  Observational and theoretical arguments support the idea that violent events
connected with $AGN$ activity and/or intense star forming episodes have played
a significant role in the early phases of galaxy formation at high red shifts.
Being old stellar systems, globular clusters seem adequate candidates to search
for the eventual signatures that might have been left by those energetic
phenomena. The analysis of the colour distributions of several thousands of
globular clusters in the Virgo and Fornax galaxy clusters reveals the existence
of some interesting and previously undetected features. A simple pattern
recognition technique, indicates the presence of "colour modulations",
distinctive for each galaxy cluster. The results suggest that the globular
cluster formation process has not been completely stochastic but, rather,
included a significant fraction of globulars that formed in a synchronized way
and over supra-galactic spatial scales.
