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1.
Anat Histol Embryol ; 53(3): e13031, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38519866

RESUMEN

Cranial measurements have been widely used in various studies in wildlife sciences, ranging from understanding predator ecology to wildlife forensics. However, detailed description of morphometry and sexual dimorphism of the skull of gaur Bos gaurus gaurus is lacking. The present study was undertaken to determine the sexual dimorphism based on the cranial measurements of gaur. A total of 12 individual gaur skulls of male (n = 6) and female (n = 6) were studied in the field from the naturally deceased animals between January 2018 and December 2021 in different ranges of Bandhavgarh tiger reserve (BTR), Madhya Pradesh, India. The skull measurements were analysed using univariate and multivariate statistics to determine whether cranial dimensions could be used to differentiate male and female skulls reliably. A total of 43 morphometrical parameters grouped into nine indices were calculated. Select morphometrical parameters viz PL, GFL, AKI, LBB, LFB, GBEE, GBAN, BPOP and GTCH were significantly different (p < 0.05) between sexes, whereas GBAN were significantly higher in female skulls. The measurements demonstrated that the skull of the gaur was dolichocephalic as the profile length and the otion to otion breath in both male and female were <75% of the length. Overall, 28 linear measurements of both the sexes were statistically significant (p < 0.05; <0.01). The calculated indices revealed that the foramen magnum index in the female gaur were significantly higher. In calculated cranial indices the facial index (a) was higher in female and facial index (b) were higher in males. The two important parameters, facial breadth in facial index (a) and the greatest breadth in facial index (b) were positively correlated, though facial index (a) was statistically not significant between the sexes. The greater inner length of the foramen magnum in female skull resulted in foramen being oval whereas it was circular in males. These parameters were decisive for sexual dimorphism, skull comparison and craniological studies. This study ascertained that the frontal index and skull index had no significant influence and were not good indices for discriminating skulls between male and female. Based on the Principal Component Analysis, it was found that skull of male and female gaurs exhibits differences in cranial morphology viz. cranial profile length or total length (PL) and the least inner height of the temporal groove (LIHT). The findings of the present study provide baseline information on various craniometrical measurements of skull of gaur, indices and parameters for sex identification that can be effectively used in understanding sex biased predation ecology, provide base line information to describe variation across its geographic range, and in identifying skulls recovered in wildlife offence cases.


Asunto(s)
Caracteres Sexuales , Cráneo , Masculino , Femenino , Animales , Bovinos , Cráneo/anatomía & histología , Cefalometría/veterinaria , Foramen Magno/anatomía & histología , Animales Salvajes
2.
PeerJ ; 11: e15914, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38025689

RESUMEN

Background: Large carnivores play a crucial role in maintaining the balance of the ecosystem. Successful conservation initiatives have often led to a huge increase in predators which has often led to negative interactions with humans. Without the knowledge of the carrying capacity of the top predator, such decisions become challenging. Here, we have derived a new equation to estimate the carrying capacity of tigers based on the individual prey species density. Methods: We used tiger densities and respective prey densities of different protected areas. Relative prey abundance was used instead of absolute prey density as this could be a better surrogate of the prey preference. We used a regression approach to derive the species-wise equation. We have also scaled these coefficients accordingly to control the variation in the standard error (heteroscedasticity) of the tiger density. Furthermore, we have extended this regression equation for different species to different weight classes for more generalized application of the method. Results: The new equations performed considerably better compared to the earlier existing carrying capacity equations. Incorporating the species-wise approach in the equation also reflected the preference of the prey species for the tiger. This is the first carrying capacity equation where the individual prey densities are used to estimate the carnivore population density. The coefficient estimates of the model with the comparison with prey-predator power laws also reflect the differential effect of tigers on different prey species. The carrying capacity estimates will aid in a better understanding of the predator-prey interaction and will advance better management of the top predator.


