Multimodal signalling in wild and captive orangutans: redundancy versus complementarity

动物与同种和异种的沟通使用多成分信号在每一个感官模态，采用视觉，听觉，嗅觉和其他信号。尽管越来越多的证据表明，非人类灵长类动物的交流，我们的语言进化的主要模型，本质上是多模态的，大多数研究都集中在孤立的手势或发声。然而，为什么我们最亲近的亲戚应该以单一或多种方式发出信号仍然知之甚少。到目前为止，我们对多模态信号的功能知之甚少，社会生态环境对交际行为的进化影响也知之甚少。此外，多模态信号产生和感知的个体发育对于理解交际行为的近端和最终机制至关重要。然而，发展研究仅限于多模态信号感知，而信号产生一直被忽视。鉴于越来越多的证据表明，社会经验对沟通发展的强烈影响，了解学习的多模态信号production.The拟议的项目是为了填补这些空白，通过研究如何以及为什么大猩猩使用信号成分的不同模式在种内通信的作用是至关重要的。在这项研究中，我将第一次系统地测试大猩猩的主要竞争假设（“备份信号”与“多重信息”）。我将采用多模态发展的方法来调查功能和个体发育的多模态通信在野生和圈养红毛猩猩（猩猩abelii/pygmaeus）。 由于红毛猩猩在社会性和树栖性方面的种内差异，我可以研究社会机会和生态环境在多大程度上影响了交际行为。具体来说，我将调查和比较的生产和响应单峰和多峰信号在圈养和野生两种猩猩，允许高度不同的社会和生态环境之间的比较（2x2比较）。此外，我将比较所获得的结果，从潘物种，黑猩猩和倭黑猩猩的相应数据。通过这三个方面的比较（Borneo-Sumatra，Freiland-Zoo，Pongo-Pan），我可以检验类人猿的交流行为与其社会生态生活方式的联系程度。反过来，这可能会为人类语言的进化提供新的见解，作为多模态系统的一部分，以及手势，面部表情和眼睛凝视等语音伴随信号的功能。

Animals communicate with con- and hetero-specifics using multicomponent signals in every sensory modality, employing visual, audible, olfactory and other signals. Despite growing evidence that the communication of nonhuman primates, our main model for the evolution of language, is intrinsically multimodal, most studies have focused on gesture or vocalization in isolation. However, why our closest living relatives should signal in single or multiple modalities is still poorly understood. So far we know very little about the function of multimodal signalling, and the evolutionary implications of the socio-ecological environment acting on communicative behaviour are poorly understood. Moreover, the ontogeny of multimodal signal production and perception is essential for an understanding of the proximate and ultimate mechanisms underlying communicative acts. Developmental research is however limited to multimodal signal perception, while signal production has been neglected. Given the growing evidence for a strong impact of social experience on communicative development, it is vital to understand the role of learning for multimodal signal production.The proposed project is designed to fill these gaps by examining how and why great apes use signal components of different modalities in intra-specific communication. In this study, I will for the first time systematically test the major competing hypotheses (‘backup signals’ versus ‘multiple messages’) in great apes. I will apply a multimodal-developmental approach to investigate function and ontogeny of multimodal communication in wild and captive orangutans (Pongo abelii/pygmaeus). Due to the orangutans’ intraspecific differences in sociability and their arboreality, I can examine to which extent social opportunities and ecological environment influence communicative behaviour. Specifically, I will investigate and compare the production of and responses to unimodal and multimodal signals in both species of orangutans in captivity and in the wild, allowing for the comparison between highly different social and ecological settings (2x2 comparison). In addition, I will compare the obtained results to corresponding data from the Pan species, chimpanzees and bonobos. With this threefold comparison (Borneo-Sumatra, Freiland–Zoo, Pongo-Pan), I can examine the extent to which the communicative behavior of great apes is linked to their socio-ecological lifestyle. In turn, this might provide novel insights on the evolution of human language as part of a multimodal system and the function of speech-accompanying signals like gestures, facial expressions and eye gaze.