z-logo
open-access-imgOpen Access
Increased divergence but reduced variation on the Z chromosome relative to autosomes in Ficedula flycatchers: differential introgression or the faster‐Z effect?
Author(s) -
Hogner Silje,
Sæther Stein A.,
Borge Thomas,
Bruvik Torbjørn,
Johnsen Arild,
Sætre GlennPeter
Publication year - 2012
Publication title -
ecology and evolution
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.17
H-Index - 63
ISSN - 2045-7758
DOI - 10.1002/ece3.92
Subject(s) - autosome , biology , genetics , introgression , gene flow , x chromosome , chromosome , evolutionary biology , genetic variation , gene
Recent multilocus studies of congeneric birds have shown a pattern of elevated interspecific divergence on the Z chromosome compared to the autosomes. In contrast, intraspecifically, birds exhibit less polymorphism on the Z chromosome relative to the autosomes. We show that the four black‐and‐white Ficedula flycatcher species show greater genetic divergence on the Z chromosome than on the autosomes, and that the ratios of intraspecific polymorphism at Z‐linked versus autosomal markers are below the neutral expectation of 75%. In all species pairs, we found more fixed substitutions and fewer shared polymorphisms on the Z chromosome than on the autosomes. Finally, using isolation with migration (IMa) models we estimated gene flow among the four closely related flycatcher species. The results suggest that different pattern of evolution of Z chromosomes and autosomes is best explained by the faster‐Z hypothesis, since the estimated long‐term gene flow parameters were close to zero in all comparisons.

The content you want is available to Zendy users.

Already have an account? Click here to sign in.
Having issues? You can contact us here