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Candidate gene polymorphisms for behavioural adaptations during urbanization in blackbirds
J C Mueller1, J Partecke, B J Hatchwell
1Department of Behavioural Ecology & Evolutionary Genetics, Max Planck Institute for Ornithology, Seewiesen, Germany. mueller@orn.mpg.de
Molecular Ecology
|March 19, 2013
Summary
Blackbirds adapting to cities show genetic differences linked to harm avoidance behavior. This suggests consistent adaptive processes drive urbanization in Turdus merula populations.
Area of Science:
- Evolutionary biology
- Behavioral genetics
- Urban ecology
Background:
- Urban colonization presents novel environments for species adaptation.
- Behavioral traits are crucial for successful adaptation to new habitats.
Purpose of the Study:
- Investigate genetic basis of adaptation in urbanizing blackbirds (Turdus merula).
- Identify candidate genes associated with behavioral traits relevant to urbanization.
Main Methods:
- Genotyped 16 polymorphisms in candidate genes (circadian rhythms, harm avoidance, migratory/exploratory behavior).
- Compared urban and rural blackbird populations (12 pairs) across the Western Palaearctic.
- Analyzed genetic divergence at specific gene loci in relation to habitat type.
Main Results:
- A SERT gene microsatellite polymorphism showed significant association with habitat type (urban vs. rural).
- Genetic divergence at the SERT locus was consistent across most population pairs, unlike random markers.
- Harm avoidance behavior, linked to SERT, appears under selection during blackbird urbanization.
Conclusions:
- Harm avoidance behavior and SERT gene polymorphism are key factors in blackbird adaptation to urban environments.
- Urbanization events are influenced by consistent adaptive processes, not solely founder effects.
- This study highlights homogeneous adaptive processes in species adapting to novel urban settings.
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