Animal and Plant Species in Antagonistic and Mutualistic Networks, a Multispecies Mean Field Model

Abstract

We construct a dynamic system model of a web of animal species interacting with plant species using a system of coupled differential equations. The model has a parameter which represents the effect of animal on plant species that can be positive (mutualistic interaction) or negative (antagonistic interaction). We work a Multispecies Mean Field Model MMFM in which the full set of and variables are reduced to a couple of an average animal and plant species. We study the conditions for existence of the MMFM and relate the result to the difference between animal and plant species in the network. We compare our results with empirical data from pollinators (mutualistic) and herbivorous insect (antagonistic) networks. We conclude by combining analytical and empirical work that antagonistic networks present fewer animal species in relation to plant species than mutualistic ones.