Data/hora: 09/06/2024 17:17:29

Provedor de dados: | 54
País: | Brazil
Título: | Estimated frequency of B-chromosomes and population density of Astyanax scabripinnis paranae in a small stream
Autores: | Porto-Foresti,Fábio; Oliveira,Claudio; Maistro,Edson Luis; Foresti,Fausto.
Data: | 1997-09-01
Ano: | 1997
Resumo: | A study was made of the frequency of B-chromosomes and the population density of Astyanax scabripinnis paranae (Pisces, Characidae, Tetragonopterinae) from three stretches of the Cascatinha stream (Botucatu, SP). In the first stretch the population was estimated to be about 212 individuals and among 35 karyotyped specimens, 23 carried one macro B-chromosome; in the second stretch the population was estimated to be about 650 individuals and among 20 specimens karyotyped, two possessed one macro B-chromosome; in the third stretch the population was estimated to be about 107 individuals and among 10 specimens karyotyped, one carried one macro B-chromosome. A significant difference was observed in the frequency of macro B-chromosomes in females (57%) and males (8.7%) (P = 0.0001). These data suggest that the B-chromosome frequency and the populational density are not directly related. The hypothesis of the existence of some adaptive effect conferred by the B-chromosomes to the specimens from the first stretch of the Cascatinha stream is presented and discussed
Tipo: | Info:eu-repo/semantics/article
Idioma: | Inglês
Identificador: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-84551997000300004
Editor: | Sociedade Brasileira de Genética
Relação: | 10.1590/S0100-84551997000300004
Formato: | text/html
Fonte: | Brazilian Journal of Genetics  v.20 n.3 1997
Fonte: | info:eu-repo/semantics/openAccess