Rajasri Ray - Academia.edu (original) (raw)

Papers by Rajasri Ray

Fascinating life sciences, 2022

Temporal fluctuations in effective population size assuming a generation time of eight years and ... more Temporal fluctuations in effective population size assuming a generation time of eight years and a mutation rate of 2.2 X 10^-9 per base pair per year. Estimates based on complete data and bootstraps are depicted in dark and light red color, respectively.

Journal of Genetics, 2021

The apparent absence of Himalayan low-elevation taxa in the central Indian region and resumption ... more The apparent absence of Himalayan low-elevation taxa in the central Indian region and resumption of their distribution in the high elevation of Western Ghats has puzzled biogeographers for several decades. Many theories have been proposed to explain this but attempts remain futile owing to insufficient empirical support. Here, we have employed a montane tree species, Rhododendron arboreum to investigate this pattern by integrating past ecological niche modelling with molecular signatures. Reconstruction of paleo-ecological niche from interglacial to Last Glacial Maxima (LGM) portrayed a gradual depletion of vegetation cover with extreme impoverishment in the Holocene. A similar pattern was also reflected from genetic signatures; population history revealed a very recent split between the Himalayas and Western Ghats in the late Quaternary. A few other tree species exhibiting the same disjunction demonstrated a similar modification of paleo-ecological niche from last interglacial. The...

A tri-monthly newsletter published by Centre for Studies in Ethnobiology, Biodiversity and Sustai... more A tri-monthly newsletter published by Centre for Studies in Ethnobiology, Biodiversity and Sustainability (CEiBa) that focuses on a diverse array of topics, mostly covering ecology and environment, natural and cultural history to oral history, and conservation. The purpose is to introduce awe-inspiring facets of natural or semi-natural world to a broader group of readers who tend to distance themselves owing to the inherent complexities of dry scientific findings. Moreover, it is also a vehicle of communication for aspiring scholars who wish to share their fascinating ‘research stories’.
CEiBa is a non-profit research and education center (registered under the Indian Trust Act, 1882) and its activity hinges on various aspects of the human-nature interface, bio-cultural diversity, and the path to sustainability.

Location points used for niche modeling

Temporal fluctuations in effective population size assuming a generation time of two years and a ... more Temporal fluctuations in effective population size assuming a generation time of two years and a mutation rate of 2.2 X 10^-9 per base pair per year. Estimates based on complete data and bootstraps are depicted in dark and light red color, respectively.

Details of raw genome data, sampling, diet, forearm length and body mass for each study species

Gondwana break-up is one of the key sculptors of the global biogeographic pattern including India... more Gondwana break-up is one of the key sculptors of the global biogeographic pattern including Indian subcontinent. Myrtaceae, a Gondwana family, demonstrates a high diversity across Indian Western Ghats. A rich paleo-records in Deccan Intertrappean bed in India strive to reconcile two contending hypothesis of origin and diversification of Myrtaceae in India, namely Gondwana elements floated on peninsular India or lineages invading from south-east Asia. In this study, we have reconstructed the biogeographic history of Myrtaceae of Western Ghats of India combining fossil-calibrated phylogeny, ancestral area reconstruction, and comparing various dispersal models.Phylogenetic reconstructions divided lineages into multiple clades at the tribal level that mostly is in agreement with previous descriptions. Dated tree indicated a presumable Gondwanan origin of Myrtaceae (95.7 Ma). The Western Ghats taxa are relatively younger and seem to have arrived either through long-distance oceanic dispe...

Over the last approximately 2.6 Myr, Earth's climate has been dominated by cyclical ice ages ... more Over the last approximately 2.6 Myr, Earth's climate has been dominated by cyclical ice ages that have profoundly affected species' population sizes, but the impact of impending anthropogenic climate change on species' extinction potential remains a worrying problem. We investigated 11 bat species from different taxonomic, ecological and geographical backgrounds using combined information from palaeoclimatic habitat reconstructions and genomes to analyse biotic impacts of historic climate change. We discover tightly correlated fluctuations between species' historic distribution and effective population size, identify frugivores as particularly susceptible to global warming, pinpoint large insectivores as having overall low effective population size and flag the onset of the Holocene (approx. 10–12 000 years ago) as the period with the generally lowest effective population sizes across the last approximately 1 Myr. Our study shows that combining genomic and palaeoclimatological approaches reveals effects of climatic shifts on genetic diversity and may help predict impacts of future climate change.

