace-of-life syndrome，POLS）框架可涵盖多个驱动关键功能行为（如觅食行为）、且与多种生活史性状协同变化的人格轴。食物贮藏是一项适应性行为，对动物适应食物可获得性的季节波动至关重要。然而，目前关于动物人格与贮食行为之间关系的实证证据仍不明确，其中也包括其在POLS框架下的适合度后果。本研究以社会性啮齿类动物蒙古沙鼠（Meriones unguiculatus）为模型系统，探究在食物贮藏季，个体与群体层面的大胆性与害羞性如何与食物贮藏策略、越冬存活及繁殖相关联。本研究结果显示，与害羞型沙鼠相比，大胆型沙鼠在食物贮藏季采取更低投入的觅食策略，且越冬存活率更低，但大胆-害羞人格差异对越冬繁殖无显著影响。上述发现表明，动物人格是影响蒙古沙鼠食物贮藏季觅食策略的关键因素。对于社会性的大胆或害羞型动物而言，人格可能与其能量状态或对环境变化（如捕食风险、食物可获得性）的反应相关。这些结果反映了动物在“当前繁殖与未来繁殖”以及“繁殖与自我维持”之间的生活史权衡，进而助力蒙古沙鼠适应其栖息环境的季节波动。