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K L, V.

Publications and source records attributed to K L, V..

3 recordsLinked to original sources

Genome assemblies for seven families of birds from the Global South

Tropical regions are biodiversity-rich, yet remain underrepresented in the availability of genomic resources, as is evident in the Western Ghats of India, a biodiversity hotspot with high endemism. Here, we present high-quality, de novo genome assemblies for seven birds, representing seven families distributed in the Western Ghats: Black-naped Monarch (Monarchidae: Hypothymis azurea), Indian Yellow Tit (Paridae: Machlolophus aplonotus), Brown-cheeked Fulvetta (Leiothrichidae: Alcippe poioicephala), Malabar Trogon (Trogonidae: Harpactes fasciatus), Blue-bearded Bee-eater (Meropidae: Nyctyornis athertoni), Malabar Whistling-Thrush (Muscicapidae: Myophonus horsfieldii), Orange-headed Thrush (Turdidae: Geokichla citrina). Using a hybrid Oxford Nanopore long reads - Illumina short reads approach, we assembled genomes with sizes ranging from 1.03 to 1.13 Gbp. All assemblies demonstrated high contiguity and completeness (BUSCO scores >97%, UCEs >4799). Repeat masking identified [~]10% of the genomes as interspersed repeats, and functional annotations yielded an average of 9,619 protein-coding genes per species. Comparative analysis showed our assemblies had significantly higher contiguity than the median of existing avian genomes on NCBI (Wilcoxson test, p = 0.00226). Our genome assemblies fill a key geographic and taxonomic gap in the genomic data and provide a foundational resource for evolutionary and ecological research in the Old-World tropics.

genomics↗

High-quality genome assembly of the endemic threatened White-bellied Sholakili Sholicola albiventris (Muscicapidae: Blanford, 1868) from the Shola Sky Islands, India.

The White-bellied Sholakili (Sholicola albiventris) is an endemic, elevational restricted species occurring in the Shola Sky Islands of the Western Ghats of India. This unique understory bird, with a complex vocal repertoire, exhibits impacts of gene flow due to anthropogenic habitat fragmentation. Here, we present the first genome assembly for Sholicola albiventris, which was assembled using a combination of Nanopore and Illumina sequences. The final assembly is 1.083 Gbp, consisting of 975 scaffolds with an N50 of 68.64Mbp and L50 of 6. Our genome assemblys completeness is supported by a high number of BUSCOs (99.9%) and a total of 4887 ultraconserved element (UCE) loci retrieved. We also report the complete mitochondrial genome comprising 13 protein-coding genes, 22 tRNAs, and 2 rRNAs. We identified 11.82% of the nuclear genome as repetitive and 36,000 putative genes, with 12017 genes functionally annotated. Our assembly showed a great synteny between Taeniopygia guttata and Gallus gallus chromosome level assemblies. This reference will be pivotal for investigating landscape connectivity, sub-population genetics, local adaptation, and conservation genetics of this high-elevation, range-restricted endemic bird species.

genomics↗

Re-assessing the phylogenetic status and evolutionary relationship of Forest Owlet using genomic data

Phylogenetic relationships are often challenging to resolve in recent/younger lineage when only a few loci are used. Ultra Conserved Elements (UCE) are highly conserved regions across taxa that help resolve shallow and deep divergences. We utilized UCEs harvested from whole genomes to assess the phylogenetic position and taxonomic affiliation of an endangered endemic owlet in the family Strigidae - the Forest Owlet Athene blewitti. The taxonomic placement of this species has been revised multiple times. A multigene study attempted to address the question but showed a discrepancy across datasets in its placement of the species within genus Athene. We assembled a dataset of 5018 nuclear UCE loci with increased taxon sampling. Forest Owlet was found to be an early split from the Athene clade but sister to other Athene; and consistent across three approaches - maximum likelihood, bayesian, and the multispecies coalescence. Divergence dating using fossil calibrations suggest that the Athene lineage split from its ancestor about 7.6Mya, and the Forest Owlet diverged about 5.2Mya, consistent with previous multigene approaches. Despite osteological differences from other Athene, we suggest the placement of the Forest Owlet as a member of the Athene to emphasize its evolutionary relationship. Graphical Abstract O_FIG_DISPLAY_L [Figure 1] M_FIG_DISPLAY C_FIG_DISPLAY HIGHLIGHTSO_LIPhylogenomics using genome-wide nuclear markers yielded a well-supported topology for Athene and Glaucidium lineages. C_LIO_LIThree different methods of phylogenetic tree construction showed that Forest Owlet is an early split from all other Athene species. C_LIO_LIDivergence dating in the bayesian framework puts the Forest Owlet age between 5.0my to 5.5my. C_LI

evolutionary biology↗