Host repertoire
Most species of Cichlidogyrus had a higher structural specificity
than expected at random as their di’ estimates often
significantly exceeded the respective null distributions (Appendix S5).
For the phylogenetic specificity, differences to the null models were
less often significant but in case of significant differences, host
meta-communities were clustered at the level of mean pairwise distance
(MPD) or MPD and mean nearest taxon distance (MNTD) (Appendix S5).
Functional-phylogenetic distances (FPDist) were calculated for all
species of Cichlidogyrus with more than one host species
(Appendix S6) with the weighting parameter a between 0 and 1.
Plots for some species are shown in Fig. 4 to illustrate the main
patterns observed across all species. Generally, FPDist decreased with
increasing phylogenetic weight (MPD or MNTD) as indicated by the falling
trend of FPDist estimates (Fig. 4). Observed MPD and MNTD showed a
significant pattern of underdispersion compared to 1000 random
simulations in some cases. Specifically, MPD metrics of FPDist became
mostly significant if the weight of phylogenetic distances (PDist)
increased (i.e. a → 1) (Fig. 4). In contrast, MNTD estimates were
largely non-informative regardless of a . One exception to these
observation is Cichlidogyrus sp. ‘nyanza’ (Gobbin et al.2021) with MNTD estimates being lowest for a → 0 (Fig. 4).