title: Mate preference of female blue tits varies with experimental photoperiod.
abstract: Organisms use environmental cues to time their life-cycles and among these cues, photoperiod is the main trigger of reproductive behaviours such as territory defence or song activity. Whether photoperiod is also important for another behaviour closely associated with reproduction, mate choice, is unknown. In many bird species, mate choice occurs at two different times during the annual cycle that strongly differ in daylength: in late winter when photoperiod is short and social mates are chosen, and again around egg-laying when photoperiod is longer and extra-pair mates are chosen. This duality makes the role that photoperiod plays on mate choice behaviours intriguing. We investigated the effect of photoperiod on mate choice using three experimental photoperiodic treatments (9 L:15 D, 14 L:10 D, 18 L:6 D), using blue tits (Cyanistes caeruleus) as a biological model. We show that female choice was stronger under long photoperiods. In addition, female blue tits spent significantly more time near males with long tarsi and long wings. This latter preference was only expressed under long photoperiods, suggesting that some indices of male quality only become significant to females when they are strongly photostimulated, and therefore that females could select their social and extra-pair mates based on different phenotypic traits. These results shed light on the roles that photoperiod may play in stimulating pair-bonding and in refining female selectivity for male traits.
authors.affiliation: Department of Animal Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Wageningen, The Netherlands; Behavioural Ecology Group, Department of Animal Sciences, Wageningen University (WUR), The Netherlands.
authors.forename: Laura B
authors.initials: LB
authors.lastname: Reparaz
authors.affiliation: Department of Animal Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Wageningen, The Netherlands.
authors.forename: Kees
authors.initials: K
authors.lastname: van Oers
authors.affiliation: Behavioural Ecology Group, Department of Animal Sciences, Wageningen University (WUR), The Netherlands.
authors.forename: Marc
authors.initials: M
authors.lastname: Naguib
authors.affiliation: Department of Evolutionary Ecology, CEFE-CNRS, Montpellier, France.
authors.forename: Claire
authors.initials: C
authors.lastname: Doutrelant
authors.affiliation: Department of Animal Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Wageningen, The Netherlands.
authors.forename: Marcel E
authors.initials: ME
authors.lastname: Visser
authors.affiliation: Department of Animal Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Wageningen, The Netherlands; Department of Evolutionary Ecology, CEFE-CNRS, Montpellier, France.
authors.forename: Samuel P
authors.initials: SP
authors.lastname: Caro
mesh_terms: D000818:Animals; D001717:Birds / Q000502:physiology*; D005260:Female; D008297:Male; D052586:Mating Preference, Animal / Q000502:physiology*; D009929:Organ Size; D017440:Photoperiod; D019655:Quantitative Trait, Heritable; D014921:Wings, Animal / Q000033:anatomy & histology