• Extended Pelagic Life in a Bathybenthic Octopus

      Villanueva, Roger; Laptikhovsky, Vladimir V; Piertney, Stuart B; Fernández-Álvarez, Fernando Ángel; Collins, Martin A; Ablett, J; Escánez, Alejandro (Frontiers Media SA, 2020-11-20)
      Planktonic stages of benthic octopuses can reach relatively large sizes in some species, usually in oceanic, epipelagic waters while living as part of the macroplankton. These young octopuses appear to delay settlement on the seabed for an undetermined period of time that is probably longer than for those octopus paralarvae living in coastal, neritic waters. The reason for this delay is unknown and existing information about their biology is very scarce. Here we report on the presence of juvenile and subadult forms of the bathybenthic octopus Pteroctopus tetracirrhus in oceanic waters of the South and North Atlantic and its association with the pyrosomid species Pyrosoma atlanticum, apparently used by the octopus as a refuge or shelter. The relatively large size of the P. tetracirrhus living in oceanic waters as the individuals reported here, together with the morphological characteristics of this bathybenthic species including its gelatinous body, minute suckers embedded in swollen skin and the deep interbrachial web, indicates that P. tetracirrhus may be considered a model of a transitional octopus species that is colonizing the pelagic environment by avoiding descending to the bathyal benthos. This process seems to occur in the same way as in the supposed origin of the ctenoglossan holopelagic octopods of the families Amphitretidae, Bolitaenidae, and Vitreledonellidae, which have arisen via neoteny from the planktonic paralarval stages of benthic octopuses.
    • Evolutionary history of the Galápagos Rail revealed by ancient mitogenomes and modern samples

      Chaves, Jaime A; Martinez-Torres, Pedro J; Depino, Emiliano A; Espinoza-Ulloa, Sebastian; García-Loor, Jefferson; Beichman, Annabel; Stervander, Martin (MDPI, 2020-11-12)
      The biotas of the Galápagos Islands are one of the best studied island systems and have provided a broad model for insular species’ origins and evolution. Nevertheless, some locally endemic taxa, such as the Galápagos Rail Laterallus spilonota, remain poorly characterized. Owing to its elusive behavior, cryptic plumage, and restricted distribution, the Galápagos Rail is one of the least studied endemic vertebrates of the Galapagos Islands. To date, there is no genetic data for this species, leaving its origins, relationships to other taxa, and levels of genetic diversity uncharacterized. This lack of information is critical given the adverse fate of island rail species around the world in the recent past. Here, we examine the genetics of Galápagos Rails using a combination of mitogenome de novo assembly with multilocus nuclear and mitochondrial sequencing from both modern and historical samples. We show that the Galápagos Rail is part of the “American black rail clade”, sister to the Black Rail L. jamaicensis, with a colonization of Galápagos dated to 1.2 million years ago. A separate analysis of one nuclear and two mitochondrial markers in the larger population samples demonstrates a shallow population structure across the islands, possibly due to elevated island connectivity. Additionally, birds from the island Pinta possessed the lowest levels of genetic diversity, possibly reflecting past population bottlenecks associated with overgrazing of their habitat by invasive goats. The modern and historical data presented here highlight the low genetic diversity in this endemic rail species and provide useful information to guide conservation efforts.
    • A proposed solution to a lengthy dispute: what is Leptinaria (uni)lamellata (Mollusca, Gastropoda, Achatinidae)?

      Breure, ASH; Ablett, J; Audibert, C (Cernuelle, 2020-11-01)
      The taxonomic position and the publication dates of both Achatina lamellata Potiez & Michaud, 1835 and Helix unilamellata d’Orbigny, 1835 are discussed. The dispute concerning the correct publication date of Potiez & Michaud is analysed and a collation of their Atlas is compared to the sheets of their main text, leading to the most likely scenario that the name Achatina lamellata became available in October 1838. The discovery of material ex auctore of this taxon enables us to establish it as a junior synonym of d’Orbigny’s taxon, which was published in March 1838. The correct name is thus Leptinaria unilamellata (d’Orbigny, 1838).
    • Synthetic and semi-synthetic fibre ingestion by mesopelagic fishes from Tristan da Cuhna and St Helena, South Atlantic

