Figure 1.

Two empirical patterns in the evolution of host–parasite associations.

Each pattern is given as a tanglegram. Different intensities of shading represent different lineages for host and parasite phylogenies. The codivergence event is indicated using matching circles. The lower-case letters represent a “species,” and the numbers next to lower-case letters an “intraspecific lineage”; upper-case letter represent a “supra-specific group,” for example, genus, tribe, subfamily, and family. Type I Codivergence—The divergence of 6 intraspecific lineages of 2 parasitic species (lower-case letters “a” and “b” within square) occurs in response to the speciation events of its hosts. Type II Codivergence—The divergence of 3 intraspecific lineages of parasitic species “a” occurs in response to the speciation events of its hosts (at level supra-specific, capital letters A, B, and C within square), and subsequent colonisation (via host-switch) of parasite lineages to new hosts with monophyletic affinities, for example, the taxon hosts included in A (a, b, and c), is associated with the parasite lineage “a1” (different cophylogenetical hypothetical pattern can be revised from Page 1994b; Ronquist 2003; de Vienne et al. 2013).