Conservation implications and conclusions
Although the Nanling Range has long been recognized as a biodiversity and conservation hotspot (Spehn et al. 2010, Nieto Feliner 2014, Mi et al. 2021), most studies of the biogeographic and environmental importance of the Range have focused on its relictual plants, such as the endemic South China Five-needle Pine Pinus armandii (Tian et al. 2010) and the monotypic, tertiary, relictual tree Eurycorymbus cavaleriei (Wang et al. 2009), and the role of the mountains as a corridor for such plants (Tian et al. 2018). With respect to animals, studies are fewer, but initial work suggests there is little overlap between faunal and floral hotspots in the mountains (Xu et al. 2018). Nevertheless, ENM in this study indicates a likely relationship between plant and bird occurrence in the mountains over recent geologic history, from 21000 years to present (Supporting information). The mountains maintained appropriate habitat for the 5 target species at its eastern end during the LGM and then, with global warming, that habitat and its birds spread westward. Thus, the mountains provided a refuge during the harshest climate change and a conduit during more ameliorated times. The mountains also serve as a north-south boundary and watershed, separating open wetlands to the north from more subtropical forest habitat to the south.