Citation: Ray A, Ray R and Sreevidya EA (2021) Corrigendum: How Many Wild Edible Plants Do We Eat... more Citation: Ray A, Ray R and Sreevidya EA (2021) Corrigendum: How Many Wild Edible Plants Do We Eat—Their Diversity, Use, and Implications for Sustainable Food System: An Exploratory Analysis in India. Front. Sustain. Food Syst. 5:667541. doi: 10.3389/fsufs.2021.667541 Corrigendum: How Many Wild Edible Plants Do We Eat—Their Diversity, Use, and Implications for Sustainable Food System: An Exploratory Analysis in India

Ethnobotany Research and Applications, 2020

Background : Sacred groves are model systems that have the potential to contribute to rural healt... more Background : Sacred groves are model systems that have the potential to contribute to rural healthcare owing to their medicinal floral diversity and strong social acceptance. Methods: We examined this idea employing ethnomedicinal plants and their application documented from sacred groves across India. A total of 65 published documents were shortlisted for the preparation of database and statistical analysis. Standard ethnobotanical indices and mapping were used to capture the current trend. Results: A total of 1247 species from 152 families has been documented for use against eighteen categories of diseases common in tropical and sub-tropical landscapes. Though the reported species are clustered around a few widely distributed families, 71% of them are uniquely represented from any single biogeographic region. The use of multiple species in treating an ailment, high use value of the popular plants, and cross-community similarity in disease treatment reflects rich community wisdom ...

Frontiers in Sustainable Food Systems, 2020

Wild edible plants are still eaten by a large section of the global population and ensure both af... more Wild edible plants are still eaten by a large section of the global population and ensure both affordable food and nutritional security. We tested this in an Indian context, where an enormous diversity of such plants constitutes a significant part of the rural diet and their acceptance has been high. In this study, we assessed the diversity of wild edible plant resource and the importance of species based on the use and its pattern. We have also shortlisted a set of plants to make an informed decision on prioritization. We found a great variety of plants (1,403 species) from 184 families were consumed across India, although the first 44 families (24%) contributed largely to the (75%) diversity. Leguminosae followed by Compositae, Poaceae, Malvaceae, and Rosaceae, were the families with the highest number of species. We note that a few species from the large pool were extensively used throughout the country while another few were valued for their multiple edible plant parts. Leafy sh...

Syzygium Gaertn. is the largest woody genus of flowering plants in the world. Unpublished but ext... more Syzygium Gaertn. is the largest woody genus of flowering plants in the world. Unpublished but extensive recent herbarium surveys suggest 1200‒1800 species distributed throughout the Old World tropics and subtropics (Table 1). Until recently, Syzygium exemplified a recurring taxonomic impediment among megadiverse genera, wherein few taxonomists worked on the group in any sustained manner, a majority of the herbarium specimens remained undetermined or misidentified, few if any attempts were made to look at the genus globally, and limited or no molecular studies were available to provide a predictive phylogenetic context of the genus. The situation with Syzygium has slowly begun to change as allied genera have been absorbed into the genus (Biffin et al., 2006; Craven & Biffin, 2010), and predictive phylogenetically-based infrageneric classifications are emerging. Taxonomic outputs on Syzygium also have been increasing across its range with the description of new species, resolution of ...

The climatic shifts in the Quaternary Period acted as an important driving force for evolution of... more The climatic shifts in the Quaternary Period acted as an important driving force for evolution of the world's biodiversity. In this study, responses to the ice age of a rare and endangered tree of Indian Western Ghats, Syzygium travancoricum, was investigated through a combination of molecular data and ecological niche modeling.Results indicate the moderate (nrDNA) to high (cpDNA) population structure, presence of private alleles, and absence of phylogeographic structure. Spatial distribution of diversity does not signifi- cantly support southern colonisation, nor the Palghat Gap as a geographical barrier based on the genetic structure. Combined insights from Ecological Niche Modelling and population history de- picts a probable colonisation of the Western Ghats in the late Miocene or later followed by a split into separate southern and northern populations from the middle to late Pleistocene. The prevalence of favourable conditions in the post-Last interglacial period stimulate...

