The current generation of look-back surveys has given fresh insight into the evolution of the disk galaxy population over the last 8 to 10 billion years. In this review, I discuss the evolution of the masses, sizes, and star formation rates of the disk galaxy population. The emerging picture is: i) evidence for the steady conversion of an important fraction of the disk galaxy population into red-sequence galaxies during the last eight billion years, ii) a dramatic ramping down of the star formation rates of disks by almost a factor of ten in that time, and iii) non-evolution of the disk galaxy scaling relations (i.e., the evolution which occurs moves galaxies nearly along the scaling relations).

I will present some new results on the evolution of the disk galaxy population out to redshift z~1, using a sample of ~110,000 COSMOS galaxies.

We review the status of current observations of the fundamental parameters of intermediate redshift (z<1.3) disk galaxies. Modern instrumentation enables detailed measurements of galaxy luminosity, morphology, kinematics and mass, in both optical and the infrared passbands. By studying well known star formation indicators, the internal velocity structure and star formation rates of galaxies can be traced through this entire redshift regime. The combination of throughput and optimum seeing conditions yields spectra which can be combined with high resolution multiband imaging to explore the evolution of galaxies of various morphologies, and to place constraints on current models of galaxy formation and star formation histories. Out to redshifts of unity, these data form a high redshift Tully-Fisher relation that spans four magnitudes and extends to well below L*, with no obvious change in shape or slope with respect to the local relation. A comparison of disk surface brightness between local and high redshift samples yields an offset in accordance with distance-dependent surface brightness selection effects, as can the apparent change in disk size with redshift for disks of a given mass. The effects of imaging and spectral selection are shown to be significant, dependent not only upon the broad-band luminosity and surface brightness of targets but also a strong function of emission line strength and spectral flux distributions. These results provide further evidence for modest increases in luminosity with lookback time for the bulk of the observed field spiral galaxy population.

The last decade of ever-larger, panchromatic surveys has provided tremendous observational resources for tracing the growth and evolution of galaxies at high redshift. Deep Spitzer surveys, in particular, are offering new insight into star formation, the growth of stellar mass, and energetics from active nuclei, while HST surveys provide the morphological information needed to discriminate disks, bulges, and chaotic, merger-induced “messes”. I will review recent work on galaxy growth spanning most of cosmic history, based on observations from many programs, including the GOODS and FIDEL Spitzer Legacy surveys, with an eye toward what we have and have not learned about the maturing structure of disk galaxies.

Keys to understanding the formation of local galaxy disks are observations of their properties as the universe ages. Such observations are currently being made by surveys of distant (z~1) galaxies. As such, we are now beginning to understand how the ancient morphologically disturbed proto-disks that were dominant in the early universe have evolved into the morphologically regular disks of today. Some of the most intriguing tracers of this evolution come from surveys that measure the kinematics of sizeable numbers of disk galaxies (~500 to >1000) over the last ~8 Gyrs (to z~1). They allow us to trace the fundamental scaling relations of disk galaxies (Tully-Fisher, size-velocity, size-mass), previously privy only to astronomers working in the local universe. We present these scaling relations from the DEEP2 galaxy survey and the AEGIS multi-wavelength collaboration. One intriguing result is that kinematic data show evidence for dynamical setting, while also revealing consistency in total potential well depth. We compare our observations to N-body simulations of dark matter halos from Diemand et al. (2007). This comparison gives insight into how the stellar and dark masses of galaxies grow, and how the kinematic properties of galaxies can inform us about their parent dark matter halos (and vice-versa).

We have conducted a systematic search for stellar disk truncations in disklike galaxies at intermediate redshift (z<1.1) using the Hubble Ultra Deep Field data. We use the position of the truncation as a direct estimator of the size of the stellar disk. After accounting for the surface brightness evolution of the galaxies, our results suggest that the radial position of the truncations has increased with cosmic time by ~1-3 kpc in the last ~8 Gyr. This result indicates a small to moderate (~25%) inside-out growth of the disk galaxies since z~1.

The z=2 epoch corresponds to the peak of the AGN activity and of the star formation rate density of the Universe. We have combined a large variety of the deepest multiwavelength datasets in the GOODS survey in order to unveil the properties of massive star-forming galaxies at this crucial epoch, that appear to be mostly disks and/or irregular galaxies. I will present our latest results on star formation diagnostics in the distant Universe, the implications on galaxy growth and the constraints on concurrent AGN activity in these galaxies. We have unveiled a new and large population of Compton thick AGN, with implications on the coeval growth of galaxies and bulges and the X-ray background. I will present our new results from PdBI observations of redshifted CO lines that support a major role of accretion for the buildup of the mass in today's most massive galaxies.

How well do we understand the origin of the well-known scaling relations between stellar mass, radial size, and internal velocity in galactic disks? How well do state-of-the-art LCDM galaxy formation models reproduce these scaling relations, and are they consistent with other observations such as the stellar mass function and luminosity function? Deep multiwavelength surveys have recently shown that size-mass and velocity-mass relations for disks have evolved very little since z~1, and that large, rapidly rotating disks are present in perhaps surprisingly large numbers even at z~2. This is in conflict with the simplest predictions from theory, which predict more rapid evolution. I will argue that this tension can be resolved by taking into account the hierarchical build-up of dark matter halo profiles, as predicted by LCDM simulations. Finally, I will discuss the implications of this improved modeling of disk structure for the efficiency of star formation at high redshift.

I will present preliminary results of an ESO-VLT large programme aimed at investigating the mass-metallicity relation at z>3, by means of integral field near-IR spectroscopic observations. Some of the objects in our sample present morphological and dynamical properties suggesting that these are galaxy disks in formation. I will discuss the properties of such primoridial disks, by focusing on their metallicity. In some cases we also detect a clear metallicity gradient. I will compare our observational results with the expectations from the various models of chemical evolution of galaxy disks.

We performed multi-color, two-dimensional, PSF-convolved bulge+disk decompositions on a sample of 400,000 galaxies from the Sloan Digital Sky Survey Data Release 4 spectroscopic sample and study the galaxy disk luminosity-size relation at z=0.1. The resulting relation exhibits striking features that indicate that some disks are in fact produced through angular momentum transfer in major merger events.