The authors Niclas Backström and Eleftheria Palkopoulou contributed equally to the study.
No evidence for Z-chromosome rearrangements between the pied flycatcher and the collared flycatcher as judged by gene-based comparative genetic maps
Article first published online: 28 JUL 2010
© 2010 Blackwell Publishing Ltd
Volume 19, Issue 16, pages 3394–3405, August 2010
How to Cite
BACKSTRÖM, N., PALKOPOULOU, E., QVARNSTRÖM, A. and ELLEGREN, H. (2010), No evidence for Z-chromosome rearrangements between the pied flycatcher and the collared flycatcher as judged by gene-based comparative genetic maps. Molecular Ecology, 19: 3394–3405. doi: 10.1111/j.1365-294X.2010.04742.x
- Issue published online: 5 AUG 2010
- Article first published online: 28 JUL 2010
- Received 11 February 2010; revision received 16 April 2010; accepted 27 April 2010
- chromosomal speciation;
- linkage mapping;
- sex chromosomes
Revealing the genetic basis of reproductive isolation is fundamental for understanding the speciation process. Chromosome speciation models propose a role for chromosomal rearrangements in promoting the build up of reproductive isolation between diverging populations and empirical data from several animal and plant taxa support these models. The pied flycatcher and the collared flycatcher are two closely related species that probably evolved reproductive isolation during geographical separation in Pleistocene glaciation refugia. Despite the short divergence time and current hybridization, these two species demonstrate a high degree of intrinsic post-zygotic isolation and previous studies have shown that traits involved in mate choice and hybrid viability map to the Z-chromosome. Could rearrangements of the Z-chromosome between the species explain their reproductive isolation? We developed high coverage Z-chromosome linkage maps for both species, using gene-based markers and large-scale SNP genotyping. Best order maps contained 57–62 gene markers with an estimated average density of one every 1–1.5 Mb. We estimated the recombination rates in flycatcher Z-chromosomes to 1.1–1.3 cM/Mb. A comparison of the maps of the two species revealed extensive co-linearity with no strong evidence for chromosomal rearrangements. This study does therefore not provide support the idea that sex chromosome rearrangements have caused the relatively strong post-zygotic reproductive isolation between these two Ficedula species.