Total infrared luminosity density produced at 1.5 < z < 1.9, 1.9 < z < 2.3 and 2.3 < z < 2.7 by 24 μm sources with F_24   μm > 0.08 mJy (black triangles), compared to the contribution of 24 μm sources identified with the selection techniques described in Sects. 3 and 4 (red: BzK; green: BM/BX; yellow: IRAC peakers; blue: OFIR galaxies with photo-z identification). For galaxy samples where the MIPS 24 μm emission is mostly produced by star formation (i.e., BzK and BM/BX soursces, IRAC peakers) the IR luminosity density can be read as a star formation density (right vertical axis) assuming the conversion from Kennicutt (1998). For comparison, the evolution of the total IR luminosity density inferred by Rodighiero et al. (2010) up to z ~ 2.5 is illustrated by the lightly shaded region. The cosmic star formation history derived by Hopkins & Beacom (2006) is represented by the dark shaded area. The typical uncertainty affecting our estimates is shown by the vertical line in the top left corner of the diagram.