compilation and network analyses of cambrian food webs编译和寒武纪食物网的网络分析.pdf

PLoS BIOLOGY Compilation and Network Analyses of Cambrian Food Webs Jennifer A. Dunne1,3*, Richard J. Williams2,3, Neo D. Martinez3,4, Rachel A. Wood5,6, Douglas H. Erwin1,7 1 Santa Fe Institute, Santa Fe, New Mexico, United States of America, 2 Microsoft Research Limited, Cambridge, United Kingdom, 3 Pacific Ecoinformatics and Computational Ecology Lab, Berkeley, California, United States of America, 4 National Center for Ecological Analysis and Synthesis, Santa Barbara, California, United States of America, 5 Grant Institute, School of GeoSciences, University of Edinburgh, Edinburgh, United Kingdom, 6 Edinburgh Collaborative of Subsurface Science and Engineering, University of Edinburgh, Edinburgh, United Kingdom, 7 Department of Paleobiology, National Museum of Natural History, Washington, D.C., United States of America A rich body of empirically grounded theory has developed about food webs—the networks of feeding relationships among species within habitats. However, detailed food-web data and analyses are lacking for ancient ecosystems, largely because of the low resolution of taxa coupled with uncertain and incomplete information about feeding interactions. These impediments appear insurmountable for most fossil assemblages; however, a few assemblages with excellent soft-body preservation across trophic levels are candidates for food-web data compilation and topological analysis. Here we present plausible, detailed food webs for the Chengjiang and Burgess Shale assemblages from the Cambrian Period. Analyses of degree distributions and other structural network properties, including sensitivity analyses of the effects of uncertainty associated with Cambrian diet designati