Abstract:
Persistent individual variation in behaviour, or \'personality\', is a widespread phenomenon in animals, and understanding the evolution of animal personality is a key task of current biology. Natural selection has been proposed to promote the integration of personality with animal \'intrinsic states\', such as metabolic or endocrine traits, and this integration varies with ecological conditions. However, these external ecological modulatory effects have rarely been examined. Here, we investigate the effects of thermal acclimation on between-individual covariations between physiology and behaviour in Asiatic toads (Bufo gargarizans) along an altitudinal gradient. Our results reveal that the thermal modulatory effects on the covariations depend on the altitudinal population. Specifically, at low altitudes, between-individual covariations are highly plastic, with risk-taking behaviour covarying with baseline glucocorticoids (GCs) under warm acclimation, but risk-taking and exploration behaviour covarying with resting metabolic rate (RMR) under cold acclimation. In contrast, between-individual covariations are relatively fixed at high altitudes, with risk-taking behaviour consistently covarying with baseline GCs. Furthermore, at low altitudes, changes in covariations between RMR and personality are associated with adjustment of energy management models. Evidently, animal physiological states that determine or covary with personality can adapt according to the seasonal thermal environment and the thermal evolutionary background of populations. Our findings highlight the importance of a multi-system physiological approach to understand the evolution of animal personality.
摘要:
行为的持续个体差异,或“个性”,是动物中普遍存在的现象,理解动物人格的进化是当前生物学的关键任务。自然选择被提出来促进人格与动物“内在状态”的融合,如代谢或内分泌特征,这种整合随着生态条件的变化而变化。然而,这些外部生态调节效应很少被研究。这里,我们研究了热适应对亚洲蟾蜍(Bufogargarizans)沿海拔梯度的生理和行为之间个体间协同变化的影响。我们的结果表明,对协方差的热调节作用取决于海拔人口。具体来说,在低海拔地区,个体间的共变是高度可塑的,在温暖适应下,冒险行为与基线糖皮质激素(GC)共同变化,但在冷适应下,冒险和探索行为与静息代谢率(RMR)相关。相比之下,个体间的协变量在高海拔地区相对固定,冒险行为与基线GCs一致一致。此外,在低海拔地区,RMR和个性之间协变量的变化与能源管理模型的调整有关。显然,决定或与个性共生的动物生理状态可以根据季节热环境和种群的热进化背景来适应。我们的发现强调了多系统生理方法理解动物人格进化的重要性。