title: Directional selection effects on patterns of phenotypic (co)variation in wild populations.
abstract: Phenotypic (co)variation is a prerequisite for evolutionary change, and understanding how (co)variation evolves is of crucial importance to the biological sciences. Theoretical models predict that under directional selection, phenotypic (co)variation should evolve in step with the underlying adaptive landscape, increasing the degree of correlation among co-selected traits as well as the amount of genetic variance in the direction of selection. Whether either of these outcomes occurs in natural populations is an open question and thus an important gap in evolutionary theory. Here, we documented changes in the phenotypic (co)variation structure in two separate natural populations in each of two chipmunk species (Tamias alpinus and T. speciosus) undergoing directional selection. In populations where selection was strongest (those of T. alpinus), we observed changes, at least for one population, in phenotypic (co)variation that matched theoretical expectations, namely an increase of both phenotypic integration and (co)variance in the direction of selection and a re-alignment of the major axis of variation with the selection gradient.
authors.affiliation: Departamento de Genética e Biologia Evolutiva, Instituto de Biociências, Universidade de São Paulo, São Paulo, São Paulo 05508-090, Brazil paulaaprigio@usp.br.
authors.forename: A P A
authors.identifier: 0000-0001-8170-6352
authors.initials: AP
authors.lastname: Assis
authors.affiliation: Museum of Vertebrate Zoology, University of California at Berkeley, Berkeley, CA 94720, USA.
authors.forename: J L
authors.initials: JL
authors.lastname: Patton
authors.affiliation: Departamento de Oceanografia, Instituto de Geociências, Universidade Federal da Bahia, Salvador, Bahia 40170-020, Brazil.
authors.forename: A
authors.initials: A
authors.lastname: Hubbe
authors.affiliation: Departamento de Genética e Biologia Evolutiva, Instituto de Biociências, Universidade de São Paulo, São Paulo, São Paulo 05508-090, Brazil.
authors.forename: G
authors.initials: G
authors.lastname: Marroig
mesh_terms: D000818:Animals; D005075:Biological Evolution; D014644:Genetic Variation; D005828:Genetics, Population; D008957:Models, Genetic; D010641:Phenotype; D012589:Sciuridae / Q000145:classification*; D012641:Selection, Genetic
keywords: P-matrix; Tamias; adaptive landscape; chipmunks; genotype–phenotype map; quantitative genetics