Weighted individual-resource networks in prey–predator systems: the role of prey availability on the emergence of modular structures  

作　　者：Andrea COSTA Antonio ROMANO Giacomo ROSA Sebastiano SALVIDIO 

机构地区：[1]Department of Earth,Environment and Life Sciences(DISTAV),University of Genova,Genova,Italy [2]Italian National Research Council(CNR),Agriculture and Food Sciences Department(IBE),Institute of Bioeconomy–Biology,Roma,RM,Italy

出　　处：《Integrative Zoology》2022年第1期115-127,共13页整合动物学（英文版）

基　　金：by the Italian Ministry of Environment(DPN–2008–0008213 and PNM–II–2012–0015691);by the Prefecture of Haute Corse,France(2B–2018–01–92–004).

摘　　要：Ecological networks,usually depicting interactions among species,have been recently down-scaled to the individual level,permitting description of patterns of inter-individual resource variation that are usually hindered at the species level.Optimal diet theory(ODT)models,applied to prey–predator systems,predict different patterns of nestedness and modularity in the network,depending on the available resources and intra-specific competition.The effect of resource availability on the emergence of networks structures,and ODT framework,has not yet fully been clarified.Here,we analyzed the structural patterns of individual-resource networks in 3 species of Mediterranean salamanders,in relation to changes in prey availability.We used weighted individual-resource network metrics to interpret the observed patterns,according to 3 ODT models.We found significant nestedness recurring in our study system,indicating that both selective and opportunistic individuals occur in the same population.Prey diversity,rather than abundance,was apparently related to inter-individual resource variation and promoted the emergence of significant modularity within all networks.The observed patterns of nestedness and modularity,together with the variation in resource diversity and intra-specific competition,are in agreement with the distinct preferences model of ODT.These findings suggest that in the focal prey–predator systems,individuals were able to perceive changes in prey diversity and to exploit in different ways the variations in composition of available resources,shifting their diet assembly rules accordingly.Our findings also confirm that the use of weighted individual-resource networks,in prey–predator systems,allows to disclose dynamics that are masked at the species or population level.

关 键 词：inter-individual resource variation network-analysis optimal diet theory prey availability SALAMANDERS 

分 类 号：O17[理学—数学]