      McGoran, Alexandra; Maclaine, James; Clark, Paul; Morritt, David (2020-11)
      As part of the Blue Belt Programme, a marine survey of British Overseas Territories funded by the UK Government, RRS Discovery trawled at depths of between the surface and 1000m around Tristan da Cuhna and St Helena. Fishes were examined for microplastic ingestion. This work was supported by the National Environmental Research Council [grant number NE/L002485/1] with co-sponsorship from a Fishmongers' Company Fisheries Charity Trust CASE Partnership. Specimens were collected onboard RRS Discover as part of the Blue Belt Programme, which is funded by the UK Government in collaboration with CEFAS and BAS.
    • An urban Blitz with a twist: rapid biodiversity assessment using aquatic environmental DNA

      Hupało, K; Majaneva, M; Czachur, MV; Sire, L; Marquina, D; Lijtmaer, DA; Ivanov, V; Leidenberger, S; Čiampor, F; Čiamporová‐Zaťovičová, Z; et al. (Wiley, 2020-10-24)
      As global biodiversity declines, there is an increasing need to create an educated and engaged society. Having people of all ages participate in measuring biodiversity where they live helps to create awareness. Recently, the use of environmental DNA (eDNA) for biodiversity surveys has gained momentum. Here, we explore whether sampling eDNA and sequencing it can be used as a means of rapidly surveying urban biodiversity for educational purposes. We sampled 2 × 1 L of water from each of 15 locations in the city of Trondheim, Norway, including a variety of freshwater, marine, and brackish habitats. DNA was extracted, amplified in triplicate targeting the barcoding fragment of COI gene, and sequenced. The obtained data were analyzed on the novel mBRAVE platform, an online open‐access software and computing resource. The water samples were collected in 2 days by two people, and the laboratory analysis was completed in 5 days by one person. Overall, we detected the presence of 506 BINs identified as belonging to 435 taxa, representing at least 265 putative species. On average, only 5.4% of the taxa were shared among six replicates per site. Based on the observed diversity, three distinct clusters were detected and related to the geographic distribution of sites. There were some taxa shared between the habitats, with a substantial presence of terrestrial biota. Here we propose a new form of BioBlitz, where with noninvasive sampling effort combined with swift processing and straightforward online analyses, hundreds of species can be detected. Thus, using eDNA analysis of water is useful for rapid biodiversity surveys and valuable for educational purposes. We show that rapid eDNA surveys, combined with openly available services and software, can be used as an educational tool to raise awareness about the importance of biodiversity.
    • A revision of the Maechidiini Burmeister, 1855 (Coleoptera: Scarabaeidae: Melolonthinae) from the Indo-Australian transition zone, and the first record of the tribe west of Wallace’s Line

