Open AccessMultilocus analyses indicate a mosaic distribution of hybrid populations in ground squirrels (genus Ictidomys )
Author(s) -
Thompson Cody W.,
Anwarali Khan Faisal Ali,
Stangl Frederick B.,
Baker Robert J.,
Bradley Robert D.
Publication year - 2013
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/ece3.755
Subject(s) - biology , gene flow , amplified fragment length polymorphism , biological dispersal , population , evolutionary biology , genetics , mitochondrial dna , gene , zoology , genetic variation , genetic diversity , demography , sociology
DNA sequence data from mitochondrial cytochrome‐ b ( Cyt b) and Y‐linked structural maintenance of chromosomes ( SmcY ) genes were combined with 478 nuclear loci obtained from amplified fragment length polymorphisms ( AFLP ) to assess the extent of hybridization and genetic spatial structure of populations in two hybridizing species of ground squirrel ( Ictidomys parvidens and Ictidomys tridecemlineatus ). Based on AFLP analyses of 134 individuals from 28 populations, 10 populations were identified that possessed hybrid individuals. Overall estimates of F ST values revealed strong support for population structure in the Cyt b data set; however, analyses of the SmcY gene and the AFLP data indicated ongoing gene flow between species. Pairwise F ST comparisons of populations were not significant for the SmcY gene; although they were significant for the Cyt b gene, indicating that these populations were structured and that gene flow was minimal. Therefore, gene flow between I. parvidens and I. tridecemlineatus appeared to be restricted to populations that exhibited hybridization. In addition, the fragmented nature of the geographic landscape suggested limited gene flow between populations. As a result, the distributional pattern of interspersed parental and hybrid populations were compatible with a mosaic hybrid zone model. Because ground squirrels display female philopatry and male‐biased dispersal, the ecology of these species is compatible with this hypothesis.