Diagram of stellar orbit statistics for CALIFA galaxies. The higher a galaxy's position, the larger that galaxy's fraction of hot (very elongated) orbits. The farther to the right a galaxy's position, the larger the fraction of cold (nearly circular) orbits. The fact that yellowish elliptical galaxies are mostly top left, while bluish disk galaxies are mostly bottom right indicates the link between stellar orbit statistics and a galaxy's history. Credit: CALIFA-Team / L. Zhu (MPIA)