      Telnov, Dmitry (2020-10-19)
      Features of the Maechidiini (Scarabaeidae: Melolonthinae) genera Maechidius Macleay, 1819, Epholcis Waterhouse, 1875 and Paramaechidius Frey, 1969 are critically revised and a new synonymy is proposed: Maechidius = Epholcis syn. nov. = Paramaechidius syn. nov. A key to and an annotated checklist of Maechidiini from the Indo-Australian transition zone are presented for the first time. Thirty-five new species are described, namely Maechidius aiyura sp. nov., M. alesbezdeki sp. nov., M. awu sp. nov., M. babyrousa sp. nov., M. bintang sp. nov., M. boessnecki sp. nov., M. brocki sp. nov., M. caperatus sp. nov., M. ciliatus sp. nov., M. crypticus sp. nov., M. dani sp. nov., M. deltouri sp. nov., M. dendrolagus sp. nov., M. hamatus sp. nov., M. kazantsevi sp. nov., M. konjo sp. nov., M. lapsus sp. nov., M. legalovi sp. nov., M. leucopsar sp. nov., M. longipes sp. nov., M. mailu sp. nov., M. maleo sp. nov., M. merdeka sp. nov., M. miklouhomaclayi sp. nov., M. nepenthephilus sp. nov., M. owenstanleyi sp. nov., M. riedeli sp. nov., M. similis sp. nov., M. skalei sp. nov., M. sougb sp. nov., M. suwawa sp. nov., M. trivialis sp. nov., M. ursus sp. nov., M. weigeli sp. nov. and M. yamdena sp. nov. Six new synonyms are proposed: Maechidius Macleay, 1819 = Epholcis Waterhouse, 1875 syn. nov. = Paramaechidius Frey, 1969 syn. nov., Maechidius esau Heller, 1914 = M. setosus Moser, 1920 syn. nov. = M. setosellus Frey, 1969 syn. nov., Maechidius heterosquamosus Heller, 1910 comb. rest. = Paramaechidius clypeatus Frey, 1969 syn. nov. and Maechidius paupianus Heller, 1910 = M. arrowi Frey, 1969 syn. nov. The first records of Maechidiini from the Tanimbar Islands (Yamdena), Sangihe Islands (Sangir) and Lesser Sunda Islands (Bali) are documented, of which the latter two are the northern- and westernmost known records of Maechidius and of the tribe Maechidiini. Lectotypes are designated for 23 species. Fifteen new combinations are proposed and the original combination to Maechidius is restored for four species. Ecological data are presented for the first time for selected Papuan and Wallacean species. Type material of Wallacean and Papuan Maechidiini is depicted for the first time. A key to species is given. In total, 78 species of Maechidiini are confirmed for the Indo-Australian transition zone.
    • Climatic oscillations in Quaternary have shaped the co‑evolutionary patterns between the Norway spruce and its host‑associated herbivore

      Jakub, G; Andrzej, O; Robert, R; Igor, C; Katarzyna, M; Radosław, P; Matti, L; Mauro, G; Gernot, H; Vytautas, T; et al. (Springer Nature, 2020-10-05)
      During the Last Glacial Maximum in the Northern Hemisphere, expanding ice sheets forced a large number of plants, including trees, to retreat from their primary distribution areas. Many host-associated herbivores migrated along with their host plants. Long-lasting geographic isolation between glacial refugia could have been led to the allopatric speciation in separated populations. Here, we have studied whether the migration history of the Norway spruce Picea abies in Quaternary has affected its host-associated herbivorous beetle—Monochamus sartor. By using microsatellite markers accompanied by the geometric morphometrics analysis of wing venation, we have revealed the clear geographic structure of M. sartor in Eurasia, encompassing two main clusters: southern (Alpine–Carpathian) and eastern (including northeastern Europe and Asia), which reflects the northern and southern ecotypes of its host. The two beetles’ lineages probably diverged during the Pleniglacial (57,000—15,000 BC) when their host tree species was undergoing significant range fragmentation and experienced secondary contact during post-glacial recolonization of spruce in the Holocene. A secondary contact of divergent lineages of M. sartor has resulted in the formation of the hybrid zone in northeastern Europe. Our findings suggest that the climatic oscillations during the Pleistocene have driven an insect-plant co-evolutionary process, and have contributed to the formation of the unique biodiversity of Europe.
    • Evaluation of DNA barcode libraries used in the UK and developing an action plan to fill priority gaps

