The roughly factor of ten decline in the star
formation rate of the universe over the last 8 billion years has
contributed to a change in the optical and infrared properties of
galaxies. Luminous infrared galaxies (LIRGs), rare locally,
contribute 70% of the IR energy density of the universe at z=1, and
therefore account for a significant fraction of the SFR density
decline since then. We find that in GOODS-N, above z=0.5 roughly half
of LIRGs are spirals. Whereas the rare low-z LIRGs are dominated by
mergers. We also find that the IR evolution of GOODS-N galaxies is
accompanied by an optical luminosity decline, consistent with an
exponential decline in the SFR with an e-folding time of 3 Gyr.
Finally, we demonstrate how a combination of high resolution adaptive
optics and Hubble space telescope images may reveal the sites of
significant star formation in distant LIRG disks and teach us about
the triggers of star formation at z=1.