Studying speciation in birds

Despite huge advances in genomic sequencing and other molecular tools, scientists still lack a technical understanding of how speciation occurs in animals. In particular, it would be valuable to understand the genetic mechanisms that result in speciation.

The EU-funded 'Speciation genomics in a wild bird populations' (SPECIATIONGENOMICS) project studied interbreeding between the collared flycatcher (Ficedula albicollis) and the pied flycatcher (Ficedula hypolecua). Flycatchers are good study species as they happily breed in box nests and usually stay in one breeding site for long periods.

Researchers collected data about breeding, physical appearance and behaviour in these birds over a long period. They compared this data to genetic changes either on the sex-linked chromosome (called the Z chromosome in birds) or elsewhere in the birds' genomes.

Generally, researchers found that changes on the Z chromosome were minor in comparison to non-sex-linked variation. One exception was noted: wing patches in collared flycatchers varied widely and were associated with changes on the Z chromosome.

Lastly, SPECIATIONGENOMICS used a molecular biology technique to identify areas of the genome that influence physical traits. The recently sequenced genome of the collared flycatcher and the physiological data collected previously allowed researchers to search for genes associated with speciation.

The work done during SPECIATIONGENOMICS has advanced our understanding of the mechanics driving speciation. This will contribute to scientists' grasp of evolution, and may lead to improved conservation efforts.