Probing galaxy evolution using Globular Clusters and their integrated broad band colors

Color-color distributions of extragalactic globular cluster systems are widely used to resolve stellar populations within their parent galaxies. However, the color predictions of the various SSP models differ significantly, resulting in model dependent age and metallicity estimates for the different stellar populations. Given that those constrain the formation and evolution of the host galaxy, this model dependency has to be removed from the analysis or quantified. Here we compare the cumulative age distributions as derived from Monte-Carlo simulations and based on various SSP models with each other and use them to derive the age structure in globular cluster systems in early-type galaxies.