Female chronotype and aggression covary on different hierarchical levels in a songbird
Individual variation in the timing of activities is increasingly being reported for a wide variety of species, often measured as the timing of activity onset in the morning. However, so far, the adaptive significance of consistent variation in temporal phenotypes (i.e. the chronotype) remains largely elusive. Potentially, differences in timing of activities may arise as a result of competition among individuals for resources. Less aggressive individuals may try to avoid competition by becoming active earlier during the day when other individuals are still inactive, leading to a positive correlation between chronotype and aggressive personality type (i.e. a behavioural syndrome). To investigate this, we assessed the chronotype of female great tits, Parus major, by measuring emergence time from the nestbox in the morning and experimentally tested their levels of same-sex aggression through simulated territorial intrusion tests. Contradicting our initial hypothesis, consistently more aggressive females became active earlier during the day compared to less aggressive females, which could be caused by shared underlying mechanisms, like pleiotropic effects of sex hormones or gene pleiotropy, which potentially impose constraints on the independent evolution of both traits. Surprisingly, on the within-individual level we found an opposing correlation between emergence time and aggression. Our findings highlight the need for further investigations into the interplay between chronotype and aggression that take the underlying mechanisms into account in order to understand the adaptive significance of this trait association.
Source (journal)
Animal behaviour. - London
London : 2024
210 (2024) , p. 75-83
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The author-created version that incorporates referee comments and is the accepted for publication version Available from 19.08.2024
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Effects of light pollution on behavioural, life-history and physiological traits in a songbird: an integrative approach.
Integrative and experimental study of the effects of artificial light exposure at night during development in birds in the real world: merging mechanistic approaches with short- and long-term health and fitness consequences.
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Publications with a UAntwerp address
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Creation 18.03.2024
Last edited 20.03.2024
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