Interplay between trait variation, food web dynamics and maintenance of biodiversity

个体、种群和群落内部的性状变异使它们能够适应不断变化的环境条件，从而产生包括生态进化动力学在内的生物量-性状反馈。利用数学模型，我们将有助于建立一个统一的理论，明确考虑这些反馈如何影响捕食者-猎物系统和更复杂的食物网的结构和动态。我们假设：(1)直立性状变异（功能多样性）影响生物量和性状动态；(2)这反过来影响性状变异的维持，并与性状之间的权衡相一致。我们将使用四种互补的模型方法：多物种或多克隆排序模型，全性状分布模型，通过明确描述潜在性状分布的均值和方差的动态近似全模型的集合模型，以及通过将多物种模型与集合方法相结合同时考虑种内和种间性状变化的杂交模型。这使我们能够调查交织在一起的生态和进化过程，并测试我们的结果对模型假设的稳健性。我们的主要目标是：1。综合目前双营养食物网模型中生物量-性状反馈的理论。我们关注(1)不同的食物网结构如何通过猎物和捕食者的进化多样化而进化；(2)结构、功能特征、权衡和特征变异来源的差异如何影响群落动态，例如解释不寻常的捕食者-猎物动态。这包括考虑一个多维特征空间。将我们的模型扩展到包括食物链和行内捕食在内的三营养系统，在更抽象但更容易处理的捕食者-猎物模型和更现实的复杂食物网模型之间建立桥梁，并为实验三营养系统的机制解释做出贡献。3. 为了开发适应性食物网模块，以反映浮游生物食物网的自然复杂性所产生的特性和动态，我们将把我们最近从更抽象的模型中获得的见解与康斯坦斯湖的全面数据结合起来。这也将有助于提高为特定生态系统量身定制的生物地球化学模型的真实感。为了用数据来面对已发展的理论，提高数学模型的真实性，我们将与该优先项目中的四个实验伙伴密切合作，将我们的模型应用于他们的数据。这将有助于优化实验设计，解释实验结果，并促进不同实验装置得出的结果之间的比较。执行一般任务，如促进DynaTrait内部的协同作用，例如撰写综合论文和教授暑期学校。预期的结果将促使人们重新考虑构成自然保护基础的基本生态学概念。

Trait variation within individuals, populations and communities allows them to adjust to altering environmental conditions, giving rise to biomass-trait feedbacks including eco-evolutionary dynamics. Using mathematical models, we will contribute to a unifying theory that explicitly considers how such feedbacks affect the structure and dynamics of predator-prey systems and more complex food webs. We postulate that (1) the standing trait variation (functional diversity) influences biomass and trait dynamics and (2) this, in turn, influences the maintenance of trait variation in concert with the trade-off(s) among traits. We will use four complementary model approaches: multispecies or multiclonal sorting models, full trait distribution models, aggregate models approximating full models by explicitly describing the dynamics of the mean and variance of the underlying trait distribution, and hybrid models considering intra- and interspecific trait variation simultaneously by combining a multispecies model with an aggregate approach. This enables us to investigate the intertwined ecological and evolutionary processes, and to test the robustness of our results against model assumptions. Our main objectives are:1. To synthesize current theory of biomass-trait feedbacks in bi-trophic food web models. We focus on (1) how different food web structures evolve by evolutionary diversification of prey and predators, and (2) how differences in structure, functional traits, trade-offs and sources of trait variation affect community dynamics, e.g. to explain unusual predator-prey dynamics. This includes considering a multi-dimensional trait space.2. To extend our models to tri-trophic systems including food chains and intra-guild predation, to bridge between more abstract but also more tractable predator-prey models, and more realistic complex food web models, and to contribute to mechanistic interpretations of experimental tri-trophic systems. 3. To develop adaptive food web modules reflecting properties and dynamics arising from the natural complexity of plankton food webs, we will combine our recent insights from our more abstract models with comprehensive data from Lake Constance. This will also help to improve the realism of biogeochemical models tailored to specific ecosystems.4. To confront the developed theory with data and improve the realism of the mathematical models, we will closely cooperate with four experimental partners within this priority program by applying our models to their data. This will help optimizing the experimental designs, interpreting the experimental results, and facilitating the comparison among findings derived from different experimental set-ups.5. To execute general tasks such as promoting synergies within DynaTrait, e.g. by leading synthesis papers, and teaching summer schools. The anticipated results will stimulate a reconsideration of concepts in fundamental ecology that form the basis for nature conservation.