Doctoral Dissertation Research: Diet, cognition, and nutrient cycling in wild orangutan habitats

灵长类的认知进化被认为在一定程度上是由于为了寻找食物而需要在复杂多变的环境中航行。然而，对于现存的灵长类动物来说，生态变异性和认知复杂性之间的关系并不完全清楚。这个博士论文项目将使用创新和跨学科的方法来研究婆罗洲猩猩在其环境中的旅行路径，以了解这些灵长类动物如何实现特定的营养目标，并利用先前的信息来导航他们的环境以达到这些目标。更好地了解我们在世的近亲对它们的资源知道什么，以及它们如何利用这些信息做出觅食决定，为深化我们对我们自己物种复杂认知的起源和进化的理解提供了一个独特的机会。这项研究还将支持STEM领域中代表性不足的学生的学术培训和指导，促进实地的国际合作和科学能力建设，并通过提供一种方法来预测猩猩将如何、为什么以及何时通过其栖息地的不同部分，为当地的保护倡议做出贡献。通过分析动物在其环境中的旅行路径，人们对灵长类动物的空间认知研究越来越感兴趣。研究人员倾向于通过经典觅食理论的镜头来检查旅行决策，但观察到的动物的空间行为很少反映觅食模型设定的期望。这可能是因为对觅食和旅行决定的解释通常集中在卡路里上，而实际上觅食者也可能有特定的营养目标，并使用先前的信息导航来达到这些目标。这个项目将通过对婆罗洲猩猩的研究来研究空间认知如何促进灵长类动物的营养平衡。猩猩是一个理想的模型系统，因为它们生活在高度可变的环境中，不生活在社会群体中，因此做出独立旅行和觅食的决定。之前大多数关于空间记忆和饮食的研究都缺乏认知的生态学相关性，或者难以量化认知在野外的觅食。在这个项目中，食物分配、可获得性和营养方面的数据将使用人工采样和现代遥感技术相结合的方式进行量化。关于测距和觅食的数据将通过焦点观测收集，其中饮食和GPS数据将每隔两分钟收集一次。将随机采集尿样，以监测营养和能量状况。这些数据将通过将运动生态学中的一组新的空间显式统计技术与营养生态学中的营养几何框架相结合来分析。

Primate cognitive evolution is thought to have been shaped, in part, by the need to navigate complex and variable environments in order to find food. However, the relationship between ecological variability and cognitive complexity is not fully understood for living primates. This doctoral dissertation project will use innovative and interdisciplinary methods to study the travel paths of Bornean orangutans through their environment, in order to understand how these primates fulfill specific nutritional targets and navigate their environment using prior information to reach those targets. A better understanding of what one of our closest living relatives knows about their resources, and how they utilize this information to make foraging decisions, provides a unique opportunity for deepening our understanding of the origins and evolution of complex cognition in our own species. This research will also support academic training and mentorship for students under-represented in STEM fields, foster international collaboration and scientific capacity building at the field location, and contribute to local conservation initiatives by providing a method to predict how, why and when orangutans will move through different parts of their habitat.There is increasing interest in the study of primate spatial cognition by analyzing travel paths of animals through their environment. Researchers tend to examine travel decisions through the lens of classical foraging theory, but the observed spatial behavior of animals rarely reflects the expectations set by foraging models. This may be because interpretations of foraging and travel decisions typically focus on calories, when in fact foragers may also have specific nutritional targets and navigate using prior information to reach those targets. This project will examine how spatial cognition facilitates nutritional balancing in primates by studying Bornean orangutans. Orangutans are an ideal model system because they live in highly variable environments, do not live in social groups, and thus make independent travel and foraging decisions. Most prior studies addressing spatial memory and diet have lacked the ecological correlates of cognition, or have struggled to quantify cognitive foraging in the wild. In this project, data on food distribution, availability, and nutrition will be quantified using a combination of manual sampling and modern remote sensing techniques. Data on ranging and foraging will be collected via focal observations in which dietary and GPS data will be collected at two minute intervals. Urine samples will be collected opportunistically to monitor nutritional and energetic status. These data will be analyzed by integrating a set of novel spatially explicit statistical techniques from movement ecology with the nutritional geometric framework from nutritional ecology.