      Price, BW; Briscoe, AG; Misra, Raju; Broad, G (Natural England, 2020-10)
      There are approximately 76,000 eukaryote species recognised in the UK, and while we know some of them in great detail, the majority of these species are poorly known, and hundreds of new species are discovered each year. DNA barcoding uses a short, standardised segment of an organism’s genome for identification by comparison to a reference library; however, the UK lags behind several countries in Europe and North America in that we lack trusted, reliable and openly accessible reference sequences for key UK taxa. This report is the first step in rectifying this by engaging diverse stakeholders to facilitate collaboration and coordination; providing robust stakeholder-based and independent assessment of the current state of reference libraries available for all known UK taxa; and prioritising key taxa. A survey was developed and shared with the UK research and end user community, receiving 80 responses from a wide range of stakeholders and covering the focal taxa / assemblages and habitats; the DNA reference libraries in use, their quality assurance and perceived coverage. A formal gap analysis of the public DNA data in major DNA reference libraries highlighted that an estimated 52% of UK species have publicly available DNA data of some sort; however, coverage in gene specific reference libraries varies greatly (eg 2 – 52%), as does the associated quality assurance. Priority taxa highlighted by end users had coverage in reference libraries ranging from almost complete, in the case of known invasive non-native species, to significant coverage (71%) for taxa with conservation designations. However, these data also vary by kingdom and reference library, as does the associated quality assurance. If taking a strict requirement of DNA data provided by UK specimens and held in UK repositories, for robust QC and QA, then the proportion of UK species with public DNA data in reference libraries falls to less than 4% in the largest reference library assessed (BOLD). While standard genes for DNA-based identification have essentially been established, more work is required to establish the priority taxa required for regulatory delivery in contrast to taxa that are surveyed in a non-regulatory framework. Several barriers to the development of barcode libraries were highlighted, the most relevant being sustained large scale funding, expertise, capacity, laboratory skills and equipment, quality control and assurance, collecting logistics (eg permits and access) and communication. Significant opportunities identified include a large network of interested experts, several organisations with significant delivery capabilities, current large-scale projects and funding opportunities, emerging technologies and the economy of scale for DNA sequencing. Following a stakeholder workshop, we have outlined a concise action plan to provide reliable, open access reference sequences, linked to open access vouchers, identified by known experts, to facilitate UK academic and regulatory aims.
    • A Horizon Scan of research priorities to inform policies aimed at reducing the harm of plastic pollution to biota

      Provencher, JF; Liboiron, M; Borrelle, SB; Bond, AL; Rochman, C; Lavers, JL; Avery-Gomm, S; Yamashita, R; Ryan, PG; Lusher, AL; et al. (Elsevier, 2020-09-01)
      Plastic pollution in the oceans is a priority environmental issue. The recent increase in research on the topic, coupled with growing public awareness, has catalyzed policymakers around the world to identify and implement solutions that minimize the harm caused by plastic pollution. To aid and coordinate these efforts, we surveyed experts with scientific experience identified through their peer-reviewed publications. We asked experts about the most pressing research questions relating to how biota interact with plastic pollution that in turn can inform policy decisions and research agendas to best contribute to understanding and reducing the harm of plastic pollution to biota. We used a modified Horizon Scan method that first used a subgroup of experts to generate 46 research questions on aquatic biota and plastics, and then conducted an online survey of researchers globally to prioritize questions in terms of their importance to inform policy development. One hundred and fifteen experts from 29 countries ranked research questions in six themes. The questions were ranked by urgency, indicating which research should be addressed immediately, which can be addressed later, and which are of limited relevance to inform action on plastics as an environmental pollutant. We found that questions relating to the following four themes were the most commonly top-ranked research priorities: (i) sources, circulation and distribution of plastics, (ii) type of harm from plastics, (iii) detection of ingested plastics and the associated problems, and (iv) related economies and policy to ingested plastics. While there are many research questions on the topic of impacts of plastic pollution on biota that could be funded and investigated, our results focus collective priorities in terms of research that experts believe will inform effective policy and on-the-ground conservation.
    • Ineffectiveness of light emitting diodes as underwater deterrents for Long-tailed Ducks Clangula hyemalis

