Central surface brightness (top) and disk scale lengths (bottom) versus absolute magnitudes in intervals of 1 Gyr compared to irregular dwarf galaxies (black), blue compact dwarfs (dark blue), and Magellanic spirals (gray) from Hunter & Elmegreen (2006). Note that the stellar mass grows (mostly in the center) and so the magnitude and disk scale length decreases and the central surface brightness increases during the simulations.