2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/13172Semi-analytical models of galaxy formation based on hierarchical clustering now make a wide range of predictions for observable properties of galaxies at low and high redshift. This article concentrates on 2 aspects: (1) Self-consistent modelling of dust absorption predicts a mean UV extinction A_{UV} ~ 1 mag, depending only weakly on redshift, and similar to observational estimates. (2) The models predict that the Lyman-break galaxies found at z ~ 3 should be strongly clustered with a comoving correlation length r_0 = 4-7 Mpc/h (depending on the cosmology), in good agreement with subsequent observational determinations.5 pages, 3 figures. To appear in Proceedings of the MPA/ESO Conference "Evolution of Large-scale Structure: from Recombination to Garching", ed. A.J. Banday et alAstrophysicstext