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1.
Proc Natl Acad Sci U S A ; 119(33): e2120584119, 2022 08 16.
Artículo en Inglés | MEDLINE | ID: mdl-35939701

RESUMEN

Understanding and communicating the environmental impacts of food products is key to enabling transitions to environmentally sustainable food systems [El Bilali and Allahyari, Inf. Process. Agric. 5, 456-464 (2018)]. While previous analyses compared the impacts of food commodities such as fruits, wheat, and beef [Poore and Nemecek, Science 360, 987-992 (2018)], most food products contain numerous ingredients. However, because the amount of each ingredient in a product is often known only by the manufacturer, it has been difficult to assess their environmental impacts. Here, we develop an approach to overcome this limitation. It uses prior knowledge from ingredient lists to infer the composition of each ingredient, and then pairs this with environmental databases [Poore and Nemecek Science 360, 987-992 (2018); Gephart et al., Nature 597, 360-365 (2021)] to derive estimates of a food product's environmental impact across four indicators: greenhouse gas emissions, land use, water stress, and eutrophication potential. Using the approach on 57,000 products in the United Kingdom and Ireland shows food types have low (e.g., sugary beverages, fruits, breads), to intermediate (e.g., many desserts, pastries), to high environmental impacts (e.g., meat, fish, cheese). Incorporating NutriScore reveals more nutritious products are often more environmentally sustainable but there are exceptions to this trend, and foods consumers may view as substitutable can have markedly different impacts. Sensitivity analyses indicate the approach is robust to uncertainty in ingredient composition and in most cases sourcing. This approach provides a step toward enabling consumers, retailers, and policy makers to make informed decisions on the environmental impacts of food products.


Asunto(s)
Ambiente , Abastecimiento de Alimentos , Animales , Bovinos , Gases de Efecto Invernadero , Carne , Reino Unido
2.
Proc Biol Sci ; 290(2010): 20230657, 2023 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-37909084

RESUMEN

A universal paradigm describing patterns of speciation across the tree of life has been debated for decades. In marine organisms, inferring patterns of speciation using contemporary and historical patterns of biogeography is challenging due to the deficiency of species-level phylogenies and information on species' distributions, as well as conflicting relationships between species' dispersal, range size and co-occurrence. Most research on global patterns of marine fish speciation and biogeography has focused on coral reef or pelagic species. Carangoidei is an ecologically important clade of marine fishes that use coral reef and pelagic environments. We used sequence capture of 1314 ultraconserved elements (UCEs) from 154 taxa to generate a time-calibrated phylogeny of Carangoidei and its parent clade, Carangiformes. Age-range correlation analyses of the geographical distributions and divergence times of sister species pairs reveal widespread sympatry, with 73% of sister species pairs exhibiting sympatric geographical distributions, regardless of node age. Most species pairs coexist across large portions of their ranges. We also observe greater disparity in body length and maximum depth between sympatric relative to allopatric sister species. These and other ecological or behavioural attributes probably facilitate sympatry among the most closely related carangoids.


Asunto(s)
Peces , Simpatría , Animales , Filogenia , Arrecifes de Coral , Especiación Genética
3.
Mol Phylogenet Evol ; 186: 107841, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37327832

RESUMEN

Eleotridae (sleepers) and five smaller families are the earliest diverging lineages within Gobioidei. Most inhabit freshwaters in and around the Indo-Pacific, but Eleotridae also includes species that have invaded the Neotropics as well as several inland radiations in the freshwaters of Australia, New Zealand, and New Guinea. Previous efforts to infer phylogeny of these families have been based on sets of mitochondrial or nuclear loci and have yielded uncertain resolution of clades within Eleotridae. We expand the taxon sampling of previous studies and use genomic data from nuclear ultraconserved elements (UCEs) to infer phylogeny, then calibrate the hypothesis with recently discovered fossils. Our hypothesis clarifies ambiguously resolved relationships, provides a timescale for divergences, and indicates the core crown Eleotridae diverged over a short period 24.3-26.3 Ma in the late Oligocene. Within Eleotridae, we evaluate diversification dynamics with BAMM and find evidence for an overall slowdown in diversification over the past 35 Ma, but with a sharp increase 3.5 Ma in the genus Mogurnda, a clade of brightly colored species found in the freshwaters of Australia and New Guinea.


