Samuel Brown

Dr. Samuel Brown

orcid

Research Focus & Metrics

Academic Career Length

21Years (2006-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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16 January 2012 in Molecular Ecology Resources
Verified
Journal Article
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SBSamuel Brown
Samuel Brown
RCRupert A. Collins
Rupert A. Collins
SBStephane Boyer
Stephane Boyer
MLMarie‐Caroline Lefort
Marie‐Caroline Lefort
JMJagoba Malumbres-Olarte
Jagoba Malumbres-Olarte
RCRobert H. Cruickshank
Robert H. Cruickshank

20 January 2012 in PLOS ONE
Verified
Journal Article
Open access
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RCRupert A. Collins
Rupert A. Collins
KAKaren Armstrong
Karen Armstrong
RMRudolf Meier
Rudolf Meier
YYYouguang Yi
Youguang Yi
SBSamuel Brown
Samuel Brown
CJColin Johnston
Colin Johnston
Poorly regulated international trade in ornamental fishes poses risks to both biodiversity and economic activity via invasive alien species and exotic pathogens. Border security officials need robust tools to confirm identifications, often requiring hard-to-obtain taxonomic literature and expertise. DNA barcoding offers a potentially attractive tool for quarantine inspection, but has yet to be scrutinised for aquarium fishes. Here, we present a barcoding approach for ornamental cyprinid fishes by: (1) expanding current barcode reference libraries; (2) assessing barcode congruence with morphological identifications under numerous scenarios (e.g. inclusion of GenBank data, presence of singleton species, choice of analytical method); and (3) providing supplementary information to identify difficult species. We sampled 172 ornamental cyprinid fish species from the international trade, and provide data for 91 species currently unrepresented in reference libraries (GenBank/Bold). DNA barcodes were found to be highly congruent with our morphological assignments, achieving success rates of 90–99%, depending on the method used (neighbour-joining monophyly, bootstrap, nearest neighbour, GMYC, percent threshold). Inclusion of data from GenBank (additional 157 spp.) resulted in a more comprehensive library, but at a cost to success rate due to the increased number of singleton species. In addition to DNA barcodes, our study also provides supporting data in the form of specimen images, morphological characters, taxonomic bibliography, preserved vouchers, and nuclear rhodopsin sequences. Using this nuclear rhodopsin data we also uncovered evidence of interspecific hybridisation, and highlighted unrecognised diversity within popular aquarium species, including the endangered Indian barb Puntius denisonii. We demonstrate that DNA barcoding provides a highly effective biosecurity tool for rapidly identifying ornamental fishes. In cases where DNA barcodes are unable to offer an identification, we improve on previous studies by consolidating supplementary information from multiple data sources, and empower biosecurity agencies to confidently identify high-risk fishes in the aquarium trade.

29 May 2012 in PLOS ONE
Verified
Journal Article
Open access
PDF file
SBStephane Boyer
Stephane Boyer
SBSamuel Brown
Samuel Brown
RCRupert A. Collins
Rupert A. Collins
RCRobert H. Cruickshank
Robert H. Cruickshank
MLMarie-Caroline Lefort
Marie-Caroline Lefort
SWStephen D. Wratten
Stephen D. Wratten
DNA barcoding remains a challenge when applied to diet analyses, ancient DNA studies, environmental DNA samples and, more generally, in any cases where DNA samples have not been adequately preserved. Because the size of the commonly used barcoding marker (COI) is over 600 base pairs (bp), amplification fails when the DNA molecule is degraded into smaller fragments. However, relevant information for specimen identification may not be evenly distributed along the barcoding region, and a shorter target can be sufficient for identification purposes. This study proposes a new, widely applicable, method to compare the performance of all potential ‘mini-barcodes’ for a given molecular marker and to objectively select the shortest and most informative one. Our method is based on a sliding window analysis implemented in the new R package SPIDER (Species IDentity and Evolution in R). This method is applicable to any taxon and any molecular marker. Here, it was tested on earthworm DNA that had been degraded through digestion by carnivorous landsnails. A 100 bp region of 16 S rDNA was selected as the shortest informative fragment (mini-barcode) required for accurate specimen identification. Corresponding primers were designed and used to amplify degraded earthworm (prey) DNA from 46 landsnail (predator) faeces using 454-pyrosequencing. This led to the detection of 18 earthworm species in the diet of the snail. We encourage molecular ecologists to use this method to objectively select the most informative region of the gene they aim to amplify from degraded DNA. The method and tools provided here, can be particularly useful (1) when dealing with degraded DNA for which only small fragments can be amplified, (2) for cases where no consensus has yet been reached on the appropriate barcode gene, or (3) to allow direct analysis of short reads derived from massively parallel sequencing without the need for bioinformatic consolidation.

1 September 2012 in Molecular Phylogenetics and Evolution
Verified
Journal Article
Closed access
SBSamuel Brown
Samuel Brown
KAKaren Armstrong
Karen Armstrong
RCRobert H. Cruickshank
Robert H. Cruickshank

2 January 2014 in New Zealand Entomologist
Verified
Journal Article
Closed access
PLPhil Lester
Phil Lester
SBSamuel Brown
Samuel Brown
EEE. D. Edwards
E. D. Edwards
GHG. I. Holwell
G. I. Holwell
SPS. M. Pawson
S. M. Pawson
CWC. H. Watts
C. H. Watts
Here, we identify current high-priority issues in New Zealand entomology. These ‘critical issues’ were defined by being of national entomological interest, and in urgent need of research or attention. The issues were derived in consultation with the Entomological Society of New Zealand members and as part of a workshop at the 62nd New Zealand Entomological Society Conference. We present a list of nine priority areas (presented here without any ranking priority). These areas are: 1. conserving indigenous invertebrate diversity; 2. limiting predator pressure exerted by exotic vertebrate predators; 3. limiting the effects of invasive invertebrates, especially Vespula wasps in honeydew beech forests; understanding the influence of pesticides and pathogens on honey bees; 4. maintaining and enhancing efficient biosecurity systems to keep out invasive pests and diseases; 5. enhancing support for taxonomy; 6. enhancing entomological teaching, training and support for entomology graduates; 7. utilising the hidden knowledge of retired entomologists; and 8. supporting amateurs in entomology. For each of these topics we briefly discuss the state of the current situation or knowledge gaps. We consider this a road map to enhance entomology in New Zealand.

8 December 2021 in Risk Analysis
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Journal Article
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LJLisa E. Jamieson
Lisa E. Jamieson
OWOwen Woodberry
Owen Woodberry
SMSteven Mascaro
Steven Mascaro
NMNicolas Meurisse
Nicolas Meurisse
RJRodelyn Jaksons
Rodelyn Jaksons
MOMichael Ormsby
Michael Ormsby