Richard Ellis

Caltech

          THE MASS ASSEMBLY HISTORY OF GALAXIES

Recent progress in unravelling the star formation history
of galaxies has demonstrated the importance of complementing such
information with estimates of the mass assembly history
central to distinguishing between `monolithic' and `hierarchical'
models of galaxy formation. Infrared photometry offers
the most direct route to estimating stellar masses
over a range in redshift and morphological type. Using this
and other diagnostic methods, I present new observational  
evidence for the growth rate of stellar disks, the continued
formation of spheroidal galaxies and discuss the likely cause
for the demise of faint blue irregulars.