Proceedings of the Royal Society B: Biological Sciences, 2019

Over the last approximately 2.6 Myr, Earth's climate has been dominated by cyclical ice ages ... more Over the last approximately 2.6 Myr, Earth's climate has been dominated by cyclical ice ages that have profoundly affected species' population sizes, but the impact of impending anthropogenic climate change on species’ extinction potential remains a worrying problem. We investigated 11 bat species from different taxonomic, ecological and geographical backgrounds using combined information from palaeoclimatic habitat reconstructions and genomes to analyse biotic impacts of historic climate change. We discover tightly correlated fluctuations between species' historic distribution and effective population size, identify frugivores as particularly susceptible to global warming, pinpoint large insectivores as having overall low effective population size and flag the onset of the Holocene (approx. 10–12 000 years ago) as the period with the generally lowest effective population sizes across the last approximately 1 Myr. Our study shows that combining genomic and palaeoclimatol...

Present work has been conducted on in vitro conservation of a rare medicinal plant, Plumbago indi... more Present work has been conducted on in vitro conservation of a rare medicinal plant, Plumbago indica, through storage of germplasms derived from micropropagated progenies of the species. Direct regeneration of axillary shoots and their multiplication have been optimized using BAP at a concentration of 2.0 mg/1 in MS with 3% sucrose. Plantlets with profusely growing roots, induced by 1.0 mg/1 putrescine have been transferred successfully to natural environment as evident from their high survival rate. In vitro storage of P. indica has been developed by (1) reduced growth culture of shoot apex explants for prolonged period without periodic transfer and (2) by preserving encapsulated in vitro generated propagulcs (artiicial seed) for a short term period. Combined application of mannitol (3%) and BAP (2.0 mg/1) resulted in significant reduction in growth rate. After 12 months of storage, cultures survived with 100% success by re-growing in regeneration medium. The alginate-coated beads, ...

The agenda on conservation of biodiversity usually inclines towards exclusionary approaches like ... more The agenda on conservation of biodiversity usually inclines towards exclusionary approaches like protected area, reserve forest, national parks etc. However, recent findings indicate the importance of humanised landscape in this regard due to simultaneous operations of life supporting activities at various scale. Humanised landscape supports various life forms at different levels although magnitude of human intervention has paramount importance in this regard. Although, theoretical underpinning on these issues are better resolved, empirical findings are very much context and area specific even incomplete to some extent due to lack of detail knowledge on species interaction with nature. Recent technological advancements (e.g. GIS and remote sensing, niche modelling and con-nectivity analysis) offer ample opportunities to study various aspects of species life cycle and its association with landscape, thus resolving problems related to species management. This article deals with few ca...

Fascinating life sciences, 2022

Temporal fluctuations in effective population size assuming a generation time of eight years and ... more Temporal fluctuations in effective population size assuming a generation time of eight years and a mutation rate of 2.2 X 10^-9 per base pair per year. Estimates based on complete data and bootstraps are depicted in dark and light red color, respectively.

Journal of Genetics, 2021

The apparent absence of Himalayan low-elevation taxa in the central Indian region and resumption ... more The apparent absence of Himalayan low-elevation taxa in the central Indian region and resumption of their distribution in the high elevation of Western Ghats has puzzled biogeographers for several decades. Many theories have been proposed to explain this but attempts remain futile owing to insufficient empirical support. Here, we have employed a montane tree species, Rhododendron arboreum to investigate this pattern by integrating past ecological niche modelling with molecular signatures. Reconstruction of paleo-ecological niche from interglacial to Last Glacial Maxima (LGM) portrayed a gradual depletion of vegetation cover with extreme impoverishment in the Holocene. A similar pattern was also reflected from genetic signatures; population history revealed a very recent split between the Himalayas and Western Ghats in the late Quaternary. A few other tree species exhibiting the same disjunction demonstrated a similar modification of paleo-ecological niche from last interglacial. The...

A tri-monthly newsletter published by Centre for Studies in Ethnobiology, Biodiversity and Sustai... more A tri-monthly newsletter published by Centre for Studies in Ethnobiology, Biodiversity and Sustainability (CEiBa) that focuses on a diverse array of topics, mostly covering ecology and environment, natural and cultural history to oral history, and conservation. The purpose is to introduce awe-inspiring facets of natural or semi-natural world to a broader group of readers who tend to distance themselves owing to the inherent complexities of dry scientific findings. Moreover, it is also a vehicle of communication for aspiring scholars who wish to share their fascinating ‘research stories’.
CEiBa is a non-profit research and education center (registered under the Indian Trust Act, 1882) and its activity hinges on various aspects of the human-nature interface, bio-cultural diversity, and the path to sustainability.

