The subspecies formosanus, distributed in Taiwan, was described by
Ernst Hartert in 1910. It is now proposed to be a full species, the
Taiwan bush robin (T. formosanus), in a
molecular phylogenetic study published in 2022. It is distinctive in
genetics,
songs and
morphology.[4] In 2024, the IOC World Bird List formally split the Taiwan Bush Robin from the White-Browed Bush Robin[5]
White-browed bush robins display delayed
plumage maturation—after
becoming capable of breeding, first-year males (subadults) retain their juvenile plumage (similar to that of adult females) to avoid direct competition with older males.[6]
^Neupane, Juna, Laxman Khanal, and Mukesh Kumar Chalise. "Avian diversity in Kaligandaki River basin, Annapurna conservation area, Nepal." International Journal of Ecology and Environmental Sciences 46.2 (2020): 99-110.