      Cantlay, JC; Bond, AL; Wells-Berlin, AM; Crawford, R; Martin, GR; Rouxel, Y; Peregoy, S; McGrew, KA; Portugal, SJ (Elsevier BV, 2020-09-01)
      Gillnet bycatch accounts for over 400,000 bird mortalities worldwide every year, affectinga wide variety of species, especially those birds that dive when foraging. Technologicalsolutions to improve gillnet visibility or deter birds from approaching nets, such as LEDlights, are essential for aiding diving birds to perceive nets as a hazard. Designing suchsolutions requires obtaining visual and behavioural ecology information from species toassess their ability to see the warning devices, and to examine their behavioural responsesto them. Seaducks, particularly Long-tailed DucksClangula hyemalis,have high bycatchmortality rates. We examined the visualfields of four Long-tailed Ducks to understandtheir three-dimensional view around the head. The visualfield characteristics of thisspecies indicate a reliance on visual guidance for foraging associated with their capture ofvaried, mobile prey in their generalist diet. We subsequently conducted dive tank trials totest the effectiveness of 12 different LED treatments as visual deterrents to the underwaterforaging behaviour of 8 Long-tailed Ducks. During each trial, ducks were offered foodrewards from a specific underwater location in a dive tank, having the choice of whether totake the food or not. At the same time, they were exposed to either one LED light or thecontrol (no light) to determine whether the presence of each light affected the foragingsuccess rate of dives compared to the control. Exposure of ducks to all 13 treatmentcombinations was randomised over the trial period. White lights with an increasingflashrate were shown to have a significant positive effect on foraging success, and likely acted asa visual attractant, rather than as a deterrent. No light treatment significantly reduced theforaging success of ducks. LED lights did not inhibit the feeding of Long-tailed Ducks. Suchlights may be ineffective as underwater visual deterrents when deployed on gillnets, whilewhiteflashing lights may make foraging sites more attractive to Long-tailed Ducks.
    • Deep-Sea Mining: Processes and Impacts

      Jones, Daniel; Amon, Diva; Chapman, Abbie (Oxford University Press, 2020-08-27)
      Mining the extensive accumulations of minerals on the seafloor of the deep ocean can provide important resources but also has the potential to lead to widespread environmental impacts. Some of these impacts are unknown but there are expected to be differences between the mining of the three main resource types: polymetallic nodules, seafloor massive sulphides and cobalt-rich crusts. Here we detail the mining processes as well as the expected impacts of mining and discuss their potential effects to deep-ocean ecosystems. We also highlight the missing evidence needed to underpin effective environmental management and regulation of the nascent deep-sea mining industry.
    • Seasonal ingestion of anthropogenic debris in an urban population of gulls

      Stewart, LG; Lavers, JL; Grant, ML; Puskic, PS; Bond, AL (Elsevier BV, 2020-08-15)
      Gulls are generalist seabirds, increasingly drawn to urban environments where many species take advantage of abundant food sources, such as landfill sites. Despite this, data on items ingested at these locations, including human refuse, is limited. Here we investigate ingestion of prey and anthropogenic debris items in boluses (regurgitated pellets) from Pacific Gulls (Larus pacificus). A total of 374 boluses were collected between 2018 and 2020 in Tasmania. Debris was present in 92.51% of boluses (n = 346), with plastic (86.63%, n = 324) and glass (64.71%, n = 242) being the most prominent types. An abundance of intact, household items (e.g., dental floss, food wrappers) suggest the gulls regularly feed at landfill sites. In addition, the boluses are deposited at a roosting site located within an important wetland, thus we propose that the gulls may be functioning as a previously unrecognised vector of anthropogenic debris from urban centres to aquatic environments.
    • Ensuring tests of conservation interventions build on existing literature

      Sutherland, WJ; Alvarez‐Castañeda, ST; Amano, T; Ambrosini, R; Atkinson, P; Baxter, JM; Bond, AL; Boon, PJ; Buchanan, KL; Barlow, J; et al. (Wiley, 2020-08-11)
    • Biological archives reveal contrasting patterns in trace element concentrations in pelagic seabird feathers over more than a century

