title: Pathogen-induced rapid evolution in a vertebrate life-history trait.
abstract: Anthropogenic factors, including climate warming, are increasing the incidence and prevalence of infectious diseases worldwide. Infectious diseases caused by pathogenic parasites can have severe impacts on host survival, thereby altering the selection regime and inducing evolutionary responses in their hosts. Knowledge about such evolutionary consequences in natural populations is critical to mitigate potential ecological and economic effects. However, studies on pathogen-induced trait changes are scarce and the pace of evolutionary change is largely unknown, particularly in vertebrates. Here, we use a time series from long-term monitoring of perch to estimate temporal trends in the maturation schedule before and after a severe pathogen outbreak. We show that the disease induced a phenotypic change from a previously increasing to a decreasing size at maturation, the most important life-history transition in animals. Evolutionary rates imposed by the pathogen were high and comparable to those reported for populations exposed to intense human harvesting. Pathogens thus represent highly potent drivers of adaptive phenotypic evolution in vertebrates.
authors.affiliation: Centre for Ecological and Evolutionary Synthesis (CEES), Department of Biology, University of Oslo, PO Box 1066 Blindern, 0316 Oslo, Norway. jan.ohlberger@bio.uio.no
authors.forename: Jan
authors.initials: J
authors.lastname: Ohlberger
authors.forename: Øystein
authors.initials: Ø
authors.lastname: Langangen
authors.forename: Eric
authors.initials: E
authors.lastname: Edeline
authors.forename: Esben Moland
authors.initials: EM
authors.lastname: Olsen
authors.forename: Ian J
authors.initials: IJ
authors.lastname: Winfield
authors.forename: Janice M
authors.initials: JM
authors.lastname: Fletcher
authors.forename: J Ben
authors.initials: JB
authors.lastname: James
authors.forename: Nils Christian
authors.initials: NC
authors.lastname: Stenseth
authors.forename: Leif Asbjørn
authors.initials: LA
authors.lastname: Vøllestad
mesh_terms: D000818:Animals; D005075:Biological Evolution; D049628:Body Size; D004739:England / Q000453:epidemiology; D005393:Fish Diseases / Q000453:epidemiology* / Q000382:microbiology*; D016015:Logistic Models; D008137:Longitudinal Studies; D009181:Mycoses / Q000453:epidemiology / Q000662:veterinary*; D010471:Perches; D010641:Phenotype; D012741:Sexual Maturation / Q000502:physiology*; D013997:Time Factors