Open AccessGenetic variability in geographic populations of the natterjack toad ( B ufo calamita )
Author(s) -
Oromi N.,
RichterBoix A.,
Sanuy D.,
Fibla J.
Publication year - 2012
Publication title -
ecology and evolution
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.17
H-Index - 63
ISSN - 2045-7758
DOI - 10.1002/ece3.323
Subject(s) - bufo , genetic diversity , biological dispersal , ecology , biology , range (aeronautics) , pleistocene , genetic variation , genetic variability , geographical distance , genetic structure , toad , population , paleontology , demography , genetics , materials science , sociology , gene , genotype , composite material
Across altitudinal and latitudinal gradients, the proportion of suitable habitats varies, influencing the individual dispersal that ultimately can produce differentiation among populations. The natterjack toad ( B ufo calamita) is distributed across a wide geographic range that qualifies the species as interesting for a geographic analysis of its genetic variability. Five populations of B . calamita in the S ierra de G redos ( S pain) were studied in an altitudinal gradient ranging from 750 to 2270 m using microsatellite markers. In addition, we analyzed the latitudinal genetic variation in B . calamita within a global E uropean distribution using genetic diversity parameters (mean number of alleles per locus [ M a ] and expected heterozygosity [ H E ]) obtained from our results and those published in the literature. The low level of genetic differentiation found between populations of B . calamita ( F st ranging from 0.0115 to 0.1018) and the decreases in genetic diversity with altitude ( M a from 13.6 to 8.3, H E from 0.82 to 0.74) can be interpreted by the combined effects of discontinuous habitat, produced mainly by the high slopes barriers and geographic distance. In the latitudinal gradient, genetic diversity decreases from south to north as a consequence of the colonization of the species from the P leistocene refugium. We conclude that the genetic variability in B . calamita along its wide altitudinal and latitudinal geographic distribution mainly reflects the colonization history of the species after the last glacial period.