Asunto(s)
Carnívoros , Tigres , Animales , Humanos , Ecosistema , Conservación de los Recursos Naturales , Densidad de Población
3.
PeerJ ; 11: e15746, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37872949

RESUMEN

Background: The Kashmir red deer or Hangul (Cervus hanglu hanglu) is the only Tarim red deer species endemic to India. With a current estimated population size of fewer than 200 individuals, this critically endangered species is confined to the greater Dachigam landscape in Jammu and Kashmir. Poaching, habitat loss and fragmentation, resource competition with livestock, and small population size are the major conservation challenges for this species. Methods: Blood sampling was conducted from two wild Hangul individuals during radio-collaring operations at Dachigam National Park, Kashmir in 2013 and 2020, respectively. Using next-generation sequencing approach, we sequenced the 16,351 bp long mitogenome of two wild-caught Hangul individuals (1 M:1 F at ~14× and ~10× coverage, respectively) from Dachigam National Park. Results: The annotated sequences were identical with an AT-rich composition, including 13 protein-coding genes (11,354 bp), 22 tRNA genes (1,515 bp), two ribosomal genes (2,526 bp) and a non-coding control region (917 bp) in a conserved order like other red deer species. Bayesian phylogenetic reconstruction of the red deer complex revealed two major groups: the elaphoid and the wapitoid clades. Hangul formed a distinct clade with its other subspecies C. hanglu yarkandensis and is sister to the Hungarian red deer (C. elaphus hippelaphus). Divergence time analyses suggested that the Tarim deer species group separated ~1.55 Mya from their common ancestors and Hangul diverged ~0.75 Mya from closely related C. yarkandensis, corroborating with the known paleobiogeographic events related to refugia during glaciations in the Pleistocene era. This study provides baseline information on Hangul mitogenome for further research on phylogeography and other population parameters and helps in developing suitable conservation plans for this species.


Asunto(s)
Ciervos , Animales , Filogenia , Teorema de Bayes , Ciervos/genética , Evolución Biológica , Filogeografía
4.
Ecol Evol ; 12(9): e9307, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36188506

RESUMEN

Conservation of wide-ranging species and their movement is a major challenge in an increasingly fragmented world. Long-distance movement, such as dispersal, is a key factor for the persistence of population, enabling the movement of animals within and between populations. Here, we describe one of the longest dispersal journeys by a sub-adult male tiger (Panthera tigris) through GPS telemetry in Central India. We analyzed movement metrics, directionality, and space use during three behavioral stages of dispersal. We also used the clustering method to identify resting and kill sites (n = 89). T1-C1 dispersed a straight-line distance of 315 km over 225 days, moving an average of 8.38 km/day and covering a cumulative displacement of ~3000 km. Movement rate during post-dispersal was faster (mean = 0.47 km/h) than during dispersal (mean = 0.38 km/h) and pre-dispersal (mean = 0.13 km/h), respectively. The overall movement rate during the night (0.44 km/h) was significantly faster than during the day (0.21 km/h). Likewise, during dispersal, the movement was faster (mean = 0.52 km/h) at night than day (0.24 km/h). The average size of clusters, signifying resting and kill sites, was 1.68 ha and primarily away from human habitation (mean = 1.89 km). The individual crossed roads faster (mean = 2.00 km/h) than it traveled during other times. During the post-dispersal phase, T1-C1 had a space use of 319.48 km2 (95% dBBMM) in the Dnyanganga Wildlife Sanctuary. The dispersal event highlights the long-distance and multiscale movement behavior in a heterogeneous landscape. Moreover, small forest patches play a key role in maintaining large carnivore connectivity while dispersing through a human-dominated landscape. Our study underlines how documenting the long-distance movement and integrating it with modern technology can improve conservation management decisions.