Asunto(s)
Peces , Perciformes , Humanos , Animales , Filogenia , Peces/genética , Perciformes/genética , Mitocondrias , Fósiles
4.
Syst Biol ; 71(1): 78-92, 2021 12 16.
Artículo en Inglés | MEDLINE | ID: mdl-34097063

RESUMEN

The Neotropics harbor the most species-rich freshwater fish fauna on the planet, but the timing of that exceptional diversification remains unclear. Did the Neotropics accumulate species steadily throughout their long history, or attain their remarkable diversity recently? Biologists have long debated the relative support for these museum and cradle hypotheses, but few phylogenies of megadiverse tropical clades have included sufficient taxa to distinguish between them. We used 1288 ultraconserved element loci spanning 293 species, 211 genera, and 21 families of characoid fishes to reconstruct a new, fossil-calibrated phylogeny and infer the most likely diversification scenario for a clade that includes a third of Neotropical fish diversity. This phylogeny implies paraphyly of the traditional delimitation of Characiformes because it resolves the largely Neotropical Characoidei as the sister lineage of Siluriformes (catfishes), rather than the African Citharinodei. Time-calibrated phylogenies indicate an ancient origin of major characoid lineages and reveal a much more recent emergence of most characoid species. Diversification rate analyses infer increased speciation and decreased extinction rates during the Oligocene at around 30 Ma during a period of mega-wetland formation in the proto-Orinoco-Amazonas. Three species-rich and ecomorphologically diverse lineages (Anostomidae, Serrasalmidae, and Characidae) that originated more than 60 Ma in the Paleocene experienced particularly notable bursts of Oligocene diversification and now account collectively for 68% of the approximately 2150 species of Characoidei. In addition to paleogeographic changes, we discuss potential accelerants of diversification in these three lineages. While the Neotropics accumulated a museum of ecomorphologically diverse characoid lineages long ago, this geologically dynamic region also cradled a much more recent birth of remarkable species-level diversity. [Biodiversity; Characiformes; macroevolution; Neotropics; phylogenomics; ultraconserved elements.].


Asunto(s)
Bagres , Characiformes , Animales , Biodiversidad , Fósiles , Filogenia
5.
Nature ; 535(7611): 241-5, 2016 07 14.
Artículo en Inglés | MEDLINE | ID: mdl-27362222

RESUMEN

Differences in phenological responses to climate change among species can desynchronise ecological interactions and thereby threaten ecosystem function. To assess these threats, we must quantify the relative impact of climate change on species at different trophic levels. Here, we apply a Climate Sensitivity Profile approach to 10,003 terrestrial and aquatic phenological data sets, spatially matched to temperature and precipitation data, to quantify variation in climate sensitivity. The direction, magnitude and timing of climate sensitivity varied markedly among organisms within taxonomic and trophic groups. Despite this variability, we detected systematic variation in the direction and magnitude of phenological climate sensitivity. Secondary consumers showed consistently lower climate sensitivity than other groups. We used mid-century climate change projections to estimate that the timing of phenological events could change more for primary consumers than for species in other trophic levels (6.2 versus 2.5-2.9 days earlier on average), with substantial taxonomic variation (1.1-14.8 days earlier on average).


Asunto(s)
Cambio Climático/estadística & datos numéricos , Ecosistema , Animales , Organismos Acuáticos , Clima , Conjuntos de Datos como Asunto , Predicción , Lluvia , Estaciones del Año , Especificidad de la Especie , Temperatura , Factores de Tiempo , Reino Unido
6.
PLoS Med ; 18(5): e1003647, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-34003863

RESUMEN

BACKGROUND: Consumption of free sugars in the UK greatly exceeds dietary recommendations. Public Health England (PHE) has set voluntary targets for industry to reduce the sales-weighted mean sugar content of key food categories contributing to sugar intake by 5% by 2018 and 20% by 2020. The aim of this study was to assess changes in the sales-weighted mean sugar content and total volume sales of sugar in selected food categories among UK companies between 2015 and 2018. METHODS AND FINDINGS: We used sales data from Euromonitor, which estimates total annual retail sales of packaged foods, for 5 categories-biscuits and cereal bars, breakfast cereals, chocolate confectionery, sugar confectionery, and yoghurts-for 4 consecutive years (2015-2018). This analysis includes 353 brands (groups of products with the same name) sold by 99 different companies. These data were linked with nutrient composition data collected online from supermarket websites over 2015-2018 by Edge by Ascential. The main outcome measures were sales volume, sales-weighted mean sugar content, and total volume of sugar sold by category and company. Our results show that between 2015 and 2018 the sales-weighted mean sugar content of all included foods fell by 5.2% (95% CI -9.4%, -1.4%), from 28.7 g/100 g (95% CI 27.2, 30.4) to 27.2 g/100 g (95% CI 25.8, 28.4). The greatest change seen was in yoghurts (-17.0% [95% CI -26.8%, -7.1%]) and breakfast cereals (-13.3% [95% CI -19.2%, -7.4%]), with only small reductions in sugar confectionery (-2.4% [95% CI -4.2%, -0.6%]) and chocolate confectionery (-1.0% [95% CI -3.1, 1.2]). Our results show that total volume of sugars sold per capita fell from 21.4 g/d (95% CI 20.3, 22.7) to 19.7 g/d (95% CI 18.8, 20.7), a reduction of 7.5% (95% CI -13.1%, -2.8%). Of the 50 companies representing the top 10 companies in each category, 24 met the 5% reduction target set by PHE for 2018. The key limitations of this study are that it does not encompass the whole food market and is limited by its use of brand-level sales data, rather than individual product sales data. CONCLUSIONS: Our findings show there has been a small reduction in total volume sales of sugar in the included categories, primarily due to reductions in the sugar content of yoghurts and breakfast cereals. Additional policy measures may be needed to accelerate progress in categories such as sugar confectionery and chocolate confectionery if the 2020 PHE voluntary sugar reduction targets are to be met.


