物種之間的合作傾向于導致形成具有一個嵌套結(jié)構(gòu)的互助網(wǎng)絡。雖然嵌套性可能會增加生物多樣性和持久性,，但理論工作表明，嵌套網(wǎng)絡往往沒有非結(jié)構(gòu)化網(wǎng)絡穩(wěn)定,。這篇論文通過分析表明,，嵌套網(wǎng)絡是由一個能使互助群落中物種豐富度最大化的機制形成的，嵌套物種的豐富度與群落的可塑性直接相關(guān),。這項工作為研究生態(tài)因素和演化歷史怎樣形成生態(tài)網(wǎng)絡提供了一個模型,。（生物谷Bioon.com）
生物谷推薦英文摘要：
Nature doi: 10.1038/nature12438
Emergence of structural and dynamical properties of ecological mutualistic networks
Samir Suweis,Filippo Simini,Jayanth R. Banavar & Amos Maritan
Mutualistic networks are formed when the interactions between two classes of species are mutually beneficial. They are important examples of cooperation shaped by evolution. Mutualism between animals and plants has a key role in the organization of ecological communities. Such networks in ecology have generally evolved a nested architecture independent of species composition and latitude; specialist species, with only few mutualistic links, tend to interact with a proper subset of the many mutualistic partners of any of the generalist species1. Despite sustained efforts to explain observed network structure on the basis of community-level stability or persistence, such correlative studies have reached minimal consensus. Here we show that nested interaction networks could emerge as a consequence of an optimization principle aimed at maximizing the species abundance in mutualistic communities. Using analytical and numerical approaches, we show that because of the mutualistic interactions, an increase in abundance of a given species results in a corresponding increase in the total number of individuals in the community, and also an increase in the nestedness of the interaction matrix. Indeed, the species abundances and the nestedness of the interaction matrix are correlated by a factor that depends on the strength of the mutualistic interactions. Nestedness and the observed spontaneous emergence of generalist and specialist species occur for several dynamical implementations of the variational principle under stationary conditions. Optimized networks, although remaining stable, tend to be less resilient than their counterparts with randomly assigned interactions. In particular, we show analytically that the abundance of the rarest species is linked directly to the resilience of the community. Our work provides a unifying framework for studying the emergent structural and dynamical properties of ecological mutualistic networks.