5.
Sci Rep ; 12(1): 14029, 2022 08 18.
Artículo en Inglés | MEDLINE | ID: mdl-35982090

RESUMEN

Studies on resource utilisation by carnivores are essential as they aid in assessing their role in a community, by unravelling predator-prey relationships. Globally, prey depletion is one of the primary causes of declining Asiatic wild dog (dhole) populations. Therefore, it is essential to examine their diet across their range. Our study presents insights into dhole feeding ecology across multiple sites from the central Indian landscape of Maharashtra, India, for the first time. We conducted scat analysis using a subset of genetically identified scats and collected additional data from kills observed while tracking radio-collared dholes and other known packs from 2 study sites. We analysed 861 scats, and 191 dhole kills to identify species and age class of prey. We estimated the relative contribution of various prey, utilising non-linear biomass models of prey consumption. Overall, wild ungulates like sambar and chital were the principal prey in terms of biomass (sambar 61.08%; chital 19.08%) and number of prey consumed (sambar 39.28%; chital 13.83%). An analysis of kill data also suggested that dholes strongly preferred the two deer species; and differential selection of age classes was observed at the 2 study sites. Our study can potentially help manage and conserve this important population of an endangered carnivore.


Asunto(s)
Canidae , Carnívoros , Ciervos , Animales , Ecología , Bosques , India , Conducta Predatoria
6.
Proc Natl Acad Sci U S A ; 118(49)2021 12 07.
Artículo en Inglés | MEDLINE | ID: mdl-34848534

RESUMEN

Increasing habitat fragmentation leads to wild populations becoming small, isolated, and threatened by inbreeding depression. However, small populations may be able to purge recessive deleterious alleles as they become expressed in homozygotes, thus reducing inbreeding depression and increasing population viability. We used whole-genome sequences from 57 tigers to estimate individual inbreeding and mutation load in a small-isolated and two large-connected populations in India. As expected, the small-isolated population had substantially higher average genomic inbreeding (FROH = 0.57) than the large-connected (FROH = 0.35 and FROH = 0.46) populations. The small-isolated population had the lowest loss-of-function mutation load, likely due to purging of highly deleterious recessive mutations. The large populations had lower missense mutation loads than the small-isolated population, but were not identical, possibly due to different demographic histories. While the number of the loss-of-function alleles in the small-isolated population was lower, these alleles were at higher frequencies and homozygosity than in the large populations. Together, our data and analyses provide evidence of 1) high mutation load, 2) purging, and 3) the highest predicted inbreeding depression, despite purging, in the small-isolated population. Frequency distributions of damaging and neutral alleles uncover genomic evidence that purifying selection has removed part of the mutation load across Indian tiger populations. These results provide genomic evidence for purifying selection in both small and large populations, but also suggest that the remaining deleterious alleles may have inbreeding-associated fitness costs. We suggest that genetic rescue from sources selected based on genome-wide differentiation could offset any possible impacts of inbreeding depression.


Asunto(s)
Variación Genética , Genómica , Endogamia , Tigres/genética , Distribución Animal , Animales , Conservación de los Recursos Naturales , Genoma , India
7.
Sci Rep ; 11(1): 16371, 2021 08 12.
Artículo en Inglés | MEDLINE | ID: mdl-34385570

RESUMEN

Deforestation and agricultural intensification have resulted in an alarming change in the global land cover over the past 300 years, posing a threat to species conservation. Dhole is a monophyletic, social canid and, being an endangered and highly forest-dependent species, is more prone to the loss of favorable habitat in the Anthropocene. We determined the genetic differentiation and demographic history of dhole across the tiger reserves of Maharashtra using the microsatellite data of 305 individuals. Simulation-based analyses revealed a 77-85% decline in the major dhole sub-populations. Protected areas have provided refuge to the historically declining dhole population resulting in clustering with strong genetic structure in the remnant dhole population. The historical population decline coincides with the extreme events in the landscape over the past 300 years. The study highlights the pattern of genetic differentiation and diversity of a highly forest-dependent species which can be associated with the loss of forest cover outside tiger reserves. It also warrants attention to develop conservation plans for the remnant surviving population of dholes in India.


