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

合作在自然界无处不在。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产生的？探究这个问题涉及到研究个体行为如何促进合作，如奖励、惩罚、选择或转换合作伙伴。这些行为发生在社会网络的大背景下-合作伙伴的“市场”定义了特定类型的合作伙伴的供应和需求。为了检验关于合作的假设，研究一个有机体是有用的，它形成了长期的社会关系，并做出了关于帮助哪些伙伴的复杂决定。这项工作将使用普通吸血蝙蝠作为模式生物，因为它们通过梳理和与相关和不相关的长期伙伴分享反刍食物来合作。对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”如何发展成为以牺牲自己为代价互相帮助的食物分享伙伴。了解吸血蝙蝠是如何形成社交网络的，可以为了解个体行为如何塑造关系、社会结构、合作以及信息或疾病的传播提供一般性的见解，因为吸血蝙蝠经常以牛的血为食。通过在蝙蝠和牛身上安装微小的无线传感器，研究小组还将以每分钟的细节跟踪“蝙蝠网络”和“蝙蝠-牛网络”的动态。这些大型数据集对于基于网络的过程建模非常有用，例如病毒如何在人群中传播或跨物种传播（例如蝙蝠到牲畜）。行为生态学家不同意的因素，如健身相互依存，合作伙伴的选择，和合作伙伴的控制稳定的社会关系的相对重要性。这项研究旨在通过实验性地操纵新的合作关系的形成来解决这些长期存在的争论。这项工作解决了四个层次的日益复杂性：个人，关系，网络和动态多层网络。第一，合作性在个体之间是如何变化的？为什么会变化？该小组将研究神经内分泌的原因和结果的个体差异，在allogoroming和食物共享吸血蝙蝠。第二，陌生人如何形成新的合作关系？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：吸血蝙蝠的互惠性。第三，不同的社会互动网络如何相互影响？这项工作将把栖息地内的合作与社会觅食联系起来，并将产生丰富的数据集，使人们能够研究社会结构、社会学习和病原体传播。最后，随着时间的推移，合作伙伴的可用性和质量的变化如何影响不同合作执行战略的成功？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，并通过在投资高成本食物共享之前有条件地升级低成本的梳理投资（“提高赌注”）来形成新的合作关系。该奖项反映了NSF的法定使命，并被认为值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估来支持。

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.