Multilocus characterization of a woodrat (genus Neotoma) hybrid zone

In order to investigate hybridization between 2 species of woodrats, Neotoma floridana and Neotoma micropus, 103 specimens were collected, in March of 1988, from a known area of sympatry, and compared with reference collections from areas of allopatry. Ten genetic markers, consisting of 7 microsatellite loci, 1 mitochondrial gene (cytochrome-b [Cytb]), and 2 nuclear introns (intron 2 of the vertebrate alcohol dehydrogenase gene [Adh1-I2] and intron 7 of the beta-fibrinogen gene [Fgb-I7]) were used to develop a composite genotype for each individual and for detection of hybridization. Six individuals were identified as pure parental N. micropus, 96 as hybrids, and 1 as pure parental N. floridana. Hybrids were formed primarily through matings between complex genotypes, resulting in a high prevalence of individuals classified as backcrosses. The ratio of hybrid classes, population substructure, and presence of significant linkage disequilibrium within the zone of contact could not reject e...为探究佛罗里达林鼠（Neotoma floridana）与小耳林鼠（Neotoma micropus）两个物种间的杂交现象，研究人员于1988年3月在一处已知的同域分布区域采集了103份标本，并与来自异域分布区域的参考馆藏标本进行比对。本研究采用10个遗传标记构建每个个体的复合基因型以检测杂交事件，其中包含7个微卫星位点（microsatellite loci）、1个线粒体基因（mitochondrial gene）——细胞色素b（cytochrome-b, Cytb），以及2个核内含子：脊椎动物乙醇脱氢酶基因第2内含子（intron 2 of the vertebrate alcohol dehydrogenase gene, Adh1-I2）与β-纤维蛋白原基因第7内含子（intron 7 of the beta-fibrinogen gene, Fgb-I7）。经鉴定，6份标本为纯合的亲本小耳林鼠，96份为杂交个体，仅1份为纯合的亲本佛罗里达林鼠。杂交个体主要由具有复杂基因型的个体交配产生，回交（backcrosses）个体占比极高。杂交类群比例、种群亚结构以及接触带内显著的连锁不平衡（linkage disequilibrium）现象均无法排除……