Location points used for niche modeling

Temporal fluctuations in effective population size assuming a generation time of two years and a ... more Temporal fluctuations in effective population size assuming a generation time of two years and a mutation rate of 2.2 X 10^-9 per base pair per year. Estimates based on complete data and bootstraps are depicted in dark and light red color, respectively.

Details of raw genome data, sampling, diet, forearm length and body mass for each study species

Gondwana break-up is one of the key sculptors of the global biogeographic pattern including India... more Gondwana break-up is one of the key sculptors of the global biogeographic pattern including Indian subcontinent. Myrtaceae, a Gondwana family, demonstrates a high diversity across Indian Western Ghats. A rich paleo-records in Deccan Intertrappean bed in India strive to reconcile two contending hypothesis of origin and diversification of Myrtaceae in India, namely Gondwana elements floated on peninsular India or lineages invading from south-east Asia. In this study, we have reconstructed the biogeographic history of Myrtaceae of Western Ghats of India combining fossil-calibrated phylogeny, ancestral area reconstruction, and comparing various dispersal models.Phylogenetic reconstructions divided lineages into multiple clades at the tribal level that mostly is in agreement with previous descriptions. Dated tree indicated a presumable Gondwanan origin of Myrtaceae (95.7 Ma). The Western Ghats taxa are relatively younger and seem to have arrived either through long-distance oceanic dispe...

Over the last approximately 2.6 Myr, Earth's climate has been dominated by cyclical ice ages ... more Over the last approximately 2.6 Myr, Earth's climate has been dominated by cyclical ice ages that have profoundly affected species' population sizes, but the impact of impending anthropogenic climate change on species' extinction potential remains a worrying problem. We investigated 11 bat species from different taxonomic, ecological and geographical backgrounds using combined information from palaeoclimatic habitat reconstructions and genomes to analyse biotic impacts of historic climate change. We discover tightly correlated fluctuations between species' historic distribution and effective population size, identify frugivores as particularly susceptible to global warming, pinpoint large insectivores as having overall low effective population size and flag the onset of the Holocene (approx. 10–12 000 years ago) as the period with the generally lowest effective population sizes across the last approximately 1 Myr. Our study shows that combining genomic and palaeoclimatological approaches reveals effects of climatic shifts on genetic diversity and may help predict impacts of future climate change.

Citation: Ray A, Ray R and Sreevidya EA (2021) Corrigendum: How Many Wild Edible Plants Do We Eat... more Citation: Ray A, Ray R and Sreevidya EA (2021) Corrigendum: How Many Wild Edible Plants Do We Eat—Their Diversity, Use, and Implications for Sustainable Food System: An Exploratory Analysis in India. Front. Sustain. Food Syst. 5:667541. doi: 10.3389/fsufs.2021.667541 Corrigendum: How Many Wild Edible Plants Do We Eat—Their Diversity, Use, and Implications for Sustainable Food System: An Exploratory Analysis in India

Ethnobotany Research and Applications, 2020

Background : Sacred groves are model systems that have the potential to contribute to rural healt... more Background : Sacred groves are model systems that have the potential to contribute to rural healthcare owing to their medicinal floral diversity and strong social acceptance. Methods: We examined this idea employing ethnomedicinal plants and their application documented from sacred groves across India. A total of 65 published documents were shortlisted for the preparation of database and statistical analysis. Standard ethnobotanical indices and mapping were used to capture the current trend. Results: A total of 1247 species from 152 families has been documented for use against eighteen categories of diseases common in tropical and sub-tropical landscapes. Though the reported species are clustered around a few widely distributed families, 71% of them are uniquely represented from any single biogeographic region. The use of multiple species in treating an ailment, high use value of the popular plants, and cross-community similarity in disease treatment reflects rich community wisdom ...

Frontiers in Sustainable Food Systems, 2020

Wild edible plants are still eaten by a large section of the global population and ensure both af... more Wild edible plants are still eaten by a large section of the global population and ensure both affordable food and nutritional security. We tested this in an Indian context, where an enormous diversity of such plants constitutes a significant part of the rural diet and their acceptance has been high. In this study, we assessed the diversity of wild edible plant resource and the importance of species based on the use and its pattern. We have also shortlisted a set of plants to make an informed decision on prioritization. We found a great variety of plants (1,403 species) from 184 families were consumed across India, although the first 44 families (24%) contributed largely to the (75%) diversity. Leguminosae followed by Compositae, Poaceae, Malvaceae, and Rosaceae, were the families with the highest number of species. We note that a few species from the large pool were extensively used throughout the country while another few were valued for their multiple edible plant parts. Leafy sh...

