Particularity of “Universal resilience patterns in complex networks”

In a recent Letter to Nature,Gao, Barzel and Barabasi 1 describe an elegant procedure to reduce the dimensionality of complex dynamical networks, which they claim reveals \"universal patterns of network resilience\", offering \"ways to prevent the collapse of ecological, biological or economic systems, and guiding the design of technological systems resilient to both internal failures and environmental changes\". However, Gao et al restrict their attention to systems for which all interactions between nodes are mutualistic. Since antagonism is ubiquitous in natural and social networks, we clarify why this stringent hypothesis is necessary and what happens when it is relaxed. By analyzing broad classes of competitive and predator-prey networks we provide novel insights into the underlying mechanisms at work in Gao et als theory, and novel predictions for dynamical systems that are not purely mutualistic.