Abstract:
:Morphological and genetic characters from cyprinid fishes of the genus Gila were examined to assess a hypothesized hybrid origin of Gila seminuda from the Virgin River, Arizona-Nevada-Utah. The presumed parents, Gila robusta robusta and Gila elegans, are clearly differentiated from one another based on morphology, allozymes, and mtDNA haplotypes. G. seminuda is morphologically intermediate and polymorphic at allozyme loci diagnostic for the parental species. Restriction endonuclease analysis of mtDNA showed G. seminuda nearly identical to G. elegans. These results support an origin of the bisexual taxon G. seminuda through introgressive hybridization. The Gila population in the Moapa River, Nevada, also appears to be of hybrid origin and is considered a distinctive population of G. seminuda. Inter-specific hybridization is potentially an important mode of evolution among western North American fishes, and valid species of hybrid origin may exist in other groups as well. Consideration of this mode of evolution argues for the need to conserve entire species complexes.
journal_name
Proc Natl Acad Sci U S Aauthors
DeMarais BD,Dowling TE,Douglas ME,Minckley WL,Marsh PCdoi
10.1073/pnas.89.7.2747keywords:
subject
Has Abstractpub_date
1992-04-01 00:00:00pages
2747-51issue
7eissn
0027-8424issn
1091-6490journal_volume
89pub_type
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