title: Evolution of seasonal transmission patterns in avian blood-borne parasites.
abstract: In temperate regions, many vector-borne parasites maximise their transmission prospects by adjusting reproduction to seasonal cycles of host susceptibility and vector availability. Nevertheless, in these regions there are areas where environmental conditions are favourable throughout the year, so that parasites could benefit from a year-round transmission strategy. We analysed how different transmission strategies (strict summer transmission, extended summer transmission - including spring and autumn, and year round transmission) have evolved among the different genetic lineages of Haemoproteus parabelopolskyi, an avian blood-borne parasite shared by three sibling species of passerine hosts. Our results indicate that the ancestral state of this clade of parasites had a strict summer transmission with the blackcap (Sylvia atricapilla) as the host. Other transmission strategies and switches to the other host species (Sylvia abyssinica and Sylvia borin) evolved recently, several times, independently. This suggests that, although year-round transmission is ecologically successful at present, seasonal transmission may have become more stable over evolutionary time. Switches from strict summer to an extended or year-round transmission strategy could have ecological consequences, if they promote the spread of parasites into more distant regions, transported by the migrating bird hosts. Therefore, a deeper knowledge of how different parasite transmission strategies are structured among birds in temperate areas is essential for understanding how disease emergence risks may develop in the future.
authors.affiliation: Departamento de Zoología y Antropología Física, Universidad Complutense de Madrid, José Antonio Nováis 2, E-28040 Madrid, Spain. Electronic address: adperez@bio.ucm.es.
authors.forename: Antón
authors.initials: A
authors.lastname: Pérez-Rodríguez
authors.affiliation: Departamento de Zoología y Antropología Física, Universidad Complutense de Madrid, José Antonio Nováis 2, E-28040 Madrid, Spain.
authors.forename: Iván
authors.initials: I
authors.lastname: de la Hera
authors.affiliation: Department of Biology, Lund University, Sölvegatan 37, 223 62 Lund, Sweden.
authors.forename: Staffan
authors.initials: S
authors.lastname: Bensch
authors.affiliation: Departamento de Zoología y Antropología Física, Universidad Complutense de Madrid, José Antonio Nováis 2, E-28040 Madrid, Spain.
authors.forename: Javier
authors.initials: J
authors.lastname: Pérez-Tris
mesh_terms: D000818:Animals; D016782:Apicomplexa / Q000235:genetics*; D005075:Biological Evolution; D001715:Bird Diseases / Q000097:blood / Q000469:parasitology*; D008969:Molecular Sequence Data; D010273:Parasitic Diseases, Animal / Q000469:parasitology*; D046109:Passeriformes; D010802:Phylogeny; D012621:Seasons; D013997:Time Factors
keywords: Ancestral state reconstruction; Haemoproteus parabelopolskyi; Host switching; Parasite relapse; Parasite transmission seasonality; Sylvia atricapilla