Environmental correlates and co-occurrence of three mitochondrial lineages of striped mice (Rhabdomys) in the Free State Province (South Africa)

This study shows how data emanating from very different sources can be integrated using modern statistical and spatially explicit techniques in order to gain insights into ecological processes leading to differentiation between closely related taxa. We test ecological radiation in the striped mouse (Rhabdomys sp.) using a niche modeling approach to compare habitat characteristics of its three mitochondrial lineages, which we show to co-occur in a South African province. Here, we describe and make predictions on the distribution and potential niches of these lineages and locate contact zones between them. Our study involved field investigations, genotyping, GIS and multivariate statistics analyses. We used Maxent, an approach allowing us to produce suitability maps and predict potential contact zones. Our results strongly suggest that the three lineages could have different environmental niches which may explain their co-occurrence in some areas. Further, these results might give credence to the hypothesis of ecological radiation within the genus, which could be further tested in contact zones highlighted in our study. (c) 2012 Elsevier Masson SAS. All rights reserved.