The structure and robustness of ecological networks with two interaction types
Fig 5
The 4 different null models used in this study.
Each figure represents what is kept fixed in each null model, going from the less restrictive on the left, to the more restrictive on the right. Nx is the number of nodes in the species set, Lx the number of links in the interaction layer, the color of the nodes represent the different species set, the colour of the link the two different ecological interactions, the size of the node is proportional to its degree (when kept), and connector nodes are highlighted in red.