Patterns of contact call differentiation in the panmictic East African Abyssinian White‐eye Zosterops abyssinicus (Aves: Passeriformes)

Ecology and Evolution

Jan Christian Habel²  Martin Husemann¹ 

[1] General Zoology, Institute of Biology, Martin-Luther University Halle-Wittenberg, Halle (Saale), Germany;Terrestrial Ecology Research Group, Department of Ecology and Ecosystem Management, School of Life Sciences Weihenstephan, Technische Universität München, Freising, Germany

关键词: Acoustic communication;    allopatry;    character displacement;    contact calls;    geographic gradients;    sonogram;    sympatry;   

DOI  :  10.1002/ece3.1828

来源: Wiley

【 摘 要 】

Abstract

Species distribution patterns range from highly disjunct to continuous, depending on their ecological demands and the availability of respective habitats. East African savannahs are mostly interconnected and ecologically comparatively homogenous and thus provide a prerequisite for a rather panmictic distribution pattern for species occurring in this habitat. The Abyssinian white-eye Zosterops abyssinicus is a savannah inhabiting bird species, representing such a continuous distribution. This species occurs in high abundances and is very mobile, and past population genetic studies have suggested that gene flow is high and genetic differentiation is low even across relatively large geographic distances. Further, only little morphological differences were found. In order to test for potential divergence in acoustic traits despite its interconnected geographic distribution, we analyzed 2795 contact calls of Z. abyssinicus, which were recorded at 19 sites across Kenya. Our data indicate weak, but significant differentiation in call characteristics across latitudinal gradients. We found strong changes in call characteristics in populations where Z. abyssinicus occurs in sympatry with its highland congener, Zosterops poliogaster. However, the changes in call characteristics in sympatry were in different directions and lead to strong differentiation of the sympatric populations to other conspecific populations potentially representing a case of cascade reinforcement. The detected spatial gradients likely result from ecological differences and balancing effects of natural and sexual selection.

【 授权许可】

CC BY   
© 2015 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.

Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.