Fig. 1

Proportion of species and infection frequencies binned in 10 % intervals. Black bars describe the observed infection frequencies within samples from each of the 312 species. For these data, the bin boundaries are treated as upper bounds (so a sample prevalence of exactly 10 % would be placed in the 0-10 % category). Dark grey bars describe the expected proportion of species infected under best-fit beta distribution as estimated by Maximum Likelihood (Table 2), and the best-fit pdf (eq. 3, with ML parameter estimates α = 0.24 and β = 0.63, scaled for visualization) is also shown for comparison. The light grey bars show the expected proportion of species under the parameter estimates of Hilgenboecker et al. [11] for their ‘B(iii)’ arthropod data set