Postdoctoral Research
Fulbright Postdoctoral Fellow, University of Maryland Under the Fulbright-Nehru Postdoctoral Program in the Espindola lab, my work focuses on the effect of biotic (pollinators) and abiotic environment changes on the evolutionary history of mountain endemic plant-pollinator interactions. I use rhododendrons as my model system to approach this central question in evolution and conservation. I incorporate ecological, geospatial data and phylogeny with modern analytical tools to generate scientific knowledge in the ecology and evolution of rhododendrons and improve endemic mountain plants' conservation efforts worldwide. Funding: United States-India Educational Foundation, Azalea Society of America, Maryland Native Plant Society |
Postdoctoral Associate
Ashoka Trust for Research in Ecology and Environment The Indian Himalaya Rhododendron is one of the largest flowering plant genera. They are also a livelihood source for many rural Himalayan communities. However, climate change and the ever‐increasing demand for natural resources have negatively impacted Indian Himalayan rhododendrons in their natural habitats. In addition, available data on various aspects of taxonomy, ecology, and conservation status are scanty. Therefore, after completing my Ph.D. I continued working as a Postdoctoral Associate in ATREE for seven months and compiled a critical review on the taxonomy, evolutionary history, economic importance, and conservation status of rhododendrons in the Indian Himalaya. Further, I discuss the strategies to be adopted for the conservation of Rhododendron-dominated forests in the Indian Himalaya. Full article Funding: American Rhododendron Society, Department of Biotechnology, Government of India |
Ph.D. Research
Phenolology of Himalayan Rhododendrons: Influence of abiotic factors, pollinators and phylogeny My Ph.D. study illustrates a complex interplay of abiotic, pollinators, and evolutionary history in determining the reproductive phenology of 10 locally aggregated high‐elevation Rhododendron species in Kyongnosla Alpine Sanctuary, Sikkim Himalaya. The fieldwork was carried out between 2013 and 2015 across an elevation gradient of 3400 to 4230m. Funding: Department of Biotechnology, Government of India and National Mission on Himalayan Studies 1. Influence of phylogeny and abiotic factors varies across early and late reproductive phenology The study demonstrates how the influence of abiotic factors and phylogenetic conservatism vary across different reproductive phenology events. A strong phylogenetic signal was observed across species for the early phenology events such as budding, flowering, and initial fruiting. However, the role of abiotic factors was more important for the later phenology events such as immature, mature fruiting and fruit dehiscence. Full article |
Solid red symbols are species mean with ± standard error for each reproductive phenology event across altitude. Black solid line shows trend in abiotic variables with phenology events as shown by simple linear regression, and gray dashed line shows trend in abiotic variables with phenology events as shown by phylogenetic generalized least square regression.
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2. Phenology determines leaf functional traits across Rhododendron species
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Relationship of leaf traits with elevation. The point represents the individual values per species for each elevation and the solid line with gray loess curves shows trend in leaf traits with elevation measured using linear mixed model
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Fruit/flower ratio under four different treatments in the pollination experiment for aR. hodgsonii, bR. thomsonii, cR. campanulatum, dR. campylocarpum, eR. cinnabarinum, fR. aeruginousm, gR. wightii, hR. anthopogon, iR. setosum, jR. lepidotum. The asterisk (*) sign shows significant variation between pollination treatment and the control treatment. *P < 0.05, **P < 0.01, ***P < 0.001
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3. Floral traits determine pollinator visitation in Rhododendron species across an elevation gradient
This study shows the association of floral characteristics with pollinators in response to elevation. Corolla length, nectar volume, and distance between stamen and stigma significantly decreased with elevation. Bird visits showed a strong negative association with elevation, while visits by bumblebees and flies increased with elevation. Species with longer corollas and higher nectar volumes showed higher rates of bird visits. At the same time, bumblebees were associated with species that had higher nectar concentrations. Finally, fruit set following cross-pollination was higher than self-pollination. Full article |
4. Floral traits and community phylogenetic structure shape plant-pollinator interactions in co-occurring Rhododendrons
The study demonstrates that the Rhododendron community is structured at lower elevations by both facilitation and competition. In contrast, communities in the transition zone and higher elevations are structured by competition alone. Furthermore, a clustered phylogenetic structure was predominately observed in lower-elevation Rhododendron communities. A dispersed and random phylogenetic structure was observed in the transition zone and at higher elevations. Full article |
Phylogenetic relationship and floral trait diversity in ten Rhododendron species. Stochastic mapping of nectar volume and concentration are visualized as different colors along nodes and branches of the phylogeny.
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