Summary of Results (IMAGE) Max Planck Institute of Geoanthropology Caption Schematic summary of the results of analyses. Boxes indicate a significant correlation between variables and parasite load. As more statistical controls are added, all the relationships proposed in previous research become spurious artefacts. Credit Bromham et al. 2018. Parasites and politics: why cross-cultural studies must control for relatedness, proximity and covariation. <em>Royal Society Open Science</em>, DOI: 10.1098/rsos.181100. Usage Restrictions This image may only be used in the context of reporting on this publication and with appropriate credit information. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.