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2.
Nat Ecol Evol ; 7(3): 414-423, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36702857

RESUMO

Phenotypic plasticity in ancestral populations is hypothesized to facilitate adaptation, but evidence is piecemeal and often contradictory. Further, whether ancestral plasticity increases the probability of parallel adaptive changes has not been explored. The most general finding is that ancestral responses to a new environment are reversed following adaptation (known as reversion). We investigated the contribution of ancestral plasticity to adaptive evolution of gene expression in two independently evolved lineages of zinc-tolerant Silene uniflora. We found that the general pattern of reversion is driven by the absence of a widespread stress response in zinc-adapted plants compared with zinc-sensitive plants. We show that ancestral plasticity that moves expression closer to the optimum value in the new environment influences the evolution of gene expression among genes that are likely to be involved in adaptation and increases the chance that genes are recruited repeatedly during adaptation. However, despite convergence in gene expression levels between independently adapted lineages, ancestral plasticity does not influence how similar expression values of adaptive genes become. Surprisingly, we also observed that ancestral plasticity that increases fitness often becomes genetically determined and fixed, that is, genetically assimilated. These results emphasize the important role of ancestral plasticity in parallel adaptation.


Assuntos
Silene , Silene/genética , Evolução Biológica , Zinco , Adaptação Fisiológica , Aclimatação
3.
Science ; 378(6623): eabf0869, 2022 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-36454829

RESUMO

Madagascar's biota is hyperdiverse and includes exceptional levels of endemicity. We review the current state of knowledge on Madagascar's past and current terrestrial and freshwater biodiversity by compiling and presenting comprehensive data on species diversity, endemism, and rates of species description and human uses, in addition to presenting an updated and simplified map of vegetation types. We report a substantial increase of records and species new to science in recent years; however, the diversity and evolution of many groups remain practically unknown (e.g., fungi and most invertebrates). Digitization efforts are increasing the resolution of species richness patterns and we highlight the crucial role of field- and collections-based research for advancing biodiversity knowledge and identifying gaps in our understanding, particularly as species richness corresponds closely to collection effort. Phylogenetic diversity patterns mirror that of species richness and endemism in most of the analyzed groups. We highlight humid forests as centers of diversity and endemism because of their role as refugia and centers of recent and rapid radiations. However, the distinct endemism of other areas, such as the grassland-woodland mosaic of the Central Highlands and the spiny forest of the southwest, is also biologically important despite lower species richness. The documented uses of Malagasy biodiversity are manifold, with much potential for the uncovering of new useful traits for food, medicine, and climate mitigation. The data presented here showcase Madagascar as a unique "living laboratory" for our understanding of evolution and the complex interactions between people and nature. The gathering and analysis of biodiversity data must continue and accelerate if we are to fully understand and safeguard this unique subset of Earth's biodiversity.


Assuntos
Biodiversidade , Evolução Biológica , Humanos , Biota , Florestas , Madagáscar , Filogenia
4.
Science ; 378(6623): eadf1466, 2022 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-36454830

RESUMO

Madagascar's unique biota is heavily affected by human activity and is under intense threat. Here, we review the current state of knowledge on the conservation status of Madagascar's terrestrial and freshwater biodiversity by presenting data and analyses on documented and predicted species-level conservation statuses, the most prevalent and relevant threats, ex situ collections and programs, and the coverage and comprehensiveness of protected areas. The existing terrestrial protected area network in Madagascar covers 10.4% of its land area and includes at least part of the range of the majority of described native species of vertebrates with known distributions (97.1% of freshwater fishes, amphibians, reptiles, birds, and mammals combined) and plants (67.7%). The overall figures are higher for threatened species (97.7% of threatened vertebrates and 79.6% of threatened plants occurring within at least one protected area). International Union for Conservation of Nature (IUCN) Red List assessments and Bayesian neural network analyses for plants identify overexploitation of biological resources and unsustainable agriculture as the most prominent threats to biodiversity. We highlight five opportunities for action at multiple levels to ensure that conservation and ecological restoration objectives, programs, and activities take account of complex underlying and interacting factors and produce tangible benefits for the biodiversity and people of Madagascar.