Asunto(s)
Comercio/estadística & datos numéricos , Azúcares de la Dieta/análisis , Análisis de los Alimentos , Inglaterra , Alimentos
7.
Public Health Nutr ; 24(5): 819-825, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33109282

RESUMEN

OBJECTIVE: Online supermarkets are increasingly used both by consumers and as a source of data on the food environment. We compared product availability, nutritional information, front-of-pack (FOP) labelling, price and price promotions for food and drink products between physical and online supermarkets. DESIGN: For physical stores, we collected data on price, price promotions, FOP nutrition labels and nutrition information from a random sample of food and drinks from six UK supermarkets. For online stores, we used foodDB, a research-ready dataset of over 14 million observations of food and drink products available in online supermarkets. SETTING: Six large supermarket stores located near Oxford, UK. PARTICIPANTS: General sample with 295 food and drink products, plus boost samples for both fruit and vegetables, and alcohol. RESULTS: In the general sample, 85 % (95 % CI 80, 90 %) of products found in physical stores could be matched with an online product. Nutritional information found in the two settings was almost identical, for example, concordance correlation coefficient for energy = 0·995 (95 % CI 0·993, 0·996). The presence of FOP labelling and price promotions differed between the two settings (Cohen's kappa = 0·56 (95 % CI 0·45, 0·66) and 0·40 (95 % CI 0·26, 0·55), respectively). Prices were similar between online and physical supermarkets (concordance correlation coefficient > 0·9 for all samples). CONCLUSIONS: Product availability, nutritional information and prices sourced online for these six retailers are good proxies of those found in physical stores. Price promotions and FOP labelling vary between the two settings. Further research should investigate whether this could impact on health inequalities.


Asunto(s)
Comercio , Supermercados , Etiquetado de Alimentos , Abastecimiento de Alimentos , Humanos , Verduras
9.
PLoS Med ; 17(2): e1003025, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-32045418

RESUMEN

BACKGROUND: Dietary sugar, especially in liquid form, increases risk of dental caries, adiposity, and type 2 diabetes. The United Kingdom Soft Drinks Industry Levy (SDIL) was announced in March 2016 and implemented in April 2018 and charges manufacturers and importers at £0.24 per litre for drinks with over 8 g sugar per 100 mL (high levy category), £0.18 per litre for drinks with 5 to 8 g sugar per 100 mL (low levy category), and no charge for drinks with less than 5 g sugar per 100 mL (no levy category). Fruit juices and milk-based drinks are exempt. We measured the impact of the SDIL on price, product size, number of soft drinks on the marketplace, and the proportion of drinks over the lower levy threshold of 5 g sugar per 100 mL. METHODS AND FINDINGS: We analysed data on a total of 209,637 observations of soft drinks over 85 time points between September 2015 and February 2019, collected from the websites of the leading supermarkets in the UK. The data set was structured as a repeat cross-sectional study. We used controlled interrupted time series to assess the impact of the SDIL on changes in level and slope for the 4 outcome variables. Equivalent models were run for potentially levy-eligible drink categories ('intervention' drinks) and levy-exempt fruit juices and milk-based drinks ('control' drinks). Observed results were compared with counterfactual scenarios based on extrapolation of pre-SDIL trends. We found that in February 2019, the proportion of intervention drinks over the lower levy sugar threshold had fallen by 33.8 percentage points (95% CI: 33.3-34.4, p < 0.001). The price of intervention drinks in the high levy category had risen by £0.075 (£0.037-0.115, p < 0.001) per litre-a 31% pass through rate-whilst prices of intervention drinks in the low levy category and no levy category had fallen and risen by smaller amounts, respectively. Whilst the product size of branded high levy and low levy drinks barely changed after implementation of the SDIL (-7 mL [-23 to 11 mL] and 16 mL [6-27ml], respectively), there were large changes to product size of own-brand drinks with an increase of 172 mL (133-214 mL) for high levy drinks and a decrease of 141 mL (111-170 mL) for low levy drinks. The number of available drinks that were in the high levy category when the SDIL was announced was reduced by 3 (-6 to 12) by the implementation of the SDIL. Equivalent models for control drinks provided little evidence of impact of the SDIL. These results are not sales weighted, so do not give an account of how sugar consumption from drinks may have changed over the time period. CONCLUSIONS: The results suggest that the SDIL incentivised many manufacturers to reduce sugar in soft drinks. Some of the cost of the levy to manufacturers and importers was passed on to consumers as higher prices but not always on targeted drinks. These changes could reduce population exposure to liquid sugars and associated health risks.


