Thus, it appears that diversification of seabird lineages do not provide greater opportunities for increasing parasite species richness, unlike studies of host diversification in primates that found a strong positive relationship between parasite richness and host diversification [ 3].
A positive relationship was documented between nestedness (N) and species richness of ectoparasite-vertebrate host networks (R2 = 0.417; F = 18.777; p<0.0005).
To investigate the effect of species diversity on hantavirus infection we carried out an experimental study of the small mammal community in the Azuero Peninsula in Panama, manipulating the species richness and population densities of host and non-host species in experimental plots at edges of small forest fragments.
By applying a variant of independent contrast analysis, specially tailored for use on questions of species richness (MacroCAIC), we show that species richness is strongly correlated with diversity of host use in the butterfly family Nymphalidae.
This view, however, has been recently challenged by a meta-analysis [ 20], whose results suggest that host body size, geographical range size, and population density should be considered as universal predictors of parasite richness across host species.
The correlation between diversity of host use and species richness was tested with the computer program MacroCAIC [ 45], which applies the method of independent contrasts to questions of species richness.
To test this hypothesis, we have performed an independent contrast analysis to look for a general phylogenetic correlation between diversity of host plants and species richness.
Furthermore, by comparing the results from reciprocal sister group selection, where sister groups were selected either on the basis of diversity of host use or species richness, we find that it is likely that diversity of host use is driving species richness, rather than vice versa.
In the second case we would conclude that, even though species richness cannot be the only factor that influences patterns of host diversity, when we do have an increase in species richness, it seems to trigger an increase in host diversity.
It is a story of great complexity and richness, with a host of brilliantly executed character portrayals and a profound understanding of human strengths and weaknesses.
