  Stars in globular clusters (GCs) exhibit a peculiar chemical pattern with
strong abundance variations in light elements along with a constant abundance
in heavy elements. These abundance anomalies can be explained by a primordial
pollution due to a first generation of fast rotating massive stars which
released slow winds into the ISM from which a second generation of chemically
anomalous stars can be formed. In particular the observed ratio of anomalous
and standard stars in clusters can be used to constrain the dynamical evolution
of GCs as around 95% of the standard stars need to be lost by the clusters. We
show that both residual gas expulsion during the cluster formation and long
term evolution are needed to achieve this ratio.
