Species-level paraphyly inferred from mitochondrial gene trees is a prevalent phenomenon in taxonomy and systematics, but there are several potential causes that are not easily explained by currently used methods. The present study aims to test the underlying causes behind the observed paraphyly of Streak-breasted Scimitar Babbler (Pomatorhinus ruficollis) via statistical analyses of four mitochondrial (mtDNA) and nine nuclear (nuDNA) genes. Mitochondrial gene trees show paraphyly of P. ruficollis with respect to the Taiwan Scimitar...

Niche evolution underpins the generation and maintenance of biological diversity, but niche conservatism, in which niches remain little changed over time in closely related taxa and the role of ecology in niche evolution are continually debated. To test whether climate niches are conserved in two closely related passerines in East Asia – the vinous-throated (Paradoxornis webbianus) and ashy-throated (P. alphonsianus) parrotbills – we established their potential allopatric and sympatric regions using ecological niche models and...