Asunto(s)
Sacarosa en la Dieta , Bebidas Azucaradas/estadística & datos numéricos , Impuestos/legislación & jurisprudencia , Bebidas Gaseosas/legislación & jurisprudencia , Estudios Controlados Antes y Después , Costos y Análisis de Costo , Humanos , Análisis de Series de Tiempo Interrumpido , Tamaño de la Porción , Bebidas Azucaradas/legislación & jurisprudencia , Reino Unido
10.
Public Health Nutr ; 23(8): 1281-1296, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32209142

RESUMEN

OBJECTIVE: There are concerns that price promotions encourage unhealthy dietary choices. This review aims to answer the following research questions (RQ1) what is the prevalence of price promotions on foods in high-income settings, and (RQ2) are price promotions more likely to be found on unhealthy foods? DESIGN: Systematic review of articles published in English, in peer-review journals, after 1 January 2000. SETTING: Included studies measured the prevalence of price promotions (i.e. percentage of foods carrying a price promotion out of the total number of foods available to purchase) in retail settings, in upper-mid to high-income countries. PARTICIPANTS: 'Price promotion' was defined as a consumer-facing temporary price reduction or discount available to all customers. The control group/comparator was the equivalent products without promotions. The primary outcome for this review was the prevalence of price promotions, and the secondary outcome was the difference between the proportions of price promotions on healthy and unhealthy foods. RESULTS: Nine studies (239 344 observations) were included for the meta-analysis for RQ1, the prevalence of price promotions ranged from 6 % (95 % CI 2 %, 15 %) for energy-dense nutrient-poor foods to 15 % (95 % CI 9 %, 25 %) for cereals, grains, breads and other starchy carbohydrates. However, the I-squared statistic was 99 % suggesting a very high level of heterogeneity. Four studies were included for the analysis of RQ2, of which two supported the hypothesis that price promotions were more likely to be found on unhealthy foods. CONCLUSIONS: The prevalence of price promotions is very context specific, and any proposed regulations should be supported by studies conducted within the proposed setting(s).


Asunto(s)
Comercio/estadística & datos numéricos , Costos y Análisis de Costo/estadística & datos numéricos , Abastecimiento de Alimentos/estadística & datos numéricos , Alimentos/estadística & datos numéricos , Comportamiento del Consumidor , Dieta/economía , Dieta/estadística & datos numéricos , Dieta Saludable/economía , Dieta Saludable/estadística & datos numéricos , Alimentos/economía , Abastecimiento de Alimentos/economía , Humanos , Mercadotecnía/estadística & datos numéricos , Valor Nutritivo , Prevalencia
11.
Proc Biol Sci ; 286(1910): 20191502, 2019 09 11.
Artículo en Inglés | MEDLINE | ID: mdl-31506051

RESUMEN

The fish clade Pelagiaria, which includes tunas as its most famous members, evolved remarkable morphological and ecological variety in a setting not generally considered conducive to diversification: the open ocean. Relationships within Pelagiaria have proven elusive due to short internodes subtending major lineages suggestive of rapid early divergences. Using a novel sequence dataset of over 1000 ultraconserved DNA elements (UCEs) for 94 of the 286 species of Pelagiaria (more than 70% of genera), we provide a time-calibrated phylogeny for this widely distributed clade. Some inferred relationships have clear precedents (e.g. the monophyly of 'core' Stromateoidei, and a clade comprising 'Gempylidae' and Trichiuridae), but others are unexpected despite strong support (e.g. Chiasmodontidae + Tetragonurus). Relaxed molecular clock analysis using node-based fossil calibrations estimates a latest Cretaceous origin for Pelagiaria, with crown-group families restricted to the Cenozoic. Estimated mean speciation rates decline from the origin of the group in the latest Cretaceous, although credible intervals for root and tip rates are broad and overlap in most cases, and there is higher-than-expected partitioning of body shape diversity (measured as fineness ratio) between clades concentrated during the Palaeocene-Eocene. By contrast, more direct measures of ecology show either no substantial deviation from a null model of diversification (diet) or patterns consistent with evolutionary constraint or high rates of recent change (depth habitat). Collectively, these results indicate a mosaic model of diversification. Pelagiarians show high morphological disparity and modest species richness compared to better-studied fish radiations in contrasting environments. However, this pattern is also apparent in other clades in open-ocean or deep-sea habitats, and suggests that comparative study of such groups might provide a more inclusive model of the evolution of diversity in fishes.


