Systematics
The Ground Tit was traditionally considered a relative of the ground jays (Podoces), based on its voice and habits. Its autapomorphies have certainly puzzled 20th century ornithologists, but due to its remote range and nondescript appearance, it was little studied and not suspected to be anything but an aberrant ground jay for more than 100 years after its description by Hume. In 1978 and 1989 however, two studies of its anatomy determined that – although at that time unassignable to any family due to its peculiar adaptations, it appeared that it was not a corvid but a more advanced songbird of the infraorder today known as Passerida.
From 2003 onwards, osteological, mtDNA and nDNA sequence and other biochemical data has firmly allied it with the tits and chickadees (Paridae). In fact, genetic evidence suggests that it is a closer relative of the Great Tit and its relatives in the genus Parus sensu stricto than the chickadees and their relatives of the genus Poecile.
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