Assuntos
Biodiversidade , Espécies em Perigo de Extinção , Animais , Humanos , Teorema de Bayes , Biota , Madagáscar , Mamíferos , Plantas
5.
Arch Dis Child Fetal Neonatal Ed ; 107(3): 303-310, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34551917

RESUMO

OBJECTIVE: Assess the impact of introducing a consensus guideline incorporating an adapted Sepsis Risk Calculator (SRC) algorithm, in the management of early onset neonatal sepsis (EONS), on antibiotic usage and patient safety. DESIGN: Multicentre prospective study SETTING: Ten perinatal hospitals in Wales, UK. PATIENTS: All live births ≥34 weeks' gestation over a 12-month period (April 2019-March 2020) compared with infants in the preceding 15-month period (January 2018-March 2019) as a baseline. METHODS: The consensus guideline was introduced in clinical practice on 1 April 2019. It incorporated a modified SRC algorithm, enhanced in-hospital surveillance, ongoing quality assurance, standardised staff training and parent education. The main outcome measure was antibiotic usage/1000 live births, balancing this with analysis of harm from delayed diagnosis and treatment, disease severity and readmissions from true sepsis. Outcome measures were analysed using statistical process control charts. MAIN OUTCOME MEASURES: Proportion of antibiotic use in infants ≥34 weeks' gestation. RESULTS: 4304 (14.3%) of the 30 105 live-born infants received antibiotics in the baseline period compared with 1917 (7.7%) of 24 749 infants in the intervention period (45.5% mean reduction). All 19 infants with culture-positive sepsis in the postimplementation phase were identified and treated appropriately. There were no increases in sepsis-related neonatal unit admissions, disease morbidity and late readmissions. CONCLUSIONS: This multicentre study provides evidence that a judicious adaptation of the SRC incorporating enhanced surveillance can be safely introduced in the National Health Service and is effective in reducing antibiotic use for EONS without increasing morbidity and mortality.


Assuntos
Sepse Neonatal , Sepse , Algoritmos , Antibacterianos/uso terapêutico , Feminino , Humanos , Lactente , Recém-Nascido , Sepse Neonatal/diagnóstico , Sepse Neonatal/tratamento farmacológico , Sepse Neonatal/epidemiologia , Gravidez , Estudos Prospectivos , Medição de Risco , Sepse/diagnóstico , Sepse/tratamento farmacológico , Sepse/epidemiologia , Medicina Estatal , País de Gales
6.
Mol Biol Evol ; 38(9): 3724-3736, 2021 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-33950261

RESUMO

The impact of human-mediated environmental change on the evolutionary trajectories of wild organisms is poorly understood. In particular, capacity of species to adapt rapidly (in hundreds of generations or less), reproducibly and predictably to extreme environmental change is unclear. Silene uniflora is predominantly a coastal species, but it has also colonized isolated, disused mines with phytotoxic, zinc-contaminated soils. To test whether rapid, parallel adaptation to anthropogenic pollution has taken place, we used reduced representation sequencing (ddRAD) to reconstruct the evolutionary history of geographically proximate mine and coastal population pairs and found largely independent colonization of mines from different coastal sites. Furthermore, our results show that parallel evolution of zinc tolerance has occurred without gene flow spreading adaptive alleles between mine populations. In genomic regions where signatures of selection were detected across multiple mine-coast pairs, we identified genes with functions linked to physiological differences between the putative ecotypes, although genetic differentiation at specific loci is only partially shared between mine populations. Our results are consistent with a complex, polygenic genetic architecture underpinning rapid adaptation. This shows that even under a scenario of strong selection and rapid adaptation, evolutionary responses to human activities (and other environmental challenges) may be idiosyncratic at the genetic level and, therefore, difficult to predict from genomic data.


Assuntos
Metais Pesados , Adaptação Fisiológica/genética , Ecótipo , Poluição Ambiental , Deriva Genética , Humanos , Metais Pesados/análise
7.
Glob Chang Biol ; 27(7): 1328-1348, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33494123

RESUMO

Urgent solutions to global climate change are needed. Ambitious tree-planting initiatives, many already underway, aim to sequester enormous quantities of carbon to partly compensate for anthropogenic CO2 emissions, which are a major cause of rising global temperatures. However, tree planting that