Asunto(s)
Peces , Filogenia , Animales , Biodiversidad , Evolución Biológica , Ecosistema , Fósiles , Especiación Genética , Océanos y Mares , Atún
12.
Glob Chang Biol ; 24(3): 957-971, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29152888

RESUMEN

A consequence of climate change has been an advance in the timing of seasonal events. Differences in the rate of advance between trophic levels may result in predators becoming mismatched with prey availability, reducing fitness and potentially driving population declines. Such "trophic asynchrony" is hypothesized to have contributed to recent population declines of long-distance migratory birds in particular. Using spatially extensive survey data from 1983 to 2010 to estimate variation in spring phenology from 280 plant and insect species and the egg-laying phenology of 21 British songbird species, we explored the effects of trophic asynchrony on avian population trends and potential underlying demographic mechanisms. Species which advanced their laying dates least over the last three decades, and were therefore at greatest risk of asynchrony, exhibited the most negative population trends. We expressed asynchrony as the annual variation in bird phenology relative to spring phenology, and related asynchrony to annual avian productivity. In warmer springs, birds were more asynchronous, but productivity was only marginally reduced; long-distance migrants, short-distance migrants and resident bird species all exhibited effects of similar magnitude. Long-term population, but not productivity, declines were greatest among those species whose annual productivity was most greatly reduced by asynchrony. This suggests that population change is not mechanistically driven by the negative effects of asynchrony on productivity. The apparent effects of asynchrony on population trends are therefore either more likely to be strongly expressed via other demographic pathways, or alternatively, are a surrogate for species' sensitivity to other environmental pressures which are the ultimate cause of decline.


Asunto(s)
Cambio Climático , Pájaros Cantores/fisiología , Migración Animal , Animales , Dinámica Poblacional , Reproducción , Estaciones del Año
13.
BMC Med Educ ; 18(1): 160, 2018 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-29973203

RESUMEN

BACKGROUND: Against the background of the recruitment crisis in general practice, we aimed to determine what United Kingdom (UK) medical students value in their future careers, how they perceive careers in general practice (GP) and what influences them. METHODS: Cross-sectional survey of 280 final and penultimate year medical students at the University of Oxford, with questions relating to career choices, factors of importance when choosing a career and attitudes towards general practice as a career. Quantitative methods included cluster analysis, chi squared tests of independence and logistic regression analysis. Qualitative data were analysed thematically using the Framework method. RESULTS: Response rate was 89% (280/315). 40% of participants said that general practice was an attractive or very attractive career option. Respondents valued job satisfaction, work-life balance and close relationships with patients. However, fewer than 20% of respondents agreed that community-based working was important to them and many (often citing particular GPs they had observed) felt that general practice as currently structured may not be satisfying or fulfilling because of high workload, financial pressures and externally imposed directives. 63% perceived GPs to have lower status than hospital specialties and 49% thought the overall culture of their medical school had negatively influenced their views towards general practice. Some respondents considered that general practice would not be intellectually challenging or compatible with a research career; some appeared to have had limited exposure to academic primary care. CONCLUSIONS: With the caveat that this was a sample from a single medical school, medical students may be put off careers in general practice by three main things: low perceived value of community-based working and low status of general practice (linked to a prevailing medical school culture); observing the pressures under which GPs currently work; and lack of exposure to academic role models and primary care-based research opportunities. To improve recruitment of the next generation of GPs, medical schools must provide high quality placements in general practice, expose students to academic role models and highlight to policymakers the links between the current pressures in UK general practice and the recruitment crisis.


Asunto(s)
Actitud del Personal de Salud , Selección de Profesión , Medicina General , Estudiantes de Medicina/psicología , Estudios Transversales , Inglaterra , Femenino , Humanos , Satisfacción en el Trabajo , Masculino , Relaciones Médico-Paciente , Investigación Cualitativa , Facultades de Medicina , Encuestas y Cuestionarios , Reino Unido , Equilibrio entre Vida Personal y Laboral
14.
BMC Evol Biol ; 16(1): 224, 2016 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-27769164

