Two new genera of songbirds represent endemic radiations from the Shola Sky Islands of the Western Ghats, India

BMC Evolutionary Biology

Research Article

Frank E. Rheindt¹  Daniel M. Hooper²  C. K. Vishnudas³  Uma Ramakrishnan³  Pooja Gupta³  Sushma Reddy⁴  V.V. Robin⁵ 

[1] Avian Evolution Lab, Department of Biological Sciences, Faculty of Science, National University of Singapore, 117543, Singapore, Singapore;Committee on Evolutionary Biology, University of Chicago, 60637, Chicago, IL, USA;National Centre for Biological Sciences, TIFR, Bellary Road, 560065, Bangalore, India;National Centre for Biological Sciences, TIFR, Bellary Road, 560065, Bangalore, India;Biology Department, Loyola University Chicago, 60660, Chicago, IL, USA;National Centre for Biological Sciences, TIFR, Bellary Road, 560065, Bangalore, India;Present address – Indian Institute of Science Education and Research Tirupati, 517507, Tirupati, Mangalam, India;

关键词: Phylogenetics;    Birds;    Shola;    Passerine;    Montane;    Sky-islands;    Taxonomy;    Tropics;   

DOI  :  10.1186/s12862-017-0882-6

 received in 2016-10-25, accepted in 2017-01-11,  发布年份 2017

来源: Springer

【 摘 要 】

BackgroundA long-standing view of Indian biodiversity is that while rich in species, there are few endemics or in-situ radiations within the subcontinent. One exception is the Western Ghats biodiversity hotspot, an isolated mountain range with many endemic species. Understanding the origins of the montane-restricted species is crucial to illuminate both taxonomic and environmental history.ResultsWith evidence from genetic, morphometric, song, and plumage data, we show that two songbird lineages endemic to the Western Ghats montane forest each have diversified into multiple distinct species. Historically labeled as single species of widespread Asian genera, these two lineages are highly divergent and do not group with the taxa in which they were previously classified but rather are distinct early divergences in larger Asian clades of flycatchers and babblers. Here we designated two new genera, the Western Ghats shortwings as Sholicola and the laughingthrushes as Montecincla, and evaluated species-limits to reflect distinct units by revising six previously named taxa and describing one novel species. Divergence dating showed that both these montane groups split from their Himalayan relatives during the Miocene, which is coincident with a shift towards arid conditions that fragmented the previously contiguous humid forest across peninsular India and isolated these lineages in the Western Ghats. Furthermore, these two genera showed congruent patterns of diversification across the Western Ghats Sky Islands, coincident with other climatic changes.ConclusionOur study reveals the existence of two independent endemic radiations in the high montane Western Ghats or Shola Sky Islands with coincident divergence times, highlighting the role of climate in the diversification of these ancient lineages. The endemic and highly divergent nature of these previously unrecognized species underscores the dearth of knowledge about the biogeography of the Asian tropics, even for comparatively well-known groups such as birds. The substantial increase in the diversity of this region underscores the need for more rigorous systematic analysis to inform biodiversity studies and conservation efforts.

【 授权许可】

CC BY   
© The Author(s). 2017