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Robert D. Ward

Bio: Robert D. Ward is an academic researcher from CSIRO Marine and Atmospheric Research. The author has contributed to research in topics: Population & DNA barcoding. The author has an hindex of 45, co-authored 134 publications receiving 11102 citations. Previous affiliations of Robert D. Ward include Commonwealth Scientific and Industrial Research Organisation & Loughborough University.


Papers
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Journal ArticleDOI
TL;DR: It is concluded that cox1 sequencing, or ‘barcoding’, can be used to identify fish species.
Abstract: GC than sharks (44.7% versus 41.0%), again largely due to higher GC in the 3rd codon position in the former (36.3% versus 26.8%). Average within-species, genus, family, order and class Kimura two parameter (K2P) distances were 0.39%, 9.93%, 15.46%, 22.18% and 23.27%, respectively. All species could be differentiated by their cox1 sequence, although single individuals of each of two species had haplotypes characteristic of a congener. Although DNA barcoding aims to develop species identification systems, some phylogenetic signal was apparent in the data. In the neighbourjoining tree for all 754 sequences, four major clusters were apparent: chimaerids, rays, sharks and teleosts. Species within genera invariably clustered, and generally so did genera within families. Three taxonomic groups—dogfishes of the genus Squalus, flatheads of the family Platycephalidae, and tunas of the genus Thunnus—were examined more closely. The clades revealed after bootstrapping generally corresponded well with expectations. Individuals from operational taxonomic units designated as Squalus species B through F formed individual clades, supporting morphological evidence for each of these being separate species. We conclude that cox1 sequencing, or ‘barcoding’, can be used to identify fish species.

3,212 citations

Journal ArticleDOI
TL;DR: Electrophoretic data were analysed from 49 species of freshwater fish, 57 species of marine fish, and seven anadromous species to show reduced values of Hs in freshwater species are likely to reflect reduced effective subpopulation sizes relative to marine species.
Abstract: Electrophoretic data were analysed from 49 species of freshwater fish, 57 species of marine fish, and seven anadromous species. For each species, at least 15 individuals had been assayed for at least 15 loci in two or more subpopulations. The results showed that while average total heterozygosity (HT) was approximately equal in freshwater and marine species (0·062 and 0·064 respectively), subpopulation heterozygosity (Hs) was significantly less in the former group (0·046 and 0·059 respectively). Consequently the average degree of genetic subpopulation differentiation (HST) was significantly greater for freshwater species (0·222 v. 0·062). On average, it is likely that marine subpopulations exchange between 10 and 100 times more migrants per generation than freshwater subpopulations, presumably because of the relative absence of barriers to dispersal in the marine environment. The reduced values of Hs in freshwater species are likely to reflect reduced effective subpopulation sizes relative to marine species. The few andromous species that have been analysed show intermediate levels of GST.

981 citations

Journal ArticleDOI
TL;DR: Analysis is targeting a 648 base pair region of the mitochondrial cytochrome c oxidase I (COI) gene, targeting several specimens with divergent barcode sequences confirmed by integrative taxonomic analysis as new species.
Abstract: FISH-BOL, the Fish Barcode of Life campaign, is an international research collaboration that is assembling a standardized reference DNA sequence library for all fishes. Analysis is targeting a 648 base pair region of the mitochondrial cytochrome c oxidase I (COI) gene. More than 5000 species have already been DNA barcoded, with an average of five specimens per species, typically vouchers with authoritative identifications. The barcode sequence from any fish, fillet, fin, egg or larva can be matched against these reference sequences using BOLD; the Barcode of Life Data System (http://www.barcodinglife.org). The benefits of barcoding fishes include facilitating species identification, highlighting cases of range expansion for known species, flagging previously overlooked species and enabling identifications where traditional methods cannot be applied. Results thus far indicate that barcodes separate c. 98 and 93% of already described marine and freshwater fish species, respectively. Several specimens with divergent barcode sequences have been confirmed by integrative taxonomic analysis as new species. Past concerns in relation to the use of fish barcoding for species discrimination are discussed. These include hybridization, recent radiations, regional differentiation in barcode sequences and nuclear copies of the barcode region. However, current results indicate these issues are of little concern for the great majority of specimens.

805 citations

Journal ArticleDOI
TL;DR: A precipitous drop in costs and increase in sequencing efficiency is anticipated, with concomitant development of improved annotation technology, and it is proposed to create a collection of tissue and DNA specimens for 10,000 vertebrate species specifically designated for whole-genome sequencing in the very near future.
Abstract: American Genetic Association, Gordon and Betty Moore Foundation, NHGRI Intramural Sequencing Center, and UCSC Alumni Association to cost of the Genome 10K workshop; Howard Hughes Medical Institute to D. H.; Gordon and Betty Moore Foundation to S. C. S.; A

545 citations

Journal ArticleDOI
TL;DR: It is concluded that cox1 barcoding can be used to identify shark and ray species with a very high degree of accuracy and also highlights some taxonomic issues that need to be investigated further.
Abstract: DNA barcoding – sequencing a region of the mitochondrial cytochrome c oxidase 1 gene (cox1) – promises a rapid and accurate means of species identification, and of any life history stage. For sharks and rays, it may offer a ready means of identifying legal or illegal shark catches, including shark fins taken for the profitable shark fin market. Here it is shown that an analysis of sequence variability in a 655 bp region of cox1 from 945 specimens of 210 chondrichthyan species from 36 families permits the discrimination of 99.0% of these species. Only the two stingarees Urolophus sufflavus and U. cruciatus could not be separated, although these could be readily distinguished from eight other congeners. The average Kimura 2 parameter distance separating individuals within species was 0.37%, and the average distance separating species within genera was 7.48%. Two specimens that clustered with congeners rather than with their identified species-cluster were noted: these could represent instances of hybridisation (although this has not be documented for chondrichthyans), misidentification or mislabelling. It is concluded that cox1 barcoding can be used to identify shark and ray species with a very high degree of accuracy. The sequence variability characteristics of individuals of five species (Aetomylaeus nichofii, Dasyatis kuhlii, Dasyatis leylandi, Himantura gerrardi and Orectolobus maculatus) were consistent with cryptic speciation, and it is suggested that these five taxa be subjected to detailed taxonomic examination to confirm or refute this suggestion. The present barcoding study holds out great hope for the ready identification of sharks, shark products and shark fins, and also highlights some taxonomic issues that need to be investigated further.