RESUMEN

BACKGROUND: Flatfish cranial asymmetry represents one of the most remarkable morphological innovations among vertebrates, and has fueled vigorous debate on the manner and rate at which strikingly divergent phenotypes evolve. A surprising result of many recent molecular phylogenetic studies is the lack of support for flatfish monophyly, where increasingly larger DNA datasets of up to 23 loci have either yielded a weakly supported flatfish clade or indicated the group is polyphyletic. Lack of resolution for flatfish relationships has been attributed to analytical limitations for dealing with processes such as nucleotide non-stationarity and incomplete lineage sorting (ILS). We tackle this phylogenetic problem using a sequence dataset comprising more than 1,000 ultraconserved DNA element (UCE) loci covering 45 carangimorphs, the broader clade containing flatfishes and several other specialized lineages such as remoras, billfishes, and archerfishes. RESULTS: We present a phylogeny based on UCE loci that unequivocally supports flatfish monophyly and a single origin of asymmetry. We document similar levels of discordance among UCE loci as in previous, smaller molecular datasets. However, relationships among flatfishes and carangimorphs recovered from multilocus concatenated and species tree analyses of our data are robust to the analytical framework applied and size of data matrix used. By integrating the UCE data with a rich fossil record, we find that the most distinctive carangimorph bodyplans arose rapidly during the Paleogene (66.0-23.03 Ma). Flatfish asymmetry, for example, likely evolved over an interval of no more than 2.97 million years. CONCLUSIONS: The longstanding uncertainty in phylogenetic hypotheses for flatfishes and their carangimorph relatives highlights the limitations of smaller molecular datasets when applied to successive, rapid divergences. Here, we recovered significant support for flatfish monophyly and relationships among carangimorphs through analysis of over 1,000 UCE loci. The resulting time-calibrated phylogeny points to phenotypic divergence early within carangimorph history that broadly matches with the predictions of adaptive models of lineage diversification.


Asunto(s)
Evolución Biológica , Peces Planos/anatomía & histología , Peces Planos/genética , Animales , Peces/anatomía & histología , Peces/clasificación , Peces/genética , Peces Planos/clasificación , Fósiles , Especiación Genética , Filogenia , Análisis de Secuencia de ADN
15.
BMC Evol Biol ; 15: 109, 2015 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-26062690

RESUMEN

BACKGROUND: Antarctic notothenioids are an impressive adaptive radiation. While they share recent common ancestry with several species-depauperate lineages that exhibit a relictual distribution in areas peripheral to the Southern Ocean, an understanding of their evolutionary origins and biogeographic history is limited as the sister lineage of notothenioids remains unidentified. The phylogenetic placement of notothenioids among major lineages of perciform fishes, which include sculpins, rockfishes, sticklebacks, eelpouts, scorpionfishes, perches, groupers and soapfishes, remains unresolved. We investigate the phylogenetic position of notothenioids using DNA sequences of 10 protein coding nuclear genes sampled from more than 650 percomorph species. The biogeographic history of notothenioids is reconstructed using a maximum likelihood method that integrates phylogenetic relationships, estimated divergence times, geographic distributions and paleogeographic history. RESULTS: Percophis brasiliensis is resolved, with strong node support, as the notothenioid sister lineage. The species is endemic to the subtropical and temperate Atlantic coast of southern South America. Biogeographic reconstructions imply the initial diversification of notothenioids involved the western portion of the East Gondwanan Weddellian Province. The geographic disjunctions among the major lineages of notothenioids show biogeographic and temporal correspondence with the fragmentation of East Gondwana. CONCLUSIONS: The phylogenetic resolution of Percophis requires a change in the classification of percomorph fishes and provides evidence for a western Weddellian origin of notothenioids. The biogeographic reconstruction highlights the importance of the geographic and climatic isolation of Antarctica in driving the radiation of cold-adapted notothenioids.


Asunto(s)
Perciformes/clasificación , Perciformes/genética , Animales , Regiones Antárticas , Evolución Molecular , Proteínas de Peces/genética , Funciones de Verosimilitud , Perciformes/anatomía & histología , Filogenia , América del Sur
16.
Mol Phylogenet Evol ; 84: 158-65, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25615427

RESUMEN

Inference of evolutionary relationships among closely related darter species (Teleostei: Percidae) has traditionally proven challenging due to a lack of sufficient numbers of informative morphological characters or reliance on mtDNA sequences. These factors have contributed to longstanding uncertainty of the monophyly of many described taxonomic groups. Although multi-locus data are now available for most darter species, uncertainty has persisted regarding the relationships of some major lineages. Here, we investigate the relationships of darters classified in Goneaperca, a clade of 46 species, many of which are characterized by distinct nuptial displays and male-only parental care. Previous phylogenetic analyses of morphological and molecular data have failed to provide strong resolution of relationships among major Goneaperca subclades, and especially the monophyly of Catonotus. We apply coalescent and phylogenetic analyses to a dataset that includes intraspecific sampling for nearly all species of Goneaperca for 13 nuclear genes. Our coalescent species tree analyses resolved a strongly supported sister relationship between Boleosoma and a monophyletic Catonotus. Ancestor state reconstructions using the posterior distribution of these newly inferred phylogenies support a single origin of male-only parental care in the most recent common ancestor of Boleosoma and Catonotus.