      Bond, AL; Lavers, JL (Elsevier, 2020-08-01)
      Contamination of diverse environments and wild species by some contaminants is projected to continue and increase in coming decades. In the marine environment, large volumes of data to assess how concentrations have changed over time can be gathered from indicator species such as seabirds, including through sampling feathers from archival collections and museums. As apex predators, Flesh-footed Shearwaters (Ardenna carneipes) are subject to high concentrations of bioaccumulative and biomagnifying contaminants, and reflect the health of their local marine environment. We analysed Flesh-footed Shearwater feathers from Australia from museum specimens and live birds collected between 1900 and 2011 and assessed temporal trends in three trace elements of toxicological concern: cadmium, mercury, and lead. Concentrations of cadmium increased by 1.5% per year (95% CI: +0.6, +3.0), while mercury was unchanged through the time series (−0.3% per year; 05% CI: -2.1, +1.5), and lead decreased markedly (−2.1% per year, 95% CI: -3.2, −1.0). A reduction in birds’ trophic position through the 20th century, and decreased atmospheric emissions were the likely driving factors for mercury and lead, respectively. By combining archival material from museum specimens with contemporary samples, we have been able to further elucidate the potential threats posed to these apex predators by metal contamination.
    • Deep-Sea Misconceptions Cause Underestimation of Seabed-Mining Impacts

      Smith, CR; Tunnicliffe, V; Colaço, A; Drazen, JC; Gollner, S; Levin, LA; Mestre, NC; Metaxas, A; Molodtsova, TN; Morato, T; et al. (Elsevier, 2020-07-31)
      Scientific misconceptions are likely leading to miscalculations of the environmental impacts of deepseabed mining. These result from underestimating mining footprints relative to habitats targeted and poor understanding of the sensitivity, biodiversity, and dynamics of deep-sea ecosystems. Addressing these misconceptions and knowledge gaps is needed for effective management of deep-seabed mining.
    • Evidence of Vent-Adaptation in Sponges Living at the Periphery of Hydrothermal Vent Environments: Ecological and Evolutionary Implications

      Georgieva, MN; Taboada, Sergio; Riesgo, A; Díez-Vives, C; De Leo, FC; Jeffreys, RM; Copley, JT; Little, Crispin; Ríos, P; Cristobo, J; et al. (Frontiers Media SA, 2020-07-24)
      The peripheral areas of deep-sea hydrothermal vents are often inhabited by an assemblage of animals distinct to those living close to vent chimneys. For many such taxa, it is considered that peak abundances in the vent periphery relate to the availability of hard substrate as well as the increased concentrations of organic matter generated at vents, compared to background areas. However, the peripheries of vents are less well-studied than the assemblages of vent-endemic taxa, and the mechanisms through which peripheral fauna may benefit from vent environments are generally unknown. Understanding this is crucial for evaluating the sphere of influence of hydrothermal vents and managing the impacts of future human activity within these environments, as well as offering insights into the processes of metazoan adaptation to vents. In this study, we explored the evolutionary histories, microbiomes and nutritional sources of two distantly-related sponge types living at the periphery of active hydrothermal vents in two different geological settings (Cladorhiza from the E2 vent site on the East Scotia Ridge, Southern Ocean, and Spinularia from the Endeavour vent site on the Juan de Fuca Ridge, North-East Pacific) to examine their relationship to nearby venting. Our results uncovered a close sister relationship between the majority of our E2 Cladorhiza specimens and the species Cladorhiza methanophila, known to harbor and obtain nutrition from methanotrophic symbionts at cold seeps. Our microbiome analyses demonstrated that both E2 Cladorhiza and Endeavour Spinularia sp. are associated with putative chemosynthetic Gammaproteobacteria, including Thioglobaceae (present in both sponge types) and Methylomonaceae (present in Spinularia sp.). These bacteria are closely related to chemoautotrophic symbionts of bathymodiolin mussels. Both vent-peripheral sponges demonstrate carbon and nitrogen isotopic signatures consistent with contributions to nutrition from chemosynthesis. This study expands the number of known associations between metazoans and potentially chemosynthetic Gammaproteobacteria, indicating that they can be incredibly widespread and also occur away from the immediate vicinity of chemosynthetic environments in the vent-periphery, where these sponges may be adapted to benefit from dispersed vent fluids.
    • Metabarcoding unsorted kick‐samples facilitates macroinvertebrate‐based biomonitoring with increased taxonomic resolution, while outperforming environmental DNA

