Publications by authors named "Robyn Cowan"

Article Synopsis
  • Angiosperms are vital for ecosystems and human life, making it important to understand their evolutionary history to grasp their ecological dominance.
  • The study builds an extensive tree of life for about 8,000 angiosperm genera using 353 nuclear genes, significantly increasing the sampling size and refining earlier classifications.
  • The findings reveal a complex evolutionary history marked by high gene tree conflict and rapid diversification, particularly during the early angiosperm evolution, with shifts in diversification rates linked to global temperature changes.
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Premise: The genetic structure of hybrid zones provides insight into the potential for gene flow to occur between plant taxa. Four closely related European orchid species (Orchis anthropophora, O. militaris, O.

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Premise: To further advance the understanding of the species-rich, economically and ecologically important angiosperm order Myrtales in the rosid clade, comprising nine families, approximately 400 genera and almost 14,000 species occurring on all continents (except Antarctica), we tested the Angiosperms353 probe kit.

Methods: We combined high-throughput sequencing and target enrichment with the Angiosperms353 probe kit to evaluate a sample of 485 species across 305 genera (76% of all genera in the order).

Results: Results provide the most comprehensive phylogenetic hypothesis for the order to date.

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Premise: The inference of evolutionary relationships in the species-rich family Orchidaceae has hitherto relied heavily on plastid DNA sequences and limited taxon sampling. Previous studies have provided a robust plastid phylogenetic framework, which was used to classify orchids and investigate the drivers of orchid diversification. However, the extent to which phylogenetic inference based on the plastid genome is congruent with the nuclear genome has been only poorly assessed.

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Article Synopsis
  • The tree of life serves as a biological map for understanding evolution and the characteristics of life on Earth, particularly focusing on flowering plants (angiosperms) which have many data gaps despite their importance.
  • The article presents a phylogenomic platform utilizing high-throughput sequencing tools and 353 nuclear genes to deepen the exploration of the angiosperm tree of life, with methods, data release, and an open data portal called the Kew Tree of Life Explorer.
  • The first data release includes the largest nuclear phylogenomic dataset for angiosperms to date, covering a vast number of samples and families, and provides a "first pass" tree that supports current taxonomy while questioning previously established relationships among plant orders.
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Article Synopsis
  • Plastid sequences have often been used for phylogenetic analysis without rigorous testing of their accuracy, particularly in the diverse bee orchid genus Ophrys, highlighting potential issues with relying on these sequences for understanding species evolution.
  • Combining morphometric data from 124 plants and whole-plastome sequencing from 71 plants, the study challenges established species classifications, showing that neither morphological nor molecular distinctions are clear below the macrospecies level.
  • The findings suggest that plastid data may better reflect geographic factors rather than actual species differences, indicating a dynamic and interconnected evolutionary network rather than the traditional view of separate, distinct species.
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Nepenthaceae is one of the largest carnivorous plant families and features ecological and morphological adaptations indicating an impressive adaptive radiation. However, investigation of evolutionary and taxonomic questions is hindered by poor phylogenetic understanding, with previous molecular studies based on limited loci and taxa. We use high-throughput sequencing with a target-capture methodology based on a 353-loci, probe set to recover sequences for 197 samples, representing 151 described or putative Nepenthes species.

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The world's herbaria collectively house millions of diverse plant specimens, including endangered or extinct species and type specimens. Unlocking genetic data from the typically highly degraded DNA obtained from herbarium specimens was difficult until the arrival of high-throughput sequencing approaches, which can be applied to low quantities of severely fragmented DNA. Target enrichment involves using short molecular probes that hybridise and capture genomic regions of interest for high-throughput sequencing.

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Population loss due to habitat disturbance is a major concern in biodiversity conservation. Here we investigate the genetic causes of the demographic decline observed in English populations of Pulsatilla vulgaris and the consequences for conservation. Using 10 nuclear microsatellite markers, we compare genetic variation in wild populations with restored and seed-regenerated populations (674 samples).

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Sequencing of target-enriched libraries is an efficient and cost-effective method for obtaining DNA sequence data from hundreds of nuclear loci for phylogeny reconstruction. Much of the cost of developing targeted sequencing approaches is associated with the generation of preliminary data needed for the identification of orthologous loci for probe design. In plants, identifying orthologous loci has proven difficult due to a large number of whole-genome duplication events, especially in the angiosperms (flowering plants).

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Floral foraging resources are valuable for pollinator conservation on farmland, and their provision is encouraged by agri-environment schemes in many countries. Across Europe, wildflower seed mixtures are widely sown on farmland to encourage pollinators, but the extent to which key pollinator groups such as solitary bees exploit and benefit from these resources is unclear. We used high-throughput sequencing of 164 pollen samples extracted from the brood cells of six common cavity-nesting solitary bee species (, , , , and ) which are widely distributed across the UK and Europe.

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Premise Of The Study: Southwestern Britain is an emblematic hotspot of polyploid diversity of whitebeams ( agg.; Rosaceae) with ca. 30 polyploid endemic species.

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The radiation of the genus Cheirolophus (Asteraceae) in Macaronesia constitutes a spectacular case of rapid diversification on oceanic islands. Twenty species - nine of them included in the IUCN Red List of Threatened Species - have been described to date inhabiting the Madeiran and Canarian archipelagos. A previous phylogenetic study revealed that the diversification of Cheirolophus in Macaronesia started less than 2 Ma.

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Herbarium collections are potentially an enormous resource for DNA studies, but the use of herbarium specimens in molecular studies has thus far been slowed down by difficulty in obtaining amplifiable DNA. Here we compare a set of commercially available DNA extraction protocols and their performance in terms of DNA purity and yield, and PCR amplification success as measured by using three differentially sized markers, the rbcL barcoding marker (cpDNA), the LEAFY exon 3 (nrDNA), and the trnL((UAA)) P6 loop (cpDNA). Results reveal large differences between extraction methods, where DNA purity rather than yield is shown to be strongly correlated with PCR success.

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DNA barcoding, using a short gene sequence from a standardized region of the genome, is a species identification tool which would not only aid species discovery but would also have applications ranging from large-scale biodiversity surveys through to identification of a single fragment of material in forensic contexts. To fulfill this vision a universal, relatively cheap, scalable system needs to be in place. The mitochondrial locus being used for many animal groups and algae is not suitable for use in land plants, and an appropriate alternative is needed.

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There has been considerable debate, but little consensus regarding locus choice for DNA barcoding land plants. This is partly attributable to a shortage of comparable data from all proposed candidate loci on a common set of samples. In this study, we evaluated the seven main candidate plastid regions (rpoC1, rpoB, rbcL, matK, trnH-psbA, atpF-atpH, psbK-psbI) in three divergent groups of land plants [Inga (angiosperm); Araucaria (gymnosperm); Asterella s.

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An international consortium of major natural history museums, herbaria and other organizations has launched an ambitious project, the 'Barcode of Life Initiative', to promote a process enabling the rapid and inexpensive identification of the estimated 10 million species on Earth. DNA barcoding is a diagnostic technique in which short DNA sequence(s) can be used for species identification. The first international scientific conference on Barcoding of Life was held at the Natural History Museum in London in February 2005, and here we review the scientific challenges discussed during this conference and in previous publications.

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Background And Aims: Nuclear DNA content (C-value) varies approximately 1000-fold across the angiosperms, and this variation has been reported to have an effect on the quality of AFLP fingerprints. Various methods have been proposed for circumventing the problems associated with small and large genomes. Here we investigate the range of nuclear DNA contents across which the standard AFLP protocol can be used.

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