Fig. 4

Strongyle species co-occurrence networks inferred from necropsy data collected in France. Networks represent species pair-wise association matrix estimated with the hierarchical species distribution model applied to worm counts collected in Normandy, France (n = 36 necropsied horses). Each species is represented as a node whose size is proportional to the species mean relative abundance (c, d) or mean prevalences (a, b) in the population. Edges indicate correlation with 95% posterior support (in occurrence for a, b; in abundance for c, d) with another species (pale brown if positive, green otherwise). The left panels (a, c) were drawn from the raw correlations and the right panels (b, d) were built from the residual correlation estimates obtained after accounting for variability in the total worm burden, horse age, anatomical niche and inter-horse variation. Node sizes are proportional to the species mean relative abundance (c, d) or mean prevalence (a, b) in the population