Collaborative Research: Formation of new cooperative relationships in vampire bats - individual traits, partner choice, and network dynamics

合作无处不在。细胞一起工作形成身体，细菌与植物交换营养，合作的个体形成社会。自利单位之间的合作是如何出现的？回答这个问题需要研究个体行为是如何促进合作的，比如奖励、惩罚、选择或更换合作伙伴。这些行为发生在社交网络的更大背景下--定义特定类型合作伙伴的供应和需求的合作伙伴“市场”。为了检验关于合作的假设，研究一种形成长期社会关系并就帮助哪些合作伙伴做出复杂决定的有机体是有用的。这项工作将使用普通的吸血蝙蝠作为模式生物，因为它们通过梳理毛发，并与相关和无关的长期伴侣分享反胃食物来进行合作。吸血蝙蝠的实验室实验将模拟它们的自然社会环境，随着时间的推移操纵它们的合作互动，并测试“陌生人”如何发展成相互帮助、以牺牲自己为代价的食物分享伙伴。了解吸血蝙蝠是如何形成社交网络的，可以提供对个人行为如何塑造关系、社会结构、合作以及信息或疾病传播的一般见解，因为吸血蝙蝠通常以牛的血液为食。通过在蝙蝠和牛身上安装微小的无线传感器，研究团队还将逐分钟追踪“蝙蝠网络”和“蝙蝠-奶牛网络”的动态。这些大型数据集对于模拟基于网络的过程很有用，例如病毒将如何在种群中传播或跨物种传播(例如蝙蝠到牲畜)。对于健身相互依赖、伴侣选择和伴侣控制等因素对稳定合作社会关系的相对重要性，行为生态学家意见不一。这项研究旨在通过实验操纵随着时间的推移形成新的合作关系来解决这些长期存在的争论。这项工作解决了日益复杂的四个层次：个人、关系、网络和动态多层网络。首先，个体之间的合作能力如何以及为什么会有所不同？该团队将研究吸血蝙蝠在异基因修饰和食物分享方面的个体差异的神经内分泌原因和后果。第二，陌生人是如何形成新的合作关系的？这些实验将解决长达数十年的关于合作的教科书范例的争论：吸血蝙蝠之间的互惠。第三，不同的社交网络对彼此的影响有多大？这项工作将把巢内合作与社会觅食联系起来，并将产生丰富的数据集，从而能够研究社会结构、社会学习和病原体传播。最后，随着时间的推移，合作伙伴可用性和质量的差异如何影响不同合作执行策略的成功？这项工作将产生新的分析和计算模型，将新形式的社会复杂性纳入社会进化模型。最近的研究表明，吸血蝙蝠的合作性各不相同，在实验室和野外维持着相似的社交网络，并通过在投资于高成本食物分享之前有条件地升级低成本的美容投资来形成新的合作关系(“提高赌注”)。这个奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Cooperation is everywhere in nature. Cells work together to form bodies, bacteria exchange nutrients with plants, and cooperating individuals form societies. How does cooperation emerge among self-interested units? Answering this question involves studying how cooperation is promoted by individual behaviors such as rewarding, punishing, choosing, or switching partners. These behaviors occur within the larger context of the social network—the partner ‘market’ defining the supply and demand of particular kinds of partners. To test hypotheses about cooperation, it is useful to study an organism that forms long-term social relationships and that makes complex decisions about which partners to help. The work will use common vampire bats as a model organism because they cooperate by grooming and sharing regurgitated food with related and unrelated long-term partners. Lab experiments with vampire bats will simulate their natural social environments, manipulate their cooperative interactions over time, and test how ‘strangers’ develop into food-sharing partners that help each other at a cost to themselves. Understanding how vampire bats form social networks can provide general insights into how individual behaviors shape relationships, social structure, cooperation, and the spread of information or disease as vampire bats often feed on the blood of cattle. By attaching tiny wireless sensors on both bats and cattle, the research team will also track the dynamics of the “bat network” and the “bat-cow network” in minute-by-minute detail. These large datasets are useful for modelling network-based processes, such as how viruses would spread through a population or transmit across species (e.g. bats to livestock). Behavioral ecologists disagree about the relative importance of factors like fitness interdependence, partner choice, and partner control for stabilizing cooperative social relationships. The research aims to resolve these longstanding debates by experimentally manipulating the formation of new cooperative relationships over time. The work addresses four levels of increasing complexity: individuals, relationships, networks, and dynamic multi-layer networks. First, how and why does cooperativeness vary among individuals? The team will study of the neuroendocrine causes and consequences of individual variation in allogrooming and food sharing in vampire bats. Second, how do nonkin strangers form new cooperative relationships? The experiments will resolve a decades-long debate about a textbook example of cooperation: reciprocity in vampire bats. Third, how well do different social interaction networks influence each other? The work will link within-roost cooperation to social foraging and will generate rich datasets enabling studies of social structure, social learning, and pathogen transmission. Finally, how does variation in partner availability and quality influence the success of different cooperation enforcement strategies over time? The work will generate new analytical and computational models that will incorporate new forms of social complexity into models of social evolution. Recent work suggests that vampire bats vary in cooperativeness, maintain similar social networks in the lab and field, and form new cooperative relationships by conditionally escalating low-cost grooming investments before investing in higher-cost food sharing (“raising the stakes”).This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.