20 research outputs found
Worldwide Diaspora of Aethina tumida (Coleoptera: Nitidulidae), a Nest Parasite of Honey Bees
Native to sub-Saharan Africa, Aethina tumida Murray (Coleoptera: Nitidulidae) is now an invasive pest of honey bee, Apis mellifera L., colonies in Australia and North America. Knowledge about the introduction(s) of this beetle from Africa into and among the current ranges will elucidate pest populations and invasion pathways and contribute to knowledge of how a parasite expands in new populations. We examined genetic variation in adult beetle samples from the United States, Australia, Canada, and Africa by sequencing a 912-base pair region of the mitochondrial DNA cytochrome c oxidase subunit I gene and screening 10 informative microsatellite loci. One Canadian introduction of small hive beetles can be traced to Australia, whereas the second introduction seems to have come from the United States. Beetles now resident in Australia were of a different African origin than were beetles in North America. North American beetles did not show covariance between two mitochondrial haplotypes and their microsatellite frequencies, suggesting that these beetles have a shared source despite having initial genetic structure within their introduced range. Excellent dispersal of beetles, aided in some cases by migratory beekeeping and the bee trade, seems to lead to panmixis in the introduced populations as well as in Afric
Conservation status of buff-breasted sandpipers (Tryngites subruficollis) in the Western Hemisphere: a conservation genetic approach
Master of ScienceDivision of BiologySamantha M. WiselyRange-wide estimates of shorebird (Aves: Charadriiformes) populations suggest sharp declines in population sizes across a range of species. Efforts to accurately assess the conservation status of wild populations are becoming increasingly vital to species management. One shorebird of conservation concern, the Buff-breasted Sandpiper (Tryngites subruficollis), is a New World migrant which winters in southeastern South America and breeds in the arctic. To establish an updated conservation status for Buff-breasted Sandpipers, we conducted a molecular survey of wild populations on spatial and temporal scales. We analyzed patterns of global population structure, demographic trends, and phylogeography using nine polymorphic microsatellites and two mitochondrial DNA (mtDNA) markers, cytochrome b and the control region, among 477 individuals across their distributional range. To empirically assess the impact of population declines on genetic diversity, we also surveyed segments of the same two mtDNA markers from 220 museum specimens collected across a 135-year period. Contemporary microsatellite and mtDNA analyses revealed that Buff-breasted Sandpipers are admixed on a global scale, with effective population size estimates ranging from 2,657 to 16,400 birds and no signal of a recent genetic bottleneck. Contemporary mtDNA analyses suggested a pattern of haplotype diversity consistent with a historic radiation from a single refugium which we estimated to have occurred between 8,000−45,000 years before present. Using five measures of mtDNA diversity (haplotype and nucleotide diversity, trend analyses of haplotype richness, Watterson’s estimate of theta, and phi-statistics), as well as a Bayesian Skyline reconstruction of demographic trends in effective population size (N[subscript]e[subscript]f), we concluded that substantial mtDNA diversity and N[subscript]e[subscript]f had not been lost as a result of the population declines in this species. While genetic diversity did not appear to have been lost due to population losses, management efforts must focus on preventing future losses in order for wild populations to remain viable. Our results suggested that the global population of Buff-breasted Sandpipers should be treated as a single, panmictic conservation unit and that successful management must focus on preventing further declines and habitat fragmentation
Data from: Nuclear genetic analysis of the red fox across its trans-Pacific range
The red fox (Vulpes vulpes) occurs on multiple continents in diverse habitats, making it an informative system for evolutionary genomic research. However, its phylogeography remains unclear. Previously, mitochondrial DNA and small numbers of nuclear loci provided discordant views. Both markers indicated deep divergence (~ 0.5 MY) between Eurasian and southern North American populations but differed in the apparent continental affinity of Alaskan red foxes, implying some degree of gene exchange during secondary contact (~0.1 MY). We assayed >173,000 nuclear genomic sites in 52 red foxes, along with 2 Rueppell’s (V. rueppellii) foxes and a gray wolf (Canis lupus) using the Illumina CanineHD BeadChip. We obtained 5,107 SNPs that were polymorphic in the foxes. Consistent with the Afro-Eurasian origins of red foxes, genetic diversity was higher in Eurasian than North American samples. Phylogenetic trees indicated that Alaskan and southern North American red foxes formed a monophyletic group nested within the Eurasian clade. However, admixture models suggested Alaskan red foxes contained up to 40% Eurasian ancestry. We hypothesize that North American red foxes either hybridized with Eurasian foxes in Beringia at the start of the last glaciation or merged with a Beringian population after the last glaciation. Future work is needed to test between these scenarios and assess speciation
