Pérez González, Pablo GuillermoAlonso Herrero, AlmudenaDonley, JenniferRieke, GeorgeBarro, GuillermoGallego Maestro, JesúsZamorano Calvo, Jaime2023-06-202023-06-202010978-3-642-11249-210.1007/978-3-642-11250-8_68https://hdl.handle.net/20.500.14352/45747© Springer-Verlag Berlin Heidelberg 2010. Scientific Meeting of the Spanish-Astronomical-Society (SEA) (8th. 2008. Santander/Spain).We present the latest results of the Spitzer Cosmological Surveys concerning the characterization of the evolution of galaxies in the last 12 Gyr (from z=4). We have analyzed the stellar mass function up to z=4 using a sample of more the 28,000 galaxies selected in the rest-frame near-infrared with Spitzer/IRAC. Our results confirm and quantify the “downsizing” scenario of galaxy formation. Based on the study of the specific SFRs of X-ray emitters, we discuss the role of AGN in the evolution of galaxies, arguing against the link between nuclear activity and the quenching of the star formation in massive galaxies at z<1.4.engbook parthttp://dx.doi.org/10.1007/978-3-642-11250-8_68https://link.springer.com/open access52AstronomyAstrophysicsAstrofísicaAstronomía (Física)