Asunto(s)
Animales Salvajes/genética , Carnívoros/genética , Perros/genética , Variación Genética/genética , Animales , Conservación de los Recursos Naturales/métodos , Demografía/métodos , Ecosistema , Especies en Peligro de Extinción , Bosques , India , Repeticiones de Microsatélite/genética , Tigres/genética
8.
Ecol Evol ; 11(9): 4774-4785, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33976847

RESUMEN

In multipredator systems, group sizes of social carnivores are shaped by the asymmetric intraguild interactions. Subordinate social carnivores experience low recruitment rates as an outcome of predation pressure. In South and Southeast Asia, the Tiger (Panthera tigris), Dhole (Cuon alpinus), and Leopard (Panthera pardus) form a widely distributed sympatric guild of large carnivores, wherein tigers are the apex predators followed by dhole and leopard. In this study, we attempted to understand the variation in pack size of a social carnivore, the dhole, at two neighboring sites in the Central Indian landscape. We further evaluated local-scale patterns of variation in pack size at a larger scale by doing a distribution-wide assessment across the dhole ranging countries. At the local scale, we found an inverse relationship between the density of tiger and pack size of dhole while accounting for variability in resources and habitat heterogeneity. Larger dhole packs (16.8 ± 3.1) were observed at the site where the tiger density was low (0.46/100 km2), whereas a smaller pack size (6.4 ± 1.3) was observed in the site with high tiger density (5.36/100 km2). Our results for the distribution-wide assessment were concordant with local-scale results, showing a negative association of pack size with the tiger densities (effect size -0.77) and a positive association with the prey abundance (effect size 0.64). The study advances our understanding to answer the age-old question of "what drives the pack size of social predators in a multipredator system?" This study also highlights the importance of understanding demographic responses of subordinate predator for varying competitor densities, often helpful in making informed decisions for conservation and management strategies such as population recovery and translocation of species.

9.
Mol Biol Rep ; 48(2): 1995-2003, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33527322

RESUMEN

The wild water buffalo (Bubalus arnee) is one of the most endangered and least studied large bovid in the Indian subcontinent. India retains 90% of the estimated global population of >4000 individuals as two fragmented populations in Assam and Chhattisgarh, both threatened by habitat loss and degradation, hunting, disease from livestock, and hybridization with the domestic buffalos. Small, fragmented population size and potential hybridisation pressures from co-occurring domestic buffalos are the major conservation challenges. For the first time, we sequenced the 16,357 bp long mitogenome of three opportunistically collected wild water buffalo samples from Assam (n = 1) and Chhattishgarh (n = 2). The annotated sequence has a base composition of 26.4% T, 26.6% C, 33.1% A and 13.9% G depicting an AT-rich mitogenome composition, including 13 protein-coding genes (11,361 bp), 22 transfer RNA (tRNA) (1514 bp), two ribosomal genes (2525 bp), and a non-coding control region (928 bp). The gene order is conserved with other bovid species. Comparative mitogenome analyses showed both populations are genetically similar but significantly different from domestic buffalo. We also identified structural differences in seven tRNA secondary structures between both species. The genetic distance between wild buffalo and other bovids varied between 0.103 and 0.122. Multiple Bayesian phylogenetic trees showed that both wild and domestic water buffalo formed sister clades which were paraphyletic to other potentially sympatric species of genus Bos. This study provides baseline information on wild buffalo mitogenome for further research on phylogeny, phylogeography and hybrid assessment and help conserving this endangered species.


Asunto(s)
Búfalos/genética , ADN Mitocondrial/genética , Especies en Peligro de Extinción , Genoma Mitocondrial , Animales , Teorema de Bayes , Bovinos , Clasificación , Genes de ARNr , Variación Genética , India , Proteínas Mitocondriales/genética , Filogenia , Filogeografía , Reacción en Cadena de la Polimerasa , ARN de Transferencia/química , ARN de Transferencia/genética , Análisis de Secuencia de ADN
10.
Ecol Evol ; 11(4): 1653-1666, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33613996

