title: Geographical variation in egg mass and egg content in a passerine bird.
abstract: Reproductive, phenotypic and life-history traits in many animal and plant taxa show geographic variation, indicating spatial variation in selection regimes. Maternal deposition to avian eggs, such as hormones, antibodies and antioxidants, critically affect development of the offspring, with long-lasting effects on the phenotype and fitness. Little is however known about large-scale geographical patterns of variation in maternal deposition to eggs. We studied geographical variation in egg components of a passerine bird, the pied flycatcher (Ficedula hypoleuca), by collecting samples from 16 populations and measuring egg and yolk mass, albumen lysozyme activity, yolk immunoglobulins, yolk androgens and yolk total carotenoids. We found significant variation among populations in most egg components, but ca. 90% of the variation was among individuals within populations. Population however explained 40% of the variation in carotenoid levels. In contrast to our hypothesis, we found geographical trends only in carotenoids, but not in any of the other egg components. Our results thus suggest high within-population variation and leave little scope for local adaptation and genetic differentiation in deposition of different egg components. The role of these maternally-derived resources in evolutionary change should be further investigated.
authors: Section of Ecology, Department of Biology, University of Turku, Turku, Finland. suvi.ruuskanen@utu.fi
authors: Suvi
authors: S
authors: Ruuskanen
authors: Heli
authors: H
authors: Siitari
authors: Tapio
authors: T
authors: Eeva
authors: Eugen
authors: E
authors: Belskii
authors: Antero
authors: A
authors: Järvinen
authors: Anvar
authors: A
authors: Kerimov
authors: Indrikis
authors: I
authors: Krams
authors: Juan
authors: J
authors: Moreno
authors: Chiara
authors: C
authors: Morosinotto
authors: Raivo
authors: R
authors: Mänd
authors: Erich
authors: E
authors: Möstl
authors: Markku
authors: M
authors: Orell
authors: Anna
authors: A
authors: Qvarnström
authors: Juha-Pekka
authors: JP
authors: Salminen
authors: Fred
authors: F
authors: Slater
authors: Vallo
authors: V
authors: Tilgar
authors: Marcel E
authors: ME
authors: Visser
authors: Wolfgang
authors: W
authors: Winkel
authors: Herwig
authors: H
authors: Zang
authors: Toni
authors: T
authors: Laaksonen
mesh_terms: D000818:Animals; D001947:Breeding; D019143:Evolution, Molecular; D056084:Genetic Fitness; D005843:Geography; D010063:Ovum / Q000254:growth & development* / Q000378:metabolism*; D046109:Passeriformes / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism*; D010641:Phenotype; D012641:Selection, Genetic