کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
5896445 1154840 2013 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Trends of karyotypical evolution in the pearl cichlid, Geophagus brasiliensis, from southern Brazil
موضوعات مرتبط
علوم زیستی و بیوفناوری علوم کشاورزی و بیولوژیک علوم دامی و جانورشناسی
پیش نمایش صفحه اول مقاله
Trends of karyotypical evolution in the pearl cichlid, Geophagus brasiliensis, from southern Brazil
چکیده انگلیسی
Chromosomal rearrangements such as inversions can facilitate speciation even in the presence of gene flow. The present study aims to analyze the karyotypic variation in six populations of Geophagus brasiliensis from southern Brazil. All specimens showed 2n = 48 chromosomes, but three karyotypes were found to have one, two or three pairs of submetacentric chromosomes. Although G. brasiliensis did not exhibit variation in the diploid number, it presented a wide interpopulational variation mainly regarding the karyotype formula and specific chromosomal markers. Differences in the location of the major and minor rDNA loci were observed among the populations. Moreover, different patterns were observed in the distribution of the constitutive heterochromatin, presenting intra- and interpopulational variation. This supports the hypothesis that this taxon represents a complex species or that cryptic species are included in this group, indicating a possibleprocess of sympatric speciation. By potentially restricting gene flow between heterokaryotypes, the segregating chromosome rearrangements we describe for G. brasiliensis may play a role in diversification in this species complex.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Zoology - Volume 116, Issue 5, October 2013, Pages 286-292
نویسندگان
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