297 citations


Cited by
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Journal ArticleDOI
TL;DR: Primer3’s current capabilities are described, including more accurate thermodynamic models in the primer design process, both to improve melting temperature prediction and to reduce the likelihood that primers will form hairpins or dimers.
Abstract: Polymerase chain reaction (PCR) is a basic molecular biology technique with a multiplicity of uses, including deoxyribonucleic acid cloning and sequencing, functional analysis of genes, diagnosis of diseases, genotyping and discovery of genetic variants. Reliable primer design is crucial for successful PCR, and for over a decade, the open-source Primer3 software has been widely used for primer design, often in high-throughput genomics applications. It has also been incorporated into numerous publicly available software packages and web services. During this period, we have greatly expanded Primer3’s functionality. In this article, we describe Primer3’s current capabilities, emphasizing recent improvements. The most notable enhancements incorporate more accurate thermodynamic models in the primer design process, both to improve melting temperature prediction and to reduce the likelihood that primers will form hairpins or dimers. Additional enhancements include more precise control of primer placement—a change motivated partly by opportunities to use whole-genome sequences to improve primer specificity. We also added features to increase ease of use, including the ability to save and re-use parameter settings and the ability to require that individual primers not be used in more than one primer pair. We have made the core code more modular and provided cleaner programming interfaces to further ease integration with other software. These improvements position Primer3 for continued use with genome-scale data in the decade ahead.

7,286 citations

Journal ArticleDOI
TL;DR: It is concluded that cox1 sequencing, or ‘barcoding’, can be used to identify fish species.
Abstract: GC than sharks (44.7% versus 41.0%), again largely due to higher GC in the 3rd codon position in the former (36.3% versus 26.8%). Average within-species, genus, family, order and class Kimura two parameter (K2P) distances were 0.39%, 9.93%, 15.46%, 22.18% and 23.27%, respectively. All species could be differentiated by their cox1 sequence, although single individuals of each of two species had haplotypes characteristic of a congener. Although DNA barcoding aims to develop species identification systems, some phylogenetic signal was apparent in the data. In the neighbourjoining tree for all 754 sequences, four major clusters were apparent: chimaerids, rays, sharks and teleosts. Species within genera invariably clustered, and generally so did genera within families. Three taxonomic groups—dogfishes of the genus Squalus, flatheads of the family Platycephalidae, and tunas of the genus Thunnus—were examined more closely. The clades revealed after bootstrapping generally corresponded well with expectations. Individuals from operational taxonomic units designated as Squalus species B through F formed individual clades, supporting morphological evidence for each of these being separate species. We conclude that cox1 sequencing, or ‘barcoding’, can be used to identify fish species.

3,212 citations

Journal ArticleDOI
TL;DR: The evidence that the evolution of breeding systems of animals and plants has been significantly influenced by the occurrence of inbreeding depression is reviewed, and the contemporary genetic theory of inmarriage depression and heterosis and the experimental data concerning the strength of in breeding depression are considered.
Abstract: The harmful effects of close inbreeding have been noticed for many centuries (34, 35, 165). With the rise of Mendelian genetics, it was realized that the main genetic consequence of inbreeding is homozygosis (165, Ch. 2). Two main theories were early proposed to account for inbreeding depression and its converse, heterosis (the increase in vigor observed in an F1 between two inbred lines). These are the overdominance and partial dominance hypotheses, discussed in more detail below. Research into this question has continued up to the present, and this is one of the topics that we discuss. Darwin (35, 36) was the first to point out that the evident adaptations of many plants for ensuring outcrossing could be understood in terms of the selective advantage of avoiding inbreeding depression. We review the evidence that the evolution of breeding systems of animals and plants has been significantly influenced by the occurrence of inbreeding depression. In order to do this, we consider the contemporary genetic theory of inbreeding depression and heterosis, and the experimental data concerning the strength of inbreeding depression. We emphasize data and theory relevant to natural, rather than domesticated, populations as we are chiefly concerned to evaluate the evolutionary significance of inbreeding depression. We do not attempt to give a complete bibliography of this very extensive field but try to concentrate on what seem to be the most significant findings in relation to this aim.

3,135 citations

Book ChapterDOI
29 Aug 2012
TL;DR: It was established previously that the mitochondrial gene cytochrome c oxidase I can serve as the core of a global bioidentification system for animals and a new tools were developed recently to be complementary markers for (COI) DNA barcoding.
Abstract: Although much biological research depends upon species diagnoses, taxonomic expertise is collapsing. We are convinced that the sole prospect for a sustainable identification capability lies in the construction of systems that employ DNA sequences as taxon ‘barcodes’. It was established previously that the mitochondrial gene cytochrome c oxidase I (COI) can serve as the core of a global bioidentification system for animals. A new tools were developed recently to be complementary markers for (COI) DNA barcoding.

2,945 citations