Delineating fine-scale genetic units in amphibians:
probing the primacy of ponds

Jehle, R; Burke, T; Arntzen, JW

Abstract

The population structure of pond-breeding amphibians is shaped by their distinct breeding foci, but it is
unclear to what extent this is reflected in the fine-scale distribution of genetic diversity. We used microsatellite
genotypes to investigate the genetic signatures of 24 populations of European newts, Triturus
cristatus and T. marmoratus, inhabiting 21 ponds in a confined study area (7.5 · 3.5 km) in western France.
Employing a Bayesian clustering approach based on individual genotypes that minimises departures from
Hardy–Weinberg equilibrium and linkage disequilibrium, no evidence was found for within-pond substructuring.
Subjecting all sampled ponds simultaneously to this procedure revealed a clear signal of
partitioning, with the most likely number of clusters however below the actual number of ponds (seven in T.
cristatus, three in T. marmoratus). A more hierarchical Bayesian approach, with pond as analysis unit, was
achieved to separate ponds from genetically more meaningful units, and reduced the T. cristatus populations
to 11 clusters, and the T. marmoratus populations to five clusters. We were unable to specify a
minimum nearest-neighbour distance where ponds are separate units, probably due to both historical and
current demographic processes. The implications for strategies to manage and conserve endangered
amphibians in human-altered landscapes are discussed.

Citation

probing the primacy of ponds. Conservation Genetics, 6, 227-234. https://doi.org/10.1007/s10592-004-7832-8

• Journal Article Type: Article
• Publication Date: Jan 1, 2005
• Deposit Date: Oct 30, 2009
• Journal: Conservation Genetics
• Print ISSN: 1566-0621
• Publisher: Springer Verlag
• Peer Reviewed: Peer Reviewed
• Volume: 6
• Pages: 227-234
• DOI: https://doi.org/10.1007/s10592-004-7832-8
• Keywords: clustering methods, genetic units, microsatellites, newts, Triturus
• Publisher URL: http://dx.doi.org/10.1007/s10592-004-7832-8