2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/122227Replacement of papers q-bio/0605026 and q-bio/0607043 by a single manuscript (q-bio/0701029) follows suggestions from a magazine's refereeThis paper, together with paper q-bio/0607043 are replaced by q-bio/0607043Populations and EvolutionNestedness in mutualistic networks emerges from a modified rule of preferential attachmenttext