RESUMEN

Large carnivores play an important role in the functioning of ecosystems, yet their conservation remains a massive challenge across the world. Owing to wide-ranging habits, they encounter various anthropogenic pressures, affecting their movement in different landscape. Therefore, studying how large carnivores adapt their movement to dynamic landscape conditions is vital for management and conservation policy. A total of 26 individuals across 4 species of large carnivores of different sex and age classes (14 Panthera tigris, 3 Panthera pardus, 5 Cuon alpinus, and 4 Canis lupus pallipes) were GPS collared and monitored from 2014-19. We quantified movement parameters (step length and net squared displacement) of four large carnivores in and outside protected areas in India. We tested the effects of human pressures such as human density, road network, and landuse types on the movement of the species. We also examined the configuration of core areas as a strategy to subsist in a human-dominated landscape using BBMM. Mean displacement of large carnivores varied from 99.35 m/hr for leopards to 637.7 m/hr for wolves. Tigers outside PAs exhibited higher displacement than tigers inside PAs. Moreover, displacement during day-night was significantly different for tigers inside and outside PAs. Similarly, wolf also showed significant difference between day-night movement. However, no difference in day-night movement was found for leopard and dholes. Anthropogenic factors such as road length and proportion of agriculture within the home range of tigers outside PAs were found to be significantly different. All the habitat variables in the home range showed significant difference between the social canids. The core area size for tiger outside PA and wolf was found greater than PAs. The study on movement of large carnivore species across landscapes is crucial for conservation planning. Our findings can be a starting point for interlinking animal movement and landscape management of large carnivore conservation in the current Anthropocene.

11.
Sci Rep ; 11(1): 2564, 2021 01 28.
Artículo en Inglés | MEDLINE | ID: mdl-33510319

RESUMEN

Eld's deer (Rucervus eldii) with three recognised subspecies (R. e. eldii, R. e. thamin, and R. e. siamensis) represents one of the most threatened cervids found in Southeast Asia. The species has experienced considerable range contractions and local extinctions owing to habitat loss and fragmentation, hunting, and illegal trade across its distribution range over the last century. Understanding the patterns of genetic variation is crucial for planning effective conservation strategies. This study investigated the phylogeography, divergence events and systematics of Eld's deer subspecies using the largest mtDNA dataset compiled to date. We also analysed the genetic structure and demographic history of R. e. eldii using 19 microsatellite markers. Our results showed that R. e. siamensis exhibits two divergent mtDNA lineages (mainland and Hainan Island), which diverged around 0.2 Mya (95% HPD 0.1-0.2), possibly driven by the fluctuating sea levels of the Early Holocene period. The divergence between R. e. eldii and R. e. siamensis occurred around 0.4 Mya (95% HPD 0.3-0.5), potentially associated with the adaptations to warm and humid climate with open grassland vegetation that predominated the region. Furthermore, R. e. eldii exhibits low levels of genetic diversity and small contemporary effective population size (median = 7, 4.7-10.8 at 95% CI) with widespread historical genetic bottlenecks which accentuates its vulnerability to inbreeding and extinction. Based on the observed significant evolutionary and systematic distance between Eld's deer and other species of the genus Rucervus, we propose to classify Eld's deer (Cervus eldii) in the genus Cervus, which is in congruent with previous phylogenetic studies. This study provides important conservation implications required to direct the ongoing population recovery programs and planning future conservation strategies.


Asunto(s)
Ciervos/genética , Genética de Población/métodos , Animales , Evolución Biológica , Ciervos/clasificación , Especies en Peligro de Extinción
12.
PLoS One ; 15(6): e0233569, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32497053

RESUMEN

Despite appreciable advances in carnivore ecology, studies on small cats remain limited with carnivore research in India being skewed towards large cats. Small cats are more specialized than their larger cousins in terms of resource selection. Studies on small cat population and habitat preference are critical to evaluate their status to ensure better management and conservation. We estimated abundance of two widespread small cats, the jungle cat, and the rusty-spotted cat, and investigated their habitat associations based on camera trap captures from a central Indian tiger reserve. We predicted fine-scale habitat segregation between these sympatric species as a driver of coexistence. We used an extension of the spatial count model in a Bayesian framework approach to estimate the population density of jungle cat and rusty-spotted cat and used generalized linear models to explore their habitat associations. Densities of rusty-spotted cat and jungle cat were estimated as 6.67 (95% CI 4.07-10.74) and 4.01 (95% CI 2.65-6.12) individuals/100 km2 respectively. Forest cover and evapotranspiration were positively associated with rusty-spotted cat occurrence whereas both factors had a significant negative relation with jungle cat occurrence. The results directed habitat segregation between these small cats with affinities of rusty-spotted cat and jungle cat towards well-forested and open scrubland areas respectively. Our estimates highlight the widespread applicability of this model for density estimation of species with no individual identification. Moreover, the study outcomes can aid in targeted management decisions and serve as the baseline for species conservation as these models allow robust population estimation of elusive species along with predicting their habitat preferences.


