In this contribution, I present a simplified overview of the evolution of the
disk galaxy population since z=1, and a brief discussion of a few open
questions. Galaxy evolution surveys have found that the disk galaxy population
forms stars intensely at intermediate redshift. In particular, they dominate
the cosmic star formation rate at z<1 -- the factor of ten drop in cosmic
average comoving star formation rate in the last 8 Gyr is driven primarily by
disk physics, not by a decreasing major merger rate. Despite this intense star
formation, there has been little change in the stellar mass density in disk
galaxies since z=1; large numbers of disk galaxies are being transformed into
non-star-forming spheroid-dominated galaxies by galaxy interactions, AGN
feedback, environmental effects, and other physical processes. Finally, despite
this intense activity, the scaling relations of disk galaxies appear to evolve
little. In particular, as individual galaxies grow in mass through the
formation of stars, they appear to grow in radius (on average, the population
grows inside-out), and they appear to evolve towards somewhat higher rotation
velocity (i.e., mass is added at both small and large radii during this
inside-out growth).Comment: Invited Review at the Vatican Symposium: Formation and Evolution of
Galaxy Disks, October 2007, proceeding editors Jose G. Funes, SJ and Enrico
M. Corsin