Consulta: subjectFacets:"Clinal variation"
Registros recuperados: 2
Data/hora: 10/06/2024 01:33:25

Karyological geographic variation of Oligoryzomys nigripes Olfers, 1818 (Rodentia, Cricetidae) from Brazil
Provedor de dados: 74
Autores: Paresque,Roberta; Silva,Maria José de Jesus; Yonenaga-Yassuda,Yatiyo; Fagundes,Valéria.
The karyotypes of 85 specimens of Oligoryzomys nigripes (Rodentia, Sigmodontinae) collected in the Cerrado and Atlantic Forest of seven states of Brazil were analyzed. Eighty four specimens presented a karyotype with 2n = 62 and one individual had 2n = 61 due to a monosomy of the X chromosome. High levels of intra- and inter-population karyotypic variability, due to sex chromosomes heteromorphisms and pericentric inversions in four autosomes (pairs 2, 3, 4 and 8), led to a variation of the autosomal arm numbers (fundamental number, FN) from 78 to 82. Synaptonemal complex analyses revealed normal meiosis in males heterozygous for pericentric inversions. We found 39 different cytotypes, 27 of which are herein described for the first time. A literature survey...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Pericentric inversion; Oryzomyini; Oligoryzomys nigripes; Rodentia; Clinal variation.
Ano: 2007
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572007000100010

Morphological variation in two genetically distinct groups of the golden-striped salamander, Chioglossa lusitanica (Amphibia: Urodela)
Provedor de dados: 16
Autores: Alexandrino, J.; Ferrand, N.; Arntzen, J.W.
Morphometric and colour pattern variation in the endemic Iberian salamander Chioglossa lusitanica is concordant with the genetic differentiation of two groups of populations separated by the Mondego river in Portugal. Salamanders from the south have shorter digits than those from the north. Clinal variation with a south to north increase in limb, toe and finger length was found superimposed on this dichotomy, resulting in stepped clines for characters describing appendage size. Genetic variability was paralleled by colour pattern variability in the contact zone and in northern populations. To explain the observed parallels we invoke the neutral processes of vicariant isolation, admixture in a secondary contact zone, genetic drift in addition to selection...
Tipo: Article / Letter to the editor
Palavras-chave: Amphibia; Chioglossa lusitanica; Clinal variation; Colour pattern; Golden-striped salamander; Morphometrics; 42.82.
Ano: 2005
URL: http://www.repository.naturalis.nl/record/209648