Star cluster distributions of NGC 2915. Top: distribution of star clusters in the mass–age plane. The plotted mass is the mass at birth. Each circle is a star cluster color-coded by its metallicity. The purple solid curve is the 90% mass completeness limit converted from the V = 22.8 mag brightness limit by using age-dependent mass-to-light ratios. The purple dashed line is plotted as a guide for the expected relation between maximum cluster mass and age by assuming a fiducial cluster mass function and constant cluster formation history. The dynamical evaporation limit is derived using a galactocentric radius of 0.47 kpc (24 arcsec) and a rotation velocity of 15 km s⁻¹, as appropriate for the inner disk of NGC 2915. Bottom: spatial distribution of star clusters color-coded by the stellar age. The filled circles are plotted with sizes proportional to the fourth root of stellar mass. The EW(Hα) distribution is overplotted as contours.