      Pereira-da-Conceicoa, Lyndall; Elbrecht, V; Hall, Andie; Briscoe, AG; Barber‐James, H; Price, BW (Wiley, 2020-07-21)
      Pereira‐da‐Conceicoa, L, Elbrecht, V, Hall, A, Briscoe, A, Barber‐James, H, Price, B. Metabarcoding unsorted kick‐samples facilitates macroinvertebrate‐based biomonitoring with increased taxonomic resolution, while outperforming environmental DNA. Environmental DNA. 2020; 00: 1– 19. https://doi.org/10.1002/edn3.116
    • A critical review of harm associated with plastic ingestion on vertebrates

      Puskic, PS; Lavers, JL; Bond, AL (Elsevier BV, 2020-07-07)
      Studies documenting plastic ingestion in animals have increased in recent years. Many do not describe the less conspicuous, sub-lethal impacts of plastic ingestion, such as reduced body condition or physiological changes. This means the severity of this global problem may have been underestimated. We conducted a critical review on the sub-lethal impacts of plastic ingestion on marine vertebrates (excluding fish). We found 34 papers which tried to measure plastics' impact using a variety of tools, and less than half of these detected any impact. The most common tools used were visual observations and body condition indices. Tools that explore animal physiology, such as histopathology, are a promising future approach to uncover the sub-lethal impacts of plastic ingestion in vertebrates. We encourage exploring impacts on species beyond the marine environment, using multiple tools or approaches, and continued research to discern the hidden impacts of plastic on global wildlife.
    • Disparities in the analysis of morphological disparity

      Guillerme, T; Cooper, N; Brusatte, SL; Davis, KE; Jackson, AL; Gerber, S; Goswami, A; Healy, K; Hopkins, MJ; Jones, MEH; et al. (The Royal Society, 2020-07-01)
      Analyses of morphological disparity have been used to characterize and investigate the evolution of variation in the anatomy, function and ecology of organisms since the 1980s. While a diversity of methods have been employed, it is unclear whether they provide equivalent insights. Here, we review the most commonly used approaches for characterizing and analysing morphological disparity, all of which have associated limitations that, if ignored, can lead to misinterpretation. We propose best practice guidelines for disparity analyses, while noting that there can be no ‘one-size-fits-all’ approach. The available tools should always be used in the context of a specific biological question that will determine data and method selection at every stage of the analysis.
    • The increased sensitivity of qPCR in comparison to Kato-Katz is required for the accurate assessment of the prevalence of soil-transmitted helminth infection in settings that have received multiple rounds of mass drug administration

      Dunn, JC; PAPAIAKOVOU, MARINA; Han, KT; Chooneea, D; Bettis, AA; Wyine, NY; Lwin, AMM; Maung, NS; Misra, Raju; Littlewood, T; et al. (Springer Science and Business Media LLC, 2020-06-24)
      Background The most commonly used diagnostic tool for soil-transmitted helminths (STH) is the Kato-Katz (KK) thick smear technique. However, numerous studies have suggested that the sensitivity of KK can be problematic, especially in low prevalence and low intensity settings. An emerging alternative is quantitative polymerase chain reaction (qPCR). Methods In this study, both KK and qPCR were conducted on stool samples from 648 participants in an STH epidemiology study conducted in the delta region of Myanmar in June 2016. Results Prevalence of any STH was 20.68% by KK and 45.06% by qPCR. Prevalence of each individual STH was also higher by qPCR than KK, the biggest difference was for hookworm with an approximately 4-fold increase between the two diagnostic techniques. Prevalence of Ancylostoma ceylanicum, a parasite predominately found in dogs, was 4.63%, indicating that there is the possibility of zoonotic transmission in the study setting. In individuals with moderate to high intensity infections there is evidence for a linear relationship between eggs per gram (EPG) of faeces, derived from KK, and DNA copy number, derived from qPCR which is particularly strong for Ascaris lumbricoides. Conclusions The use of qPCR in low prevalence settings is important to accurately assess the epidemiological situation and plan control strategies for the ‘end game’. However, more work is required to accurately assess STH intensity from qPCR results and to reduce the cost of qPCR so that is widely accessible in STH endemic countries.