Asunto(s)
Evolución Biológica , Comportamiento de Nidificación , Percas/clasificación , Filogenia , Animales , Teorema de Bayes , Núcleo Celular/genética , Femenino , Masculino , Modelos Genéticos , Percas/fisiología , Análisis de Secuencia de ADN
17.
Mol Phylogenet Evol ; 93: 172-9, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26265255

RESUMEN

The percomorph fish clade Gobiiformes is a worldwide, tropical and temperate radiation with species occupying nearly all aquatic, and some semi-terrestrial, habitats. Early molecular phylogenetic studies led to the discovery of Gobiiformes, which contains Gobioidei, the gobies and sleepers, and a clade (Apogonoidei) consisting of Apogonidae and Kurtus, the cardinalfishes and nurseryfishes. Gobioidei is consistently resolved as monophyletic in molecular studies, and includes eight families whose members range from waterfall climbing stream gobies to several prominent lineages inhabiting coral reefs. The sister taxon to Gobioidei is also reliably resolved as Apogonoidei. Despite the consistent support for gobiiform monophyly in molecular studies, it is not known if percomorph lineages unsampled in molecular phylogenetic studies are closely related to Gobioidei or Apogonoidei. Here we assemble a large dataset of DNA sequence from ten protein-coding genes, sampling widely across Acanthomorpha and Percomorpha, including Gobioidei, Apogonidae, and Kurtus, along with representatives of all twelve families comprising the former Trachinoidei. The phylogenies inferred from the nuclear gene sequences show that Trachinoidei is polyphyletic, with constituent lineages spread widely among several major percomorph clades. Most notably, the sanddivers (Trichonotus) are resolved as the sister lineage of Gobioidei. This study clarifies the phylogenetic relationships of lineages previously classified in Trachinoidei, identifies Trichonotus as the sister lineage of gobies, provides a molecular phylogeny of the major lineages of Gobioidei, and offers suggested changes to percomorph classification.


Asunto(s)
Peces/genética , Animales , Secuencia de Bases , Femenino , Proteínas de Peces/genética , Masculino , Filogenia , Análisis de Secuencia de ADN
18.
J Anim Ecol ; 84(1): 21-34, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25123260

RESUMEN

Aphids represent a significant challenge to food production. The Rothamsted Insect Survey (RIS) runs a network of 12·2-m suction-traps throughout the year to collect migrating aphids. In 2014, the RIS celebrated its 50th anniversary. This paper marks that achievement with an extensive spatiotemporal analysis and the provision of the first British annotated checklist of aphids since 1964. Our main aim was to elucidate mechanisms that advance aphid phenology under climate change and explain these using life-history traits. We then highlight emerging pests using accumulation patterns. Linear and nonlinear mixed-effect models estimated the average rate of change per annum and effects of climate on annual counts, first and last flights and length of flight season since 1965. Two climate drivers were used: the accumulated day degrees above 16 °C (ADD16) indicated the potential for migration during the aphid season; the North Atlantic Oscillation (NAO) signalled the severity of the winter before migration took place. All 55 species studied had earlier first flight trends at rate of ß = -0·611 ± SE 0·015 days year(-1). Of these species, 49% had earlier last flights, but the average species effect appeared relatively stationary (ß = -0·010 ± SE 0·022 days year(-1)). Most species (85%) showed increasing duration of their flight season (ß = 0·336 ± SE 0·026 days year(-1)), even though only 54% increased their log annual count (ß = 0·002 ± SE <0·001 year(-1)). The ADD16 and NAO were shown to drive patterns in aphid phenology in a spatiotemporal context. Early in the year when the first aphids were migrating, the effect of the winter NAO was highly significant. Further into the year, ADD16 was a strong predictor. Latitude had a near linear effect on first flights, whereas longitude produced a generally less-clear effect on all responses. Aphids that are anholocyclic (permanently parthenogenetic) or are monoecious (non-host-alternating) were advancing their phenology faster than those that were not. Climate drives phenology and traits help explain how this takes place biologically. Phenology and trait ecology are critical to understanding the threat posed by emerging pests such as Myzus persicae nicotianae and Aphis fabae cirsiiacanthoidis, as revealed by the species accumulation analysis.


