Fig. 2

Modular simplification of the interaction network showing statistical significance in the phylogenetic module structure. A network module can be defined as a group of nodes that shares more links within them than with nodes from other modules. In the figure, a module is represented by an ellipse containing icons of a gyrodactylid and a fish. Panel A: six modules that were formed by phylogenetically clustered gyrodactylids have red circles, and others have black circles. Panel B: after accounting for geography, none of the modules exhibited a significant phylogenetic clustering. The module number is displayed in the circle. Gray lines represent the edges of the interaction network