title: A quantitative genetic signature of senescence in a short-lived perennial plant.
abstract: The evolution of senescence (the physiological decline of organisms with age) poses an apparent paradox because it represents a failure of natural selection to increase the survival and reproductive performance of organisms. The paradox can be resolved if natural selection becomes less effective with age, because the death of postreproductive individuals should have diminished effects on Darwinian fitness [1, 2]. A substantial body of empirical work is consistent with this prediction for animals, which transmit their genes to progeny via an immortal germline. However, such evidence is still lacking in plants, which lack a germline and whose reproduction is diffuse and modular across the soma. Here, we provide experimental evidence for a genetic basis of senescence in the short-lived perennial plant Silene latifolia. Our pedigree-based analysis revealed a marked increase with age in the additive genetic variance of traits closely associated with fitness. This result thus extends to plants the quantitative genetic support for the evolutionary theory of senescence.
authors.affiliation: Laboratoire Evolution and Diversité Biologique, CNRS, Université Paul Sabatier, ENFA, UMR5174 EDB, 118 Route de Narbonne, 31062 Toulouse, France; UMR5174 EDB, Université de Toulouse, 31062 Toulouse, France. Electronic address: benoit.pujol@univ-tlse3.fr.
authors.forename: Benoit
authors.initials: B
authors.lastname: Pujol
authors.affiliation: Laboratoire Evolution and Diversité Biologique, CNRS, Université Paul Sabatier, ENFA, UMR5174 EDB, 118 Route de Narbonne, 31062 Toulouse, France; UMR5174 EDB, Université de Toulouse, 31062 Toulouse, France; Département de Biologie, Faculté des Sciences, Université de Sherbrooke, Sherbrooke, QC J1K 2R1, Canada.
authors.forename: Pascal
authors.initials: P
authors.lastname: Marrot
authors.affiliation: Department of Ecology and Evolution, University of Lausanne, 1015 Lausanne, Switzerland.
authors.forename: John R
authors.initials: JR
authors.lastname: Pannell
mesh_terms: D016922:Cellular Senescence / Q000235:genetics*; D017343:Genes, Plant; D014644:Genetic Variation; D008136:Longevity / Q000235:genetics; D012641:Selection, Genetic; D029751:Silene / Q000235:genetics* / Q000254:growth & development