A Phylogenetic Perspective on The Phytogeography of Western Ghats

Abstract

I used a finer scale data of 156 published plots across the entire latitudinal range of WG, covering most of the protected forests. The pruned phylogeny for this study consisted of 367 species, of which ~ 50% are taxa endemic to WG. I first tested the southern refuge hypothesis by analysing the PE of all 367 species. my results show that plots significant for PE were more in the southern latitudes, indicating the presence of range restricted clades predominantly in the southern WG. I then partitioned the data to explore the contribution of endemics and non-endemics to the overall PE pattern. Both sets of species contribute fairly evenly to overall PE, indicating that although some species may not be endemic to WG, they have a restricted distribution within WG and belong to whole clades that are narrowly distributed across WG. These significant plots showed greater PE than expected for the number of range-restricted species present in those plots. Hence, this additional information can greatly aid in complementing the existing methods of assessing conservation prioritisation. In conclusion, this study shows the potential use of a community phylogenetics approach toward understanding the diversity of these communities. With the increasing ease of generating phylogenies and the growing species occurrence data, it is now possible to undertake such analyses across different taxonomic groups. Elucidating biogeographic history and conservation value are a few of its potential applications. My results, thus, lay the groundwork for further studies, such as assessing community assembly mechanisms, and understanding nice evolution of the flora of Western Ghats