Asunto(s)
Felidae/fisiología , Bosques , Simpatría/fisiología , Animales , Teorema de Bayes , Gatos , Conservación de los Recursos Naturales , Ecología/métodos , India , Modelos Lineales , Movimiento/fisiología , Densidad de Población
13.
PeerJ ; 7: e7453, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31534835

RESUMEN

BACKGROUND: The Asiatic wild dog or dhole (Cuon alpinus) is a highly elusive, monophyletic, forest dwelling, social canid distributed across south and Southeast Asia. Severe pressures from habitat loss, prey depletion, disease, human persecution and interspecific competition resulted in global population decline in dholes. Despite a declining population trend, detailed information on population size, ecology, demography and genetics is lacking. Generating reliable information at landscape level for dholes is challenging due to their secretive behaviour and monomorphic physical features. Recent advances in non-invasive DNA-based tools can be used to monitor populations and individuals across large landscapes. In this paper, we describe standardization and validation of faecal DNA-based methods for individual identification of dholes. We tested this method on 249 field-collected dhole faeces from five protected areas of the central Indian landscape in the state of Maharashtra, India. RESULTS: We tested a total of 18 cross-species markers and developed a panel of 12 markers for unambiguous individual identification of dholes. This marker panel identified 101 unique individuals from faecal samples collected across our pilot field study area. These loci showed varied level of amplification success (57-88%), polymorphism (3-9 alleles), heterozygosity (0.23-0.63) and produced a cumulative misidentification rate or PID(unbiased) and PID(sibs) value of 4.7 × 10-10 and 1.5 × 10-4, respectively, indicating a high statistical power in individual discrimination from poor quality samples. CONCLUSION: Our results demonstrated that the selected panel of 12 microsatellite loci can conclusively identify dholes from poor quality, non-invasive biological samples and help in exploring various population parameters. This genetic approach would be useful in dhole population estimation across its range and will help in assessing population trends and other genetic parameters for this elusive, social carnivore.

14.
J Genet ; 98(2)2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31204725

RESUMEN

Burgeoning pressures of habitat loss is a major cause of herbivore decline across India, forcing them to coexist with humans in non-protected areas. Their conservation in such landscapes is challenging due to paucity of ecological and demographic information. The northern subspecies of swamp deer, Rucervus duvaucelii duvaucelii, is one such herbivore that lives across human dominated landscapes in Terai region and upper Gangetic plains of north India. Here, we describe species-specific molecular markers and a cervid-specific molecular sexing assay for swamp deer and four other coexisting cervids sambar, chital, barking deer and hog deer. Our markers show species-specific band patterns and a high success rate of 88.21% in large number of field collected referencesamples for all species. Faecal pellets from pilot swamp deer survey samples from upper Ganges basin show 93.81% success rate, and only 5.5% misidentification based on morphological characteristics. Our cervid-specific molecular sexing multiplex assay accurately ascertained 81.15% samples to respective sexes. These molecular approaches provide an easy, quick and cheap option to generate critical information on herbivore population parameters and aid their conservation in this mosaic of protected and non-protected grassland habitats.


Asunto(s)
Ciervos/clasificación , Ciervos/genética , Ecosistema , Genética de Población , Animales , Femenino , Geografía , Humanos , India , Masculino , Tipificación Molecular , Reacción en Cadena de la Polimerasa , Dinámica Poblacional , Especificidad de la Especie
15.
J Genet ; 97(5): 1457-1461, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30555094

RESUMEN

Asiatic wild dog (Cuon alpinus) or dhole is an endangered canid with fragmented distribution in South, East and Southeast Asia. The remaining populations of this species face severe conservation challenges from anthropogenic interventions, but only limited information is available at population and demography levels. Here, we describe the novel molecular approaches for unambiguous species and sex identification from noninvasively collected dhole samples. We successfully tested these assays on 130 field-collected dhole faecal samples from the Vidarbha part of central Indian tiger landscape that resulted in 97 and 77% successrates in species and sex identification, respectively. These accurate, fast and cheap molecular approaches prove the efficacy of such methods in gathering ecological data from this elusive, endangered canid and show their application in generating population level information from noninvasive samples.


