Balancing care and conflict: towards a better understanding of maternal aggression in canaries (Dataset)

Parental care improves offspring quality and survival and hence enhances parental fitness, still seemingly maladaptive parental behaviours such as directed aggression and neglect have been reported for a variety of species. While maternal aggression may represent a behavioural pathology, it could also be an adaptive strategy enabling optimal resource allocation in the context of a trade-off between current and future reproduction and other evolutionary conflicts of interest. This study evaluated the functional consequences of maternal aggression for developing offspring in the domestic canary (Serinus canaria). We found that maternal aggression significantly impaired offspring growth, but it did not reduce their survival, thus it might have lasting negative effects on offspring quality. Additionally, early-life exposure to aggression resulted in increased threatening behaviours in juvenile male but not female offspring, which again suggests that understanding the significance of an aggressive parenting style may require incorporating long-term effects. Females exhibiting maternal aggression did not lay larger second clutches, as would have been expected if aggression relates to a trade-off between current and future reproduction. Still, they laid overall larger clutches that were less variable in size. This indicates that there might be phenotypic differences, with females behaving aggressively towards their offspring being less flexible and too optimistic at egg laying. Thus, despite having negative effects on offspring growth parental aggression could nevertheless represent an adaptive, context-dependent behavioural strategy.

亲子照护能够提升后代的质量与存活率，从而增强父母的适应性。尽管如此，针对多种物种，仍有所报道的似乎不适应的亲子行为，如定向攻击和忽视。母性攻击可能代表着一种行为病理，但也可能是一种适应策略，在当前与未来繁殖以及其他进化利益冲突的权衡背景下，实现资源的优化分配。本研究评估了母性攻击对家鸽（Serinus canaria）后代发育的功能影响。我们发现母性攻击显著阻碍了后代的成长，但并未降低其存活率，因而可能对后代质量产生持久的负面影响。此外，早期接触攻击行为导致青少年雄性后代威胁性行为的增加，而雌性后代则没有，这再次表明，理解攻击型亲子风格的重要性可能需要考虑长期效应。表现出母性攻击的雌性并未产出更大的第二窝蛋，这与攻击行为与当前与未来繁殖的权衡相关的预期相反。然而，她们产出的蛋总体较大，且大小差异较小。这表明可能存在表型差异，对后代表现出攻击行为的雌性在产蛋时可能缺乏灵活性，过于乐观。因此，尽管对后代成长产生负面影响，亲子攻击行为仍可能代表一种适应性强、情境依赖性的行为策略。