Conventional Wisdom Revised in Terms of a Diversity-Uncertainty Model for the Effect of Host Genetic Diversity on...

Developing 'conventional wisdom' that less genetically diverse host populations tend to experience larger epidemics on average, I re-analyse 211 effect sizes from outside of the plant literature to investigate my Diversity-Uncertainty model. By combining unduplicated effect sizes from Ekroth et al. 2019 (67) and Gibson and Nguyen 2020 (155, total 211), I find evidence to suggest that an epidemic's size (via 'parasite success') is influenced by a combination of the genetic diversity of not only host, but also parasite populations. Additionally, I argue that conventional wisdom could be reframed because it only seems to apply to parasites where their host range is narrow (1 species) compared with those with a relatively broader host range (> 1 species). The impact of these results is relevant for predicting the occurrence of particularly large and severe epidemics.