The evolutionary significance of the geometric increased in prevalence of a specific disease, a form of inflammatory arthritis referred to as spondyloarthropathy, suggests either an as yet undetermined organismal benefit or an increase in environmental contamination. Recognized on the basis of sacroiliac joint pathology, the character and prevalence were assessed in Rhinoceridae in North American, European and Asian paleontological collections. Bemalambda had identical pathology to that found in Corythodon. Sacroiliac fusion was noted in seven Plesiaceratherium gracile and in two Coelodonta antiquitatis. Miocene and Pleistocene occurrence in Europe and Asia revealed the identical trend to that noted in North America. Given the independent occurrence (Europe/Asia and North America) and parallel increase in population penetrance of spondyloarthropathy through geologic time and evidence from contaminated human sites, the results provides a window to an environmental exposure problem that has exacerbated over geologic time.