Asunto(s)
Migración Animal , Áfidos/fisiología , Biodiversidad , Animales , Clima , Estaciones del Año , Reino Unido
19.
Curr Biol ; 34(11): 2541-2550.e4, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38788708

RESUMEN

Major ecological transitions are thought to fuel diversification, but whether they are contingent on the evolution of certain traits called key innovations1 is unclear. Key innovations are routinely invoked to explain how lineages rapidly exploit new ecological opportunities.1,2,3 However, investigations of key innovations often focus on single traits rather than considering trait combinations that collectively produce effects of interest.4 Here, we investigate the evolution of synergistic trait interactions in anglerfishes, which include one of the most species-rich vertebrate clades in the bathypelagic, or "midnight," zone of the deep sea: Ceratioidea.5 Ceratioids are the only vertebrates that possess sexual parasitism, wherein males temporarily attach or permanently fuse to females to mate.6,7 We show that the rapid transition of ancestrally benthic anglerfishes into pelagic habitats occurred during a period of major global warming 50-35 million years ago.8,9 This transition coincided with the origins of sexual parasitism, which is thought to increase the probability of successful reproduction once a mate is found in the midnight zone, Earth's largest habitat.5,6,7 Our reconstruction of the evolutionary history of anglerfishes and the loss of immune genes support that permanently fusing clades have convergently degenerated their adaptive immunity. We find that degenerate adaptive immune genes and sexual body size dimorphism, both variably present in anglerfishes outside the ceratioid radiation, likely promoted their transition into the bathypelagic zone. These results show how traits from separate physiological, morphological, and reproductive systems can interact synergistically to drive major transitions and subsequent diversification in novel environments.


Asunto(s)
Evolución Biológica , Océanos y Mares , Animales , Ecosistema , Filogenia , Masculino , Femenino
20.
PLoS One ; 19(6): e0301890, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38843248

RESUMEN

BACKGROUND: In April 2018, the UK government implemented a levy on soft drinks importers and manufacturers, tiered according to the amount of sugar in drinks. The stated aim was to encourage manufacturers to reduce sugar and portion sizes. Previous evidence suggests that the policy has been successful in reducing sugar in drinks in the short-term since implementation, but their sustained effects have not been explored. This study aimed to assess the impact of the soft drink industry levy (SDIL) on sugar levels, price, portion size and use of non-sugar sweeteners in the medium-term. METHODS AND FINDINGS: Product data from 30 November 2017 to 14 March 2020 from one major UK retail supermarket were analysed (112,452 observations, 126 weekly time points). We used interrupted time series analysis, to assess the impact of the soft-drink industry levy (SDIL) on levy-eligible soft drinks, with exempt drinks (i.e. 100% fruit juices, milks, flavoured milks) acting as a comparator series. At the point of implementation of the SDIL (April 2018) there was a step change in the proportion of eligible drinks with sugar content below the SDIL levy threshold (5g per 100ml) (+0.08, 95%CI: +0.04, +0.12), with a similar sized decrease in the proportion in the highest levy category (> = 8g sugar per 100ml) (-0.06, 95%CI: -0.10, -0.03). Between April 2018 and March 2020, the proportion of eligible drinks below the SDIL levy threshold continued to gradually increase (p = 0.003), while those in the highest levy category decreased (p = 0.007). There was a step change in price of eligible drinks in the higher levy category at the point of implementation of +£0.049 (95%CI: +£0.034, +£0.065) per 100mL (for comparison, the levy is set at £0.024 per 100mL for this group). Trends in price for the high levy category were not altered by the SDIL. In the no levy category, there was a step change in price at the implementation (+£0.012 per 100mL, 95%CI: +£0.008, +£0.023), followed by a second step change in October 2018 (-£0.018p per 100mL, 95%CI: -£0.033, -£0.001p). The volume of products in the higher levy group decreased at the time of the implementation (-305mL on average including multipacks, 95%CI: -511, -99). The change in trend for the product volume of drinks in the higher levy group between April 2018 and March 2020 was in the increasing direction (+704mL per year, 95%CI: -95, 1504), but it did not meet our threshold for statistical significance (p = 0.084). There were no changes observed in the volume of lower levy drinks or no levy drinks. There was a step change in the proportion of drinks with non-sugar sweeteners at the implementation of the SDIL (+0.04, 95%CI: +0.02, +0.06). CONCLUSION: These results suggest that the SDIL was successful in [1] producing reductions in sugar levels that were maintained over the medium term up to March 2020 and [2] a reduction in product volume for higher tier drinks that may be diminishing over time. Our results also show that the SDIL was associated with a maintained price differential between high and low sugar drinks.


Asunto(s)
Bebidas Gaseosas , Análisis de Series de Tiempo Interrumpido , Bebidas Gaseosas/economía , Reino Unido , Humanos , Comercio , Industria de Alimentos/tendencias
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