Genetics of migratory traits in a long-distance migrant
The great reed warbler is a long-distance migrant breeding in Europe and wintering in sub-Saharan Africa. Our team has studied the species at a Swedish breeding site for the last 29 years. We have shown that wing length – a crucial trait for long-distance migrants – is highly heritable and differs between populations; long-winged birds in north and short-winged in south. Moreover, we have used QTL analysis to find genes underlying variation in wing length. Interestingly, this analysis located one or more genes coding for wing length to a region at chromosome 2 (a so called QTL site). Interestingly, this chromosome region has recently been identified as important for wing length also in zebra finch, suggesting that its wing length determining function is general among birds.
In this project, we aim to increase the mapping resolution drastically by using a newly developed molecular method (RAD-tag sequencing) on a carefully selected subset of our mapping pedigree. In a small pilot project we found that c. 70,000 markers will be screened simultaneously with this technique. This will revolutionize our ability to fine-map wing morphology, dissect the genetic architecture of a migratory trait and address the evolutionary dynamics of migration on a genetic level.