title: Does coping style predict optimization? An experimental test in a wild passerine bird.
abstract: A number of studies have suggested that avian brood size is individually optimized. Yet, optimal reproductive decisions likely vary owing to among-individual differences in environmental sensitivity. Specifically, 'proactive' individuals who do not track environmental changes may be less able to produce optimal brood sizes than 'reactive' individuals who have more precise local environmental knowledge. To test this, we quantified exploratory behaviour (a proxy for proactivity) in a great tit (Parus major) population, manipulated brood sizes (reduced, control, enlarged) and evaluated whether individuals of dissimilar coping style differed in their level of optimization. If reactive females behaved optimally, any deviation from their original brood size should lower fitness, whereas this should not be the case for proactive females. Reactive females indeed performed best at their natural brood size, whereas proactive females performed best when raising an enlarged brood. These findings imply that proactive females produced sub-optimal brood sizes. We speculate that proactive females might (i) take decisions based on biased perception of their environment, (ii) face energetic constraints in offspring production and/or (iii) be more willing to invest into current reproduction when given the option. Our findings provide experimental evidence for coping style-related differences in optimal reproductive decisions and life-history strategies.
authors.affiliation: Evolutionary Ecology of Variation Research Group, Max Planck Institute for Ornithology, Eberhard-Gwinner-Straße 7, Seewiesen (Starnberg) 82319, Germany Department of Behavioural Ecology and Evolutionary Genetics, Max Planck Institute for Ornithology, Eberhard-Gwinner-Straße 7, Seewiesen (Starnberg) 82319, Germany mnicolaus@orn.mpg.de.
authors.forename: Marion
authors.initials: M
authors.lastname: Nicolaus
authors.affiliation: Evolutionary Ecology of Variation Research Group, Max Planck Institute for Ornithology, Eberhard-Gwinner-Straße 7, Seewiesen (Starnberg) 82319, Germany Department of Behavioural Ecology and Evolutionary Genetics, Max Planck Institute for Ornithology, Eberhard-Gwinner-Straße 7, Seewiesen (Starnberg) 82319, Germany.
authors.forename: Kimberley J
authors.initials: KJ
authors.lastname: Mathot
authors.affiliation: Evolutionary Ecology of Variation Research Group, Max Planck Institute for Ornithology, Eberhard-Gwinner-Straße 7, Seewiesen (Starnberg) 82319, Germany Department of Behavioural Ecology and Evolutionary Genetics, Max Planck Institute for Ornithology, Eberhard-Gwinner-Straße 7, Seewiesen (Starnberg) 82319, Germany.
authors.forename: Yimen G
authors.initials: YG
authors.lastname: Araya-Ajoy
authors.affiliation: Evolutionary Ecology of Variation Research Group, Max Planck Institute for Ornithology, Eberhard-Gwinner-Straße 7, Seewiesen (Starnberg) 82319, Germany Department of Behavioural Ecology and Evolutionary Genetics, Max Planck Institute for Ornithology, Eberhard-Gwinner-Straße 7, Seewiesen (Starnberg) 82319, Germany.
authors.forename: Ariane
authors.initials: A
authors.lastname: Mutzel
authors.affiliation: Evolutionary Ecology of Variation Research Group, Max Planck Institute for Ornithology, Eberhard-Gwinner-Straße 7, Seewiesen (Starnberg) 82319, Germany Department of Behavioural Ecology and Evolutionary Genetics, Max Planck Institute for Ornithology, Eberhard-Gwinner-Straße 7, Seewiesen (Starnberg) 82319, Germany.
authors.forename: Jan J
authors.initials: JJ
authors.lastname: Wijmenga
authors.affiliation: Department of Behavioural Ecology and Evolutionary Genetics, Max Planck Institute for Ornithology, Eberhard-Gwinner-Straße 7, Seewiesen (Starnberg) 82319, Germany.
authors.forename: Bart
authors.initials: B
authors.lastname: Kempenaers
authors.affiliation: Evolutionary Ecology of Variation Research Group, Max Planck Institute for Ornithology, Eberhard-Gwinner-Straße 7, Seewiesen (Starnberg) 82319, Germany Department of Behavioural Ecology and Evolutionary Genetics, Max Planck Institute for Ornithology, Eberhard-Gwinner-Straße 7, Seewiesen (Starnberg) 82319, Germany Behavioural Ecology, Department Biologie der LMU, Ludwig Maximilians University of Munich (LMU), Großhadener Straße. 2, Planegg-Martinsried 82152, Germany.
authors.forename: Niels J
authors.initials: NJ
authors.lastname: Dingemanse
mesh_terms: D000818:Animals; D001522:Behavior, Animal; D052284:Clutch Size; D003657:Decision Making; D005260:Female; D046109:Passeriformes / Q000502:physiology*; D012098:Reproduction
keywords: Parus major; animal personality; coping styles; individual optimization; information use; phenotypic plasticity