Syzygium Gaertn. is the largest woody genus of flowering plants in the world. Unpublished but ext... more Syzygium Gaertn. is the largest woody genus of flowering plants in the world. Unpublished but extensive recent herbarium surveys suggest 1200‒1800 species distributed throughout the Old World tropics and subtropics (Table 1). Until recently, Syzygium exemplified a recurring taxonomic impediment among megadiverse genera, wherein few taxonomists worked on the group in any sustained manner, a majority of the herbarium specimens remained undetermined or misidentified, few if any attempts were made to look at the genus globally, and limited or no molecular studies were available to provide a predictive phylogenetic context of the genus. The situation with Syzygium has slowly begun to change as allied genera have been absorbed into the genus (Biffin et al., 2006; Craven & Biffin, 2010), and predictive phylogenetically-based infrageneric classifications are emerging. Taxonomic outputs on Syzygium also have been increasing across its range with the description of new species, resolution of ...

The climatic shifts in the Quaternary Period acted as an important driving force for evolution of... more The climatic shifts in the Quaternary Period acted as an important driving force for evolution of the world's biodiversity. In this study, responses to the ice age of a rare and endangered tree of Indian Western Ghats, Syzygium travancoricum, was investigated through a combination of molecular data and ecological niche modeling.Results indicate the moderate (nrDNA) to high (cpDNA) population structure, presence of private alleles, and absence of phylogeographic structure. Spatial distribution of diversity does not signifi- cantly support southern colonisation, nor the Palghat Gap as a geographical barrier based on the genetic structure. Combined insights from Ecological Niche Modelling and population history de- picts a probable colonisation of the Western Ghats in the late Miocene or later followed by a split into separate southern and northern populations from the middle to late Pleistocene. The prevalence of favourable conditions in the post-Last interglacial period stimulate...

Proceedings of the Royal Society B: Biological Sciences, 2019

Over the last approximately 2.6 Myr, Earth's climate has been dominated by cyclical ice ages ... more Over the last approximately 2.6 Myr, Earth's climate has been dominated by cyclical ice ages that have profoundly affected species' population sizes, but the impact of impending anthropogenic climate change on species’ extinction potential remains a worrying problem. We investigated 11 bat species from different taxonomic, ecological and geographical backgrounds using combined information from palaeoclimatic habitat reconstructions and genomes to analyse biotic impacts of historic climate change. We discover tightly correlated fluctuations between species' historic distribution and effective population size, identify frugivores as particularly susceptible to global warming, pinpoint large insectivores as having overall low effective population size and flag the onset of the Holocene (approx. 10–12 000 years ago) as the period with the generally lowest effective population sizes across the last approximately 1 Myr. Our study shows that combining genomic and palaeoclimatol...

Present work has been conducted on in vitro conservation of a rare medicinal plant, Plumbago indi... more Present work has been conducted on in vitro conservation of a rare medicinal plant, Plumbago indica, through storage of germplasms derived from micropropagated progenies of the species. Direct regeneration of axillary shoots and their multiplication have been optimized using BAP at a concentration of 2.0 mg/1 in MS with 3% sucrose. Plantlets with profusely growing roots, induced by 1.0 mg/1 putrescine have been transferred successfully to natural environment as evident from their high survival rate. In vitro storage of P. indica has been developed by (1) reduced growth culture of shoot apex explants for prolonged period without periodic transfer and (2) by preserving encapsulated in vitro generated propagulcs (artiicial seed) for a short term period. Combined application of mannitol (3%) and BAP (2.0 mg/1) resulted in significant reduction in growth rate. After 12 months of storage, cultures survived with 100% success by re-growing in regeneration medium. The alginate-coated beads, ...

The agenda on conservation of biodiversity usually inclines towards exclusionary approaches like ... more The agenda on conservation of biodiversity usually inclines towards exclusionary approaches like protected area, reserve forest, national parks etc. However, recent findings indicate the importance of humanised landscape in this regard due to simultaneous operations of life supporting activities at various scale. Humanised landscape supports various life forms at different levels although magnitude of human intervention has paramount importance in this regard. Although, theoretical underpinning on these issues are better resolved, empirical findings are very much context and area specific even incomplete to some extent due to lack of detail knowledge on species interaction with nature. Recent technological advancements (e.g. GIS and remote sensing, niche modelling and con-nectivity analysis) offer ample opportunities to study various aspects of species life cycle and its association with landscape, thus resolving problems related to species management. This article deals with few ca...