Data from: You eat what you are: personality-dependent filial cannibalism in a fish with paternal care

Many animal parents invest heavily to ensure offspring survival, yet some eventually consume some or all of their very own young. This so-called filial cannibalism is known from a wide range of taxa, but its adaptive benefit remains largely unclear. The extent to which parents cannibalize their broods varies substantially not only between species, but also between individuals, indicating that intrinsic behavioral differences, or animal personalities, might constitute a relevant proximate trigger for filial cannibalism. Using a marine fish with extensive paternal care, the common goby (Pomatoschistus microps), we investigated the influence of animal personality on filial cannibalism by assessing (1) behavioral consistency across a breeding and a nonbreeding context; (2) correlations between different breeding (egg fanning; filial cannibalism) and nonbreeding (activity) behaviors, and, in a separate experiment; (3) whether previously established personality scores affect filial cannibalism levels. We found consistent individual differences in activity across contexts. Partial filial cannibalism was independent of egg fanning but correlated strongly with activity, where active males cannibalized more eggs than less active males. This pattern was strong initially but vanished as the breeding season progressed. The incidence of whole clutch filial cannibalism increased with activity and clutch size. Our findings indicate that filial cannibalism cannot generally be adjusted independently of male personality and is thus phenotypically less plastic than typically assumed. The present work stresses the multidimensional interaction between animal personality, individual plasticity and the environment in shaping filial cannibalism.

诸多动物亲代都会投入大量资源以保障子代存活，但部分亲代最终会捕食部分乃至全部自身幼崽。这类被称为亲代食仔行为（filial cannibalism）的现象在众多类群中均有报道，但其适应性益处目前仍不甚明确。亲代捕食子代窝的程度不仅在物种间差异显著，在个体间亦存在极大不同，这提示内在行为差异——即动物性格（animal personalities）——或为亲代食仔行为的关键近因触发因素。本研究以具有高度父本抚育行为的海水鱼类——普通虎鱼（Pomatoschistus microps）——为研究对象，通过三方面评估探究动物性格对亲代食仔行为的影响：（1）繁殖与非繁殖情境下的行为一致性；（2）不同繁殖行为（护卵扇水、亲代食仔）与非繁殖行为（活动水平）间的相关性；此外在另一独立实验中，（3）预先测定的性格评分是否会影响亲代食仔行为的程度。研究发现，不同情境下的活动水平均存在稳定的个体差异。部分食仔行为与护卵扇水行为相互独立，但与活动水平显著相关：活动能力更强的雄性比活跃度较低的雄性会捕食更多鱼卵。该关联在繁殖初期表现显著，但随着繁殖季推进逐渐消失。整窝食仔行为的发生率随活动水平与窝卵数的增加而升高。本研究结果表明，亲代食仔行为通常无法脱离雄性个体性格进行独立调控，因此其表型可塑性较此前普遍认为的更低。本研究强调，动物性格、个体可塑性与环境三者间的多维交互作用，共同塑造了亲代食仔行为。