Asunto(s)
Canidae/genética , ADN/genética , Especies en Peligro de Extinción , Heces/química , Animales , Canidae/clasificación , Conservación de los Recursos Naturales/métodos , Femenino , Masculino , Reproducibilidad de los Resultados , Análisis para Determinación del Sexo/métodos , Factores Sexuales , Especificidad de la Especie
16.
Mitochondrial DNA A DNA Mapp Seq Anal ; 29(8): 1276-1283, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-29540087

RESUMEN

Pangolins are a group of eight endangered mammalian species included in the family Manidae (Order Pholidota) and divided into four each African (Arboreal species; Phataginus tetradactyla, Phataginus tricuspis, Ground dwelling species; Smutsia gigantea and Smutsia temminckii) and Asian (Ground dwelling; Manis crassicaudata, Manis pentadactyla, Manis javanica and Manis culionensis) species. The taxonomy of all the eight extant pangolin species based on molecular genetics studies, remains unresolved and poorly examined. The present study is to address this lacuna by studying the phylogenetic, taxonomic status and molecular dating of Indian pangolin with other six out of eight extant pangolins (Sunda pangolin possibly extinct) based on complete coding region of mitochondrial cytochrome b gene. Overall sequences divergence among pangolins ranged between 0.01 ± 0.01 and 0.26 ± 0.03, where within 'Manis' it ranged between 0.01 ± 0.01 and 0.14 ± 0.03. Cytochrome b sequences based phylogenetic tree revealed, the division of seven pangolin species into two paraphyletic clades of African and Asian species, further these two paraphyletic clades were divided into three well-supported monophyletic clades, first for the genus 'Smutsia' with two African ground pangolins, second for the genus 'Phataginus' with two African arboreal pangolins and third for 'Manis' with three Asian species. Within clade of 'Manis', Chinese pangolin and Malayan pangolin are basal where Indian pangolin is present as a sister clade and furthermore, molecular dating analysis suggested that pangolins diverged from Carnivora at ∼87.2 MYA, followed by the split of Asian pangolins and African pangolins at ∼36.1 MYA and Indian pangolin split from Chinese pangolin and Malayan pangolin at ∼16.7 MYA.


Asunto(s)
Citocromos b/genética , Evolución Molecular , Filogenia , Xenarthra/genética , Animales , Xenarthra/clasificación
17.
Mitochondrial DNA B Resour ; 3(1): 245-249, 2018 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33474132

RESUMEN

Genetic analysis is an important tool in understanding population structure, genetic diversity, and phylogenetics of endangered species likely to be affected by microevolution and anthropogenic factors. Western Ghats landscape is one of the identified biodiversity hotspots in India, and micro-evolutionary processes are observed in this landscape due to the presence of the gaps in the mountain ranges. Nilgiri tahr is endemic to and distributed in this landscape while very little is known about genetic characteristics, population structure and impact of these gaps on the species. In the present study, two different populations of Nilgiri tahr from the north (NPG) and south (SPG) of Palghat gap (PG) were studied using the cytochrome b gene (Cyt b; 310 bp) of mtDNA genome in the Western Ghats, India. Two variable sites were observed in the Cyt b fragment while the mean pairwise genetic distance between these two populations was 0.007. All the samples phylogenetically clustered in either north or south of PG. The presence of shallow divergence indicates the presence of suitable habitat in past which may have facilitated movement between NPG and SPG. A subsequent change in Paleo-climatic conditions and gradual formation of PG may have resulted in population diversification during the Pleistocene. Besides, Forensically Informative Nucleotide Sequence (FINS) observed would help in geo-assigning any individual from NPG or SPG to understand the likely influences on population demography due to poaching.

