Evolution of Parent-Offspring Communication: Who Controls Resource Allocation and Is Signalling Costly?

亲子沟通在物种中很常见，父母在孵化或出生后反复为后代提供资源。亲子沟通最近吸引了大量的理论和经验的兴趣，因为它提供了关键的见解，父母和他们的依赖后代之间的潜在利益冲突的表型表现。当父母为子女提供资源时，父母与子女之间的冲突是可以预料的，因为父母提供照顾会产生成本，而且父母与子女之间的关系不对称。由于亲子冲突，后代应该要求父母提供比父母准备提供更多的资源。然而，如果后代这样做，父母应该被选择忽略后代乞讨的表现，在这种情况下，亲子沟通将是进化上不稳定的。因此，行为生态学的一个关键目标是了解父母和后代的沟通如何在父母和后代有分歧但重叠的进化利益的情况下保持进化稳定。最近的决议模型作出可测试的预测表型的父母和后代的冲突的基础上发挥的策略明确的假设结果。这些模型表明，亲子沟通可以在解决亲子冲突中发挥关键作用。目前有三个主要类别的这种决议模型：诚实的信号，争夺竞争和无成本的乞讨模型。诚实的信号模型表明，父母受益于监测昂贵的后代乞讨显示器，因为这种显示器提供诚实和可靠的信息，后代的营养需求，这反过来又允许父母控制资源的分配。相反，争夺竞争模型表明，代价高昂的后代乞讨是兄弟姐妹之间争夺竞争的一种形式，资源分配是在后代而不是父母的控制下。最后，无成本模型表明，后代乞讨和亲子沟通可以是进化稳定的，即使乞讨不产生成本的后代。区分这三种类型的模型仍然是行为生态学中一个重要的未解决的问题。这些模型对后代信号和父母的反应做出了非常相似的预测，但基于不同的假设，即谁控制资源分配以及乞讨是否昂贵。本项目试图通过测试的关键假设，这些模型之间的区别在于使用埋葬甲虫Nicrophorus vespilloides作为研究系统。这个项目的第一个目的是建立资源分配是否是由父母控制，假设诚实的信号和无成本的乞讨模型，或控制的后代所假设的争夺竞争模型的乞讨。第二个目的是测试乞讨是否会产生成本的后代所假设的诚实的信号和争夺竞争模型的乞讨或乞讨是否是免费的免费模型所假设的乞讨。关于谁控制资源分配以及乞讨是否昂贵的信息将被用来区分现有的亲子沟通进化模型。这个项目将有助于我们理解的父母与子女的沟通和解决父母与子女的冲突，通过提供信息的关键假设谁控制资源分配和乞讨是否是昂贵的或没有从一个单一的研究系统。

Parent-offspring communication is common in species where parents provide their offspring repeatedly with resources after hatching or birth. Parent-offspring communication has recently attracted much theoretical and empirical interest because it provides key insights into the phenotypic manifestation of underlying conflicts of interest between parents and their dependent offspring. Parent-offspring conflict is expected when parents provide their offspring with resources because parents incur costs from providing care and because there are asymmetries in relatedness between parents and offspring. Due to parent-offspring conflict, offspring should demand more resources from their parents than parents are prepared to provide. However, if offspring do so, parents should be selected to ignore offspring begging displays, in which case parent-offspring communication would be evolutionarily unstable. Thus, a key aim in behavioural ecology is to understand how parent-offspring communication can be evolutionary stable in situations where parents and offspring have diverging but overlapping evolutionary interests. Recent resolution models make testable predictions about the phenotypic outcome of parent-offspring conflict based on explicit assumptions about the strategies played by parents and offspring. Such models suggest that parent-offspring communication can play a key role in resolving parent-offspring conflict. There are currently three main classes of such resolution models: honest signalling, scramble competition and cost-free models of begging. Honest signalling models suggest that parents benefit from monitoring costly offspring begging displays because such displays provide honest and reliable information on the offspring's nutritional needs, which in turn allow the parents to control the allocation of resources. By contrast, scramble competition models, suggest that costly offspring begging is a form of scramble competition among siblings, and that resource allocation is under offspring rather than parental control. Finally, cost-free models suggest that offspring begging and parent-offspring communication can be evolutionarily stable even if begging does not incur costs to the offspring. Distinguishing between these three types of models remains an important unresolved problem in behavioural ecology. The models make very similar predictions concerning offspring signalling and parental responsiveness, but are based on different assumptions concerning who controls resource allocation and whether begging is costly or not. This project seeks to distinguish between these models by testing the critical assumptions upon which the alternative models rests using the burying beetle Nicrophorus vespilloides as study system. The first aim of this project is to establish whether resource allocation is controlled by parents, as assumed by honest signalling and cost-free models of begging, or controlled by offspring as assumed by scramble competition models of begging. The second aim is to test whether begging incurs costs to the offspring as assumed by honest signalling and scramble competition models of begging or whether begging is cost-free as assumed by cost-free models of begging. The information on who controls resource allocation and whether begging is costly or not will then be used to distinguish between existing models for the evolution of parent-offspring communication. This project will contribute to our understanding of the evolution of parent-offspring communication and the resolution of parent-offspring conflict by providing information on the critical assumptions of who controls resource allocation and whether begging is costly or not from a single study system.