Data from: Parental effects alter the adaptive value of an adult behavioural trait

The parents' phenotype, or the environment they create for their young, can have long-lasting effects on their offspring, with profound evolutionary consequences. Yet virtually no work has considered how such parental effects might change the adaptive value of behavioural traits expressed by offspring upon reaching adulthood. To address this problem, we combined experiments on burying beetles (Nicrophorus vespilloides) with theoretical modelling, and focussed on one adult behavioural trait in particular: the supply of parental care. We manipulated the early life environment and measured the fitness payoffs associated with the supply of parental care when larvae reached maturity. We found that (1) adults that received low levels of care as larvae were less successful at raising larger broods, and suffered greater mortality as a result: they were low quality parents. Furthermore (2) high quality males that raised offspring with low quality females subsequently suffered greater mortality than brothers of equivalent quality, which reared larvae with higher quality females. Our analyses identify three general ways in which parental effects can change the adaptive value of an adult behavioural trait: by influencing the associated fitness benefits and costs; by consequently changing the evolutionary outcome of social interactions; and by modifying the evolutionarily stable expression of behavioural traits that are themselves parental effects.

亲本的表型（phenotype），即其为后代营造的生长环境，可对子代产生持久影响，并带来深远的进化后果。然而目前几乎尚无研究探讨这类亲本效应（parental effects）如何改变子代成年后所表达的行为性状的适应值。为解决这一问题，我们结合了埋葬甲（Nicrophorus vespilloides）的实验与理论建模，尤其聚焦于一项成年行为性状：亲本抚育供给。我们对幼虫的早期生活环境进行了操控，并在幼虫发育至成虫后，测量了与亲本抚育供给相关的适合度收益。研究结果显示：(1) 幼虫时期获得抚育水平较低的成虫，在抚育更大幼虫群时成功率更低，且因此面临更高的死亡率，这类个体属于低质量亲本。此外，(2) 与低质量雌性交配并抚育后代的高质量雄虫，其死亡率高于同质量但与高质量雌性交配抚育后代的雄性同胞。本研究通过分析，明确了亲本效应可通过三种通用途径改变成年行为性状的适应值：一是影响与之相关的适合度收益与成本；二是由此改变社会互动的进化结局；三是调控本身属于亲本效应的行为性状的进化稳定表达。