Open AccessTriploidy in a sexually dimorphic passerine provides new evidence for the effect of the W chromosome on secondary sexual traits in birds
Author(s) -
Camargo Crisley,
Gibbs H. Lisle,
Costa Mariellen C.,
Silveira Luís F.,
Rainho Cláudia A.,
Ribolla Paulo E. M.,
Wasko Adriane P.,
Francisco Mercival R.
Publication year - 2017
Publication title -
journal of avian biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.022
H-Index - 76
eISSN - 1600-048X
pISSN - 0908-8857
DOI - 10.1111/jav.01504
Subject(s) - biology , passerine , plumage , sexual dimorphism , locus (genetics) , chromosome , genetics , x chromosome , dosage compensation , y chromosome , secondary sex characteristic , gene , zoology , evolutionary biology , hormone , biochemistry
In birds, there are two main models for the determination of sex: the ‘Z Dosage’ model in which the number, or dose, of Z chromosomes determines sex, and the ‘Dominant W’ model which argues that a specific gene in the W chromosome may influence Z gene expression and determine sex. The best evidence for W determination of sex comes from birds with 2 copies of the Z chromosome paired with a single W (e.g. ZZW) which are nonetheless females. Here, we expand the species where such a mechanism may operate by reporting a case of a triploid Neotropical passerine bird with sexually dimorphic plumage, the São Paulo marsh antwren Formicivora paludicola . Evidence from 17 autosomal unlinked microsatellite loci, and CHD1 sex‐linked locus, indicate that this individual is a 3n ZZW triploid with intermediate plumage pattern. This example expands our knowledge of sex determination mechanisms in birds by demonstrating that both the W and the two Z chromosomes affect the expression of morphological secondary sexual traits in a non‐galliform bird.