Identification of 12 EST-derived SSR markers in Lumbricus rubellus
While many species of earthworms are globally distributed, very little is known about the genetic population dynamics of this diverse group. We present the characterization of novel simple sequence repeat (SSR) markers, including primer information, number of alleles, repeat motif, and approximate size ranges, to be used in population genetic analyses of the earthworm Lumbricus rubellus Hoffmeister 1843. Specifically, we designed and characterized 12 novel, polymorphic markers derived from published expressed sequence tags (EST) for amplification in L. rubellus. The mean number of alleles per locus was 6.25 ± 1.91, indicating these markers will be sufficiently polymorphic for population genetic studies of this species
Draft genome of tule elk Cervus canadensis nannodes [version 2; referees: 2 approved]
This paper presents the first draft genome of the tule elk (Cervus elaphus nannodes), a subspecies native to California that underwent an extreme genetic bottleneck in the late 1800s. Â The genome was generated from Illumina HiSeq 3000 whole genome sequencing of four individuals, resulting in the assembly of 2.395 billion base pairs (Gbp) over 602,862 contigs over 500 bp and N50 = 6,885 bp. This genome provides a resource to facilitate future genomic research on elk and other cervids
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Draft genome of tule elk Cervus canadensis nannodes.
This paper presents the first draft genome of the tule elk ( Cervus elaphus nannodes), a subspecies native to California that underwent an extreme genetic bottleneck in the late 1800s. The genome was generated from Illumina HiSeq 3000 whole genome sequencing of four individuals, resulting in the assembly of 2.395 billion base pairs (Gbp) over 602,862 contigs over 500 bp and N50 = 6,885 bp. This genome provides a resource to facilitate future genomic research on elk and other cervids
Metadata and genotypes for tule elk and contigs containing microsatellites
Metadata and genotypes for tule elk and contigs containing microsatellite
Data from: Development and characterization of 15 polymorphic di-nucleotide microsatellite markers for tule elk using HiSeq3000
The tule elk (Cervus elaphus nannodes) experienced a severe bottleneck in the 1800s, resulting in low genetic diversity. There is a need for high-resolution genetic assays that can be used to differentiate individual elk, including close relatives, with high confidence. An efficient assay requires multiple markers both polymorphic and that can be amplified in concert with other markers in multiplex reactions. To develop such markers, we employed 150-bp paired-end whole genome shotgun sequencing on an Illumina HiSeq3000 platform to discover dinucleotide microsatellite markers. After preliminary screening of these markers, we selected and screened 15 candidate loci and 5 existing tetra nucleotide markers in 56 tule elk. We combined these markers in 2 multiplex reactions and report primer concentrations and PCR conditions enabling their efficient amplification
Worldwide Diaspora of Aethina tumida (Coleoptera: Nitidulidae), a Nest Parasite of Honey Bees
Native to sub-Saharan Africa, Aethina tumida Murray (Coleoptera: Nitidulidae) is now an invasive pest of honey bee, Apis mellifera L., colonies in Australia and North America. Knowledge about the introduction (s) of this beetle from Africa into and among the current ranges will elucidate pest populations and invasion pathways and contribute to knowledge of how a parasite expands in new populations. We examined genetic variation in adult beetle samples from the United States, Australia, Canada, and Africa by sequencing a 912-base pair region of the mitochondrial DNA cytochrome c oxidase subunit I gene and screening 10 informative microsatellite loci. One Canadian introduction of small hive beetles can be traced to Australia, whereas the second introduction seems to have come from the United States. Beetles now resident in Australia were of a different African origin than were beetles in North America. North American beetles did not show covariance between two mitochondrial haplotypes and their microsatellite frequencies, suggesting that these beetles have a shared source despite having initial genetic structure within their introduced range. Excellent dispersal of beetles, aided in some cases by migratory beekeeping and the bee trade, seems to lead to panmixis in the introduced populations as well as in Africa