The beta diversity of the endosymbionts and non-endosymbionts differed with respect to location. Although non-endosymbionts demonstrated a small association with location, geographic association was not observed by the Rickettsia and Francisella endosymbionts. In addition, Procrustes analysis results demonstrated that Rickettsia and FLE beta diversities had different relationships to geographical locations than the other microbiome components, illustrating that different factors shape Rickettsia and FLE components of the D. occidentalis microbiome than other non-endosymbiont microbiome members. One factor that appeared to contribute to the geographical differences in the non-endosymbiont microbiome was isolation by distance. Geographical differences in bacterial community composition in the same hematophagous insect species has been seen in fleas and ticks, however, the causes are not completely known (Jones, Knight & Martin, 2010; Van Treuren et al., 2015). Differential geographic localization of Nevskia, Curtobacterium and Sphingomonas, genera that are associated with environmental sources such as the air-water interface (Nevskia) and soils (Curtobacterium and Sphingomonas), may be the result of differences in soil microbial ecology at each location (Van Treuren et al., 2015). Alternatively, non-endosymbiont microbiome differences could be the result of stochastic or different populations of ticks at each location. In contrast, the dependency of Rickettsia and Francisella endosymbionts on their D. occidentalis host may have restricted the degree of variation that population separation could impart upon these endosymbionts (Budachetri et al., 2014).