Minimal Spanning Tree (IMAGE) Max-Planck-Gesellschaft Caption The minimal spanning tree shows 59 genotypes (nodes) based on 88 genetic markers, whose continental sources are indicated by colors within pie-charts. Credit Philippe Roumagnac et al. Usage Restrictions None 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.