Publications by authors named "Ellie Armstrong"

Despite substantial reductions in the cost of sequencing over the last decade, genetic panels remain relevant due to their cost-effectiveness and flexibility across a variety of sample types. In particular, single nucleotide polymorphism (SNP) panels are increasingly favoured for conservation applications. SNP panels are often used because of their adaptability, effectiveness with low-quality samples, and cost-efficiency for population monitoring and forensics.

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  • Scientists are studying the DNA of tigers to understand their genetic diversity and help protect them, especially since many tigers in the wild are endangered.
  • This research looks at tigers that are kept in captivity, like privately owned ones in the U.S., known as "Generic" tigers, which might have mixed ancestry from different tiger types.
  • The study found that these Generic tigers have similar genetic diversity to wild tigers and can help conservation efforts by creating a new way to identify tiger ancestry using less expensive genetic testing methods.
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Reference genome assemblies have been created from multiple lineages within the Canidae family; however, despite its phylogenetic relevance as a basal genus within the clade, there is currently no reference genome for the gray fox (Urocyon cinereoargenteus). Here, we present a chromosome-level assembly for the gray fox (U. cinereoargenteus), which represents the most contiguous, non-domestic canid reference genome available to date, with 90% of the genome contained in just 34 scaffolds and a contig N50 and scaffold N50 of 59.

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Environmental change is intensifying the biodiversity crisis and threatening species across the tree of life. Conservation genomics can help inform conservation actions and slow biodiversity loss. However, more training, appropriate use of novel genomic methods and communication with managers are needed.

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  • * A study focused on Scaptomyza, a genus related to Drosophila, found that herbivorous species have fewer chemosensory and detoxification genes compared to nonherbivorous species, with higher rates of gene turnover in certain families.
  • * The most affected genes are related to detecting plant toxins and compounds from their ancestral diet, shedding light on the genetic basis of herbivory and identifying gene candidates relevant to dietary changes in Drosophila. *
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We provide novel genomic resources to help understand the genomic traits involved in elephant health and to aid conservation efforts. We sequence 11 elephant genomes (5 African savannah, 6 Asian) from North American zoos, including 9 de novo assemblies. We estimate elephant germline mutation rates and reconstruct demographic histories.

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Herbivorous insects are exceptionally diverse, accounting for a quarter of all known eukaryotic species, but the genetic basis of adaptations that enabled this dietary transition remains poorly understood. Many studies have suggested that expansions and contractions of chemosensory and detoxification gene families - genes directly mediating interactions with plant chemical defenses - underlie successful plant colonization. However, this hypothesis has been challenging to test because the origins of herbivory in many lineages are ancient (>150 million years ago [mya]), obscuring genomic evolutionary patterns.

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Summary: Here, we introduce RatesTools, an automated pipeline to infer de novo mutation rates from parent-offspring trio data of diploid organisms. By providing a reference genome and high-coverage, whole-genome resequencing data of a minimum of three individuals (sire, dam and offspring), RatesTools provides a list of candidate de novo mutations and calculates a putative mutation rate. RatesTools uses several quality filtering steps, such as discarding sites with low mappability and highly repetitive regions, as well as sites with low genotype and mapping qualities to find potential de novo mutations.

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  • The genus Panthera includes popular big cats like tigers, snow leopards, and African leopards, but there are limited reference genomes available for high-resolution studies.
  • Researchers assembled chromosome-level genomes for these three species using advanced sequencing techniques, including both short- and long-read technologies, as well as Hi-C data for better accuracy.
  • The goal of this research is to enhance understanding and conservation efforts for these iconic mammals through improved genomic resources.
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The brown bear (Ursus arctos) is the second largest and most widespread extant terrestrial carnivore on Earth and has recently emerged as a medical model for human metabolic diseases. Here, we report a fully phased chromosome-level assembly of a male North American brown bear built by combining Pacific Biosciences (PacBio) HiFi data and publicly available Hi-C data. The final genome size is 2.

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Hibernation in brown bears is an annual process involving multiple physiologically distinct seasons-hibernation, active, and hyperphagia. While recent studies have characterized broad patterns of differential gene regulation and isoform usage between hibernation and active seasons, patterns of gene and isoform expression during hyperphagia remain relatively poorly understood. The hyperphagia stage occurs between active and hibernation seasons and involves the accumulation of large fat reserves in preparation for hibernation.