18.
Mitochondrial DNA B Resour ; 3(1): 250-255, 2018 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-33474133

RESUMEN

DNA barcoding has become a popular method of choice for identification of specimen based on molecular techniques. Here, we present preliminary findings on generating robust DNA barcode library of Cervids of India. The dataset comprising the DNA barcode library of seven deer species included in the genus Cervus, Axis and Muntiacus classified under family Cervidae. Mitochondrial Cytochrome C Oxidase subunit I gene of ca. 710 bp accepted widely as DNA barcode region, was used for generating species specific signature from 31 known samples of seven Indian deer species. Expectedly, the NJ tree clustered three genera i.e. Cervus, Axis and Muntiacus of Cervids of India into three clades. Further, the intra- and interspecies distances based on Kimura 2 parameter model also supported the results. The average intra- and interspecies sequence divergence were 0.011 (±0.09) and 0.65 (±0.14), respectively. The present study has exhibited that DNA barcoding has discriminating power to delineate boundaries among the closely related species. The data generated are of high importance to the law enforcement agencies in effective identification of species in wildlife offence cases. The similar approach can be utilized for generating DNA barcodes for other Indian mammals for making effective management and conservation action decisions.

19.
Mitochondrial DNA B Resour ; 3(2): 640-644, 2018 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-33474269

RESUMEN

Pangolins are the world`s most trafficked mammalian species classified under family Manidae and face severe threat of extinction, largely due to the illicit trade of its parts and products, especially scales, in international markets. Pangolin scales are believed to be used in Traditional Chinese Medicines (TCM) and meat is used as delicacies in restaurants. Of the eight extant species of pangolin, morphological discrimination is easy but the situation becomes precarious once the scales and meat samples are seized and it is difficult to identify species based on morphology in such cases. However, wildlife DNA forensics has played an instrumental role in the identification of species from such type of materials. The present study investigated that three mitochondrial genes (Cyt b, 16S rRNA, and 12S rRNA) clearly showed the variation among seven extant pangolin species (Manis culionensis; possibly extinct), whereas, maximum variation was obtained in cytochrome b when compared to another two mitochondrial genes. The present study revealed that obtained SNPs based on short sequence length (Intervals) within the three mitochondrial genes will be helpful to design the short molecular marker and species-specific probe that is used in wildlife forensic for identifying pangolin species from the degraded sample. We also advocate using more than one molecular marker for species discrimination so as to minimize any false identification of the mammal's species reported in the trade. Furthermore, data generated from the study would help in strengthening the DNA database of Indian pangolin species.

20.
Sci Rep ; 7(1): 9614, 2017 08 29.
Artículo en Inglés | MEDLINE | ID: mdl-28851952

RESUMEN

Tigers have lost 93% of their historical range worldwide. India plays a vital role in the conservation of tigers since nearly 60% of all wild tigers are currently found here. However, as protected areas are small (<300 km2 on average), with only a few individuals in each, many of them may not be independently viable. It is thus important to identify and conserve genetically connected populations, as well as to maintain connectivity within them. We collected samples from wild tigers (Panthera tigris tigris) across India and used genome-wide SNPs to infer genetic connectivity. We genotyped 10,184 SNPs from 38 individuals across 17 protected areas and identified three genetically distinct clusters (corresponding to northwest, southern and central India). The northwest cluster was isolated with low variation and high relatedness. The geographically large central cluster included tigers from central, northeastern and northern India, and had the highest variation. Most genetic diversity (62%) was shared among clusters, while unique variation was highest in the central cluster (8.5%) and lowest in the northwestern one (2%). We did not detect signatures of differential selection or local adaptation. We highlight that the northwest population requires conservation attention to ensure persistence of these tigers.


Asunto(s)
Conservación de los Recursos Naturales , Especies en Peligro de Extinción , Genética de Población , Tigres/genética , Animales , Sitios Genéticos , Variación Genética , Genómica/métodos , Geografía , Secuenciación de Nucleótidos de Alto Rendimiento , India , Filogenia , Polimorfismo de Nucleótido Simple , Selección Genética , Tigres/clasificación
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