Contrasting patterns of phylogenetic diversity across climatic zones of Western Ghats: A biodiversity hotspot in peninsular India

Divya, B and Ramesh, BR and Karanth, KP (2020) Contrasting patterns of phylogenetic diversity across climatic zones of Western Ghats: A biodiversity hotspot in peninsular India. In: Journal of Systematics and Evolution .

	PDF jou_sys_evo_2020.pdf - Published Version Restricted to Registered users only Download (718kB) | Request a copy
	Microsoft Word jse12663-sup-0001-ifp_supplementary_jse_1_0.doc - Published Supplemental Material Restricted to Registered users only Download (249kB) | Request a copy

Abstract

This study attempts to understand the biogeographic history of the Western Ghats forests by investigating decoupling between phylogenetic and taxonomic diversity. We specifically test whether the deciduous forests have been recently established, whether the southern region was a refuge, and whether the deciduous and evergreen forest species have disparate evolutionary histories. We used species composition data from 23 forest types along the Western Ghats for all woody angiosperms above 10-cm diameter at breast height. Forests were broadly grouped as either evergreen or deciduous. Mean phylogenetic distances corrected for species richness and mean phylogenetic beta diversity corrected for shared species were assessed using z-scores from null distributions. Null distributions were generated by randomizing the species relationships on the phylogeny. We found that all evergreen forests showed a greater phylogenetic diversity as compared with null expectations. Deciduous forests showed the inverse pattern. Within the evergreen belt, there was a decreasing phylogenetic diversity from south to north, as predicted by the southern refuge hypothesis. The phylogenetic beta diversity across evergreen�deciduous forests was lesser than the null expectation, whereas it was much higher across forests within the evergreen belt. This study provides the first phylogenetic evidence for the antiquity of evergreen forests as well as the southern refuge hypothesis in the Western Ghats. The deciduous forests species have shared evolutionary histories with the evergreen forest species, suggesting multiple shifts between evergreen and deciduous states through the lineages. Conversely, the evergreen species exhibited a disparate evolutionary history across these forests, possibly owing to sharper ecological or climatic gradients. © 2020 Institute of Botany, Chinese Academy of Sciences

Item Type:	Journal Article
Publication:	Journal of Systematics and Evolution
Publisher:	Wiley-Liss Inc.
Additional Information:	The copyright of this article belongs to Wiley-Liss Inc.
Department/Centre:	Division of Biological Sciences > Centre for Ecological Sciences
Date Deposited:	02 Nov 2020 06:23
Last Modified:	02 Nov 2020 06:23
URI:	http://eprints.iisc.ac.in/id/eprint/66503

Actions (login required)

View Item