Chemistry of the uropygial gland secretion of Hume’s ground jay Pseudopodoces humilis and its taxonomic implications

Abstract

Hume's ground jay (Pseudopodoces humilis), a species living in the high altitude steppes of the Qinghai- Tibet-Plateau (China), was traditionally thought to be a ground jay related to the genus Podoces (Corvidae). Recently, however, based on three independent datasets (comparative osteology, nuclear and mitochondrial DNA sequences), this species was discovered to be a member of the Paridae. Here, we reinvestigate the sys- tematic position of Pseudopodoces humilis using the chemical composition of uropygial gland secretions, which have previously been shown to be phylogeneti- cally informative in birds, including Corvidae and Paridae. We found strong similarities in the fatty acid composition of uropygial gland secretions between Pseudopodoces humilis and parids, but clear differences from corvids. This result supports the parid affinites of Pseudopodoces, but stands in contrast to behavioural and vocal characteristics which are clearly more similar to corvids than to parids.