The role of vibrational and airborne communication in the evolution of parental care in burying beetles

家庭生活被认为是从独居生活到社会生活和群居生活的“重大进化转变”的第一步。在家庭生活中，沟通是关键——动物必须认识伴侣，并能够评估他们的可信度和能力。他们还需要协调他们与伴侣和后代的实际互动。所有这些都是通过某种形式的交流来完成的，可能是声音的、振动的、化学的或视觉的。“社会复杂性假说”指出，在具有复杂社会系统的群体中，通信系统应该更加复杂。埋甲虫（Nicrophorus属）表现出相当复杂的家庭生活，伴侣和后代之间有许多互动。然而，尽管达尔文已经提到了小栉龙的鸣叫器官，但迄今为止绝大多数的研究都集中在通信的化学信号上，而化学和声学成分的组合等多模态信号根本没有被研究过。声音，可能还有振动，是甲虫在不同的情况下埋葬时产生的——在与竞争对手和捕食者的互动中，在埋葬时，在幼虫的喂养过程中，在雄性和雌性的相遇中，然而这些信号的具体功能到目前为止还不清楚。本项目的目的是研究甲虫掩埋过程中的空气和振动信号，以帮助我们了解复杂社会行为中的交流及其在亲代抚育进化中的作用。我们将研究在各种社会环境中使用的不同的空气和振动信号，以及许多种类的尼科弗鲁斯及其特定功能。此外，我们将研究是否需要两个通道进行通信。在项目的下一部分，我们将使用比较的方法来调查沟通在亲代抚育进化中的作用。这将有助于我们深入了解社会复杂性假说所提出的交流和社会性可能的共同进化。接下来，我们计划研究不同物种鸣叫器官的形态，以及这与产生的信号特征之间的关系。最后，我们将研究是否鸣声信号被用作多模态通信系统的一部分。因此，这项研究将首次深入了解在不同微孔虫物种的社会行为背景下，空气传播和基质传播的振动信号的使用，并将阐明这些信号是如何发出的。对交流、社会行为和亲代抚育的综合分析将为我们提供对社会复杂性假说的新见解，从而使我们对交流的进化有更深入的了解。

Family life is thought to be the first step in the ‘major evolutionary transition’ from solitary to social life and eusociality. In family life communication is key - animals have to recognize a partner and be able to evaluate their trustworthiness and capabilities. They also need to coordinate their actual interactions with their partner and their offspring. All of these are accomplished by some form of communication, be it acoustic, vibrational, chemical or visual. The ‘social complexity hypothesis’ states that communication systems should be more complex in groups with complex social systems. Burying beetles (genus Nicrophorus) exhibit a rather complex family life with numerous interactions between partners as well as their offspring. However, even though Darwin already mentioned the stridulatory organ in Nicrophorus, the vast majority of the studies to date have focused on chemical signals for communication, and multimodal signals such as combinations of chemical and acoustic components haven’t been studied at all.Sound, and probably vibrations, are produced by burying beetles in various different situations – in interactions with competitors and predators, while burying, during the feeding of the larvae and in encounters of male and female, yet the specific functions of these signals are unclear so far. The aim of this project is to investigate airborne and vibrational signals in burying beetles in order to contribute to our general understanding of communication during complex social behaviors and their role in the evolution of parental care. We will examine the different airborne and vibrational signals used in a variety of social contexts of numerous species of Nicrophorus and their specific function. Additionally, we will investigate whether both channels are needed to communicate. In the next part of the project we will use a comparative approach to investigate the role of communication in the evolution of parental care. This will serve to give us an insight into the possible co-evolution of communication and sociality as suggested by the social-complexity hypothesis. Next we plan to look at the morphology of the stridulatory organs of the different species and how this correlates with characteristics of the produced signals. Finally, we will investigate if the stridulatory signals are used as part of a multimodal communication system. This study will therefore provide first insights into the use of airborne and substrate-borne vibrational signals in the context of social behavior in different Nicrophorus species and will clarify how such signals are emitted. The combined analysis of communication, social behavior and parental care will provide us with new insights into the social complexity hypothesis and, through that, give us a deeper understanding on the evolution of communication.