5. Conclusions
Our study used combined characteristics from morphological analysis and
multilocus approaches to show that the Naumann’s and dusky thrush
complexes and the red-throated and black-throated thrush complexes in
the Turdidae family should be divided into two separate species
(T. naumanni and T. ruficollis ) and two subspecies.
Importantly, we validated extensive nuclear introgression betweenT. naumanni and T. ruficollis for the first time. We also
provided a potential explanation of the mechanism of gene introgression
and nuclear-mitochondrial discordance between the two birds. However, a
more-comprehensive collection of specimens of these birds in their
breeding range is needed to clarify the relationship between gene
introgression and speciation in these birds.