Evolutionary Studies of Galaxies at Intermediate Redshifts

Abstract

Photometric and spectroscopic studies of cluster and field galaxies out to redshifts of -0·5 have provided clear evidence for strong evolution over recent epochs. The development of this picture is reviewed by contrasting and comparing the investigations of distant galaxies in rich clusters and the low density field. A common link is found in that the evolution of galaxies in both environments is related to short-lived bursts of star formation. The triggering mechanism for these bursts is discussed with special attention being paid to the role of galaxy merging