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  • Recent studies have focused on estimating germline mutation rates in humans and nonhuman species using large family pedigrees, but differences in methods make comparisons challenging.
  • The text outlines the various steps involved in estimating these mutation rates, including sampling and sequencing, while highlighting the different methods and choices made in recent research.
  • A competition among five labs showed nearly double variation in estimated mutation rates for rhesus macaques, underlining the importance of standardized methods for future mutation rate studies.
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The diversification of a host lineage can be influenced by both the external environment and its assemblage of microbes. Here, we use a young lineage of spiders, distributed along a chronologically arranged series of volcanic mountains, to investigate how their associated microbial communities have changed as the spiders colonized new locations. Using the stick spider Ariamnes waikula (Araneae, Theridiidae) on the island of Hawai'i, and outgroup taxa on older islands, we tested whether each component of the "holobiont" (spider hosts, intracellular endosymbionts and gut microbial communities) showed correlated signatures of diversity due to sequential colonization from older to younger volcanoes.

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Spiders (Araneae) have a diverse spectrum of morphologies, behaviors, and physiologies. Attempts to understand the genomic-basis of this diversity are often hindered by their large, heterozygous, and AT-rich genomes with high repeat content resulting in highly fragmented, poor-quality assemblies. As a result, the key attributes of spider genomes, including gene family evolution, repeat content, and gene function, remain poorly understood.

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Genome-scale sequence data have invigorated the study of hybridization and introgression, particularly in animals. However, outside of a few notable cases, we lack systematic tests for introgression at a larger phylogenetic scale across entire clades. Here, we leverage 155 genome assemblies from 149 species to generate a fossil-calibrated phylogeny and conduct multilocus tests for introgression across 9 monophyletic radiations within the genus Drosophila.

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The unprecedented rate of extinction calls for efficient use of genetics to help conserve biodiversity. Several recent genomic and simulation-based studies have argued that the field of conservation biology has placed too much focus on conserving genome-wide genetic variation, and that the field should instead focus on managing the subset of functional genetic variation that is thought to affect fitness. Here, we critically evaluate the feasibility and likely benefits of this approach in conservation.

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Genomic diversity and past population histories are key considerations in the fields of conservation and evolutionary biology. In this issue of Molecular Ecology Resources, Prasad et al. (Mol.

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Over 100 years of studies in and related species in the genus have facilitated key discoveries in genetics, genomics, and evolution. While high-quality genome assemblies exist for several species in this group, they only encompass a small fraction of the genus. Recent advances in long-read sequencing allow high-quality genome assemblies for tens or even hundreds of species to be efficiently generated.

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Species conservation can be improved by knowledge of evolutionary and genetic history. Tigers are among the most charismatic of endangered species and garner significant conservation attention. However, their evolutionary history and genomic variation remain poorly known, especially for Indian tigers.

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Background: The lion (Panthera leo) is one of the most popular and iconic feline species on the planet, yet in spite of its popularity, the last century has seen massive declines for lion populations worldwide. Genomic resources for endangered species represent an important way forward for the field of conservation, enabling high-resolution studies of demography, disease, and population dynamics. Here, we present a chromosome-level assembly from a captive African lion from the Exotic Feline Rescue Center (Center Point, IN) as a resource for current and subsequent genetic work of the sole social species of the Panthera clade.

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  • Horizontal gene transfer has significantly impacted microbial evolution, and this study explores its role in animals, specifically vinegar flies and aphids.
  • The research identifies the transfer of the cdtB gene, associated with bacterial toxins, into the genomes of these insects, linking these genes to bacteriophage that affect symbiotic bacteria in aphids.
  • Findings suggest that cdtB is actively expressed during vulnerable life stages in these insects and may provide a defense mechanism against natural predators.
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The diverse array of phenotypes and courtship displays exhibited by birds-of-paradise have long fascinated scientists and nonscientists alike. Remarkably, almost nothing is known about the genomics of this iconic radiation. There are 41 species in 16 genera currently recognized within the birds-of-paradise family (Paradisaeidae), most of which are endemic to the island of New Guinea.

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  • A high-quality reference genome is crucial for studying endangered species like the African wild dog, providing insights into their population dynamics and aiding conservation efforts.
  • Researchers successfully created a cost-effective reference genome for the African wild dog, achieving significant genomic continuity and reconstructing a large portion of conserved mammalian genes.
  • The study indicates that African wild dogs possess high genetic diversity despite historically low population sizes, underscoring the potential for improved genetic monitoring and conservation strategies for this species.
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We report here the draft genome assembly, transcriptome assembly, and annotation of the lichen-forming fungus (Pers.) Ach., the type species for Arthoniomycetes, a class of lichen-forming, lichenicolous, and saprobic Ascomycota.

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