Studies on animal temperaments (consistent differences in behaviors across contexts) and behavioral syndromes (suites of correlated behaviors across contexts) have surged in recent decades. Accordingly, behavioral ecologists have gained greater appreciation for their evolutionary role and significance. Yet, despite their importance as potential evolutionary drivers, research focused on temperament and syndromes in shaping hybridization events is vastly understudied. Case studies have shown that hybridization has multiple effects on these phenomena, such as eliminating syndromes present in parental lineages and generating novel syndromes within hybrids. Here, we assessed temperament and syndromes in a naturally occurring rattlesnake hybrid zone (Crotalus scutulatus × viridis). We used laboratory behavioral assays to quantify defensive and explorative behaviors, and tested whether these traits were correlated with spatial and hunting behaviors of free-ranging individuals. C. viridis was more significantly more prone to rattle than C. scutulatus during handling tests. Similarly, hybrid individuals that had a greater proportion of their genome derived from C. viridis were also more prone to rattle. Parental and hybrid snakes exhibited varying syndromes in defensiveness and exploratory behaviors, yet further research is necessary to determine whether they impact hybrid fitness by creating mismatches between temperaments and predation pressures under natural conditions.

© 2025. The Author(s).

近年来，关于动物性格（不同情境下行为的一贯差异）和行为综合征（不同情境下的相关行为组合）的研究显著增加。因此，行为生态学家对它们的进化作用和意义有了更深刻的认识。然而，尽管它们作为潜在进化驱动力的重要性显而易见，但专注于性格和综合征在塑造杂交事件中的研究却远远不足。案例研究表明，杂交化对这些现象有多重影响，例如消除亲缘谱系中存在的行为综合征，并在杂种中产生新的综合征。在这里，我们评估了一条自然发生的响尾蛇杂交带（Crotalus scutulatus × viridis）的性格和综合征。我们使用实验室行为测试量化防御性和探索性行为，并检验这些特征是否与自由活动个体的空间行为和狩猎行为相关联。在处理测试中，C. viridis 显著比 C. scutulatus 更倾向于发出响声。类似地，具有更多源自 C. viridis 基因组的杂种个体也更倾向于发出响声。亲缘蛇类和杂种蛇类展示了防御性和探索性行为的不同综合征，但需要进一步的研究来确定它们在自然条件下是否通过性格与捕食压力之间的不匹配影响杂交适应度。

© 2025. The Author(s).