Intraspecific genetic lineages of a marine mussel show behavioural divergence and spatial segregation over a tropical/subtropical biogeographic transition

BMC Evolutionary Biology

Research Article

Katy R Nicastro¹  Rita Castilho¹  Ester A Serrão¹  Gareth A Pearson¹  Joana Costa²  Gerardo I Zardi³  Christopher D McQuaid³ 

[1] Centre of Marine Sciences – CCMAR, Campus de Gambelas, Universidade do Algarve, 8005-139, Faro, Portugal;Centre of Marine Sciences – CCMAR, Campus de Gambelas, Universidade do Algarve, 8005-139, Faro, Portugal;Present address: Algal Biology Lab, School of Botany, The University of Melbourne, 3010, Parkville, VIC, Australia;Department of Zoology and Entomology, Rhodes University, 6140, Grahamstown, South Africa;

关键词: Genetic diversity;    Marine connectivity;    Perna perna;   

DOI  :  10.1186/s12862-015-0366-5

 received in 2014-12-17, accepted in 2015-04-29,  发布年份 2015

来源: Springer

【 摘 要 】

BackgroundIntraspecific variability is seen as a central component of biodiversity. We investigated genetic differentiation, contemporary patterns of demographic connectivity and intraspecific variation of adaptive behavioural traits in two lineages of an intertidal mussel (Perna perna) across a tropical/subtropical biogeographic transition.ResultsMicrosatellite analyses revealed clear genetic differentiation between western (temperate) and eastern (subtropical/tropical) populations, confirming divergence previously detected with mitochondrial (COI) and nuclear (ITS) markers.Gene flow between regions was predominantly east-to-west and was only moderate, with higher heterozygote deficiency where the two lineages co-occur. This can be explained by differential selection and/or oceanographic dynamics acting as a barrier to larval dispersal.Common garden experiments showed that gaping (periodic closure and opening of the shell) and attachment to the substratum differed significantly between the two lineages. Western individuals gaped more and attached less strongly to the substratum than eastern ones.ConclusionsThese behavioural differences are consistent with the geographic and intertidal distributions of each lineage along sharp environmental clines, indicating their strong adaptive significance. We highlight the functional role of diversity below the species level in evolutionary trends and the need to understand this when predicting biodiversity responses to environmental change.

【 授权许可】

Unknown   
© Zardi et al.; licensee BioMed Central. 2015. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.