Interspecific information transfer as a driver of community structure

是什么推动了动物物种在空间和时间上的丰度和分布？到目前为止，这个生态学和自然保护的核心问题主要是通过研究捕食者-猎物关系的影响和对有限资源（如食物）的竞争来解决的。然而，越来越清楚的是，动物也可以作为重要的信息来源对彼此产生重大影响，例如，当它们通报捕食者的存在或食物的位置时。物种间信息交换的潜在重要性从自然界中广泛存在的混合物种群（从蜘蛛、鱼类到鸟类和哺乳动物）中可见一斑。然而，目前几乎没有人知道住在有价值的线人旁边的优势如何影响物种之间的社会吸引模式。我们的研究从理论和实证相结合的角度来解决这个问题。我们将建立一个通用模型来预测信息利益如何塑造自然界中混合物种群体的组成。我们的模型将考虑到群体生活的主要成本和收益：(1)聚集许多眼睛、耳朵和鼻子所带来的信息收益；(2)当捕食者攻击时，与其他可能被捕食者而不是你靠近所带来的收益；(3)有限资源竞争加剧所带来的成本。为了在现实世界中测试我们的模型，我们在实地研究中关注了主导非洲大草原的混合物种食草动物群体。众所周知，当发出警报信号时，这些动物的许多眼睛、耳朵和鼻子会产生所有重要的信息益处。为了确定该系统中物种之间的社会吸引模式如何取决于它们作为信息提供者的价值，我们使用捕食者模拟和回放实验来确定(i)群落中每个物种的警报信号中包含的信息以及（ii）这些信息在物种之间传递的程度。我们还将获得每个草食物种对社区中各种捕食者的脆弱性的措施，以及饮食重叠时食物竞争的成本。在此基础上，我们将能够使用社会网络分析来测试交流的作用（相对于其他成本和收益）作为物种之间群体形成的驱动因素。因此，大草原食草动物的研究将允许我们通过以下方式解决生物学中的基本问题：(1)揭示群落中哪些物种在一起以及为什么在一起；(2)确定物种之间共存的本质：多物种群体是互利的，还是当一个物种寄生在另一个物种产生的信息上时形成的？该项目将通过将交流利益整合到经典的基于食物的生态系统结构模型中，为自然环境中物种之间的基本联系提供新的见解。通过建立新的基本原则，形成物种之间的社会联系，这项研究将带来对生态系统动态的更深入的理解，这对于确定保护优先事项至关重要。我们的概念框架将使保护主义者能够评估关键物种的减少何时可能通过影响其他物种的生存而对整个生态系统产生影响，以及这些间接影响何时可能成为濒危物种的保护问题。

What drives the abundance and distribution of animal species in space and time? This central question in ecology and conservation has so far been approached mainly by investigating the impact of predator-prey relationships and competition for limited resources such as food. However, it is becoming increasingly clear that animals may also have substantial effects on each other by acting as critical sources of information, for example when they communicate the presence of a predator or the location of food. The potential importance of information exchange between species is evident from the widespread occurrence of mixed-species groups in nature, in taxa ranging from spiders and fish to birds and mammals. Yet, currently almost nothing is known about how the advantage of living next to valuable informants affects patterns in social attraction between species. Our study addresses this question from an integrated theoretical and empirical angle. We will build a general model to predict how information benefits shape the composition of mixed-species groups in nature. Our model will take into account the key costs and benefits from group life: (i) the information benefits from joining many eyes, ears and noses, (ii) the benefit of being close to others that may be eaten instead of you when predators attack, and (iii) the costs from increased competition over limited resources. To test our model in the real world, we focus on the mixed-species groups of herbivores dominating the African savannas in a field study. The many eyes, ears and noses in these herds are known to result in all-important information benefits when alarm signals are emitted. To determine how patterns in social attraction between species in this system depends on their value as informants, we use predator simulations and playback experiments to determine (i) the information contained in the alarm signals from each species in the community and (ii) to what extent this information is transferred between species. We will also obtain measures of the vulnerability of each herbivore species to the various predators in the community as well as costs from food competition when diets overlap. On this basis, we will be able to use social network analysis to test the role of communication (relative to other costs and benefits) as a driver of group formation between species. The savannah herbivore study will thus allow us to address fundamental questions in biology by (i) revealing which species within the community group together and why, and (ii) establishing the nature of coexistence between species: are multispecies groups mutually beneficial or do they rather form when one species parasitizes on the information produced by another? The project will provide novel insights into the basic links between species in the natural environment by integrating communication benefits into classical food-web-based models of ecosystem structure. By establishing new fundamental principles that shape the social associations between species, the study will bring a deeper understanding of ecosystem dynamics that can be critical for identifying conservation priorities. Our conceptual framework will allow conservationists to assess when declines in key species are likely to have repercussions throughout the ecosystem by affecting the survival of others, and when these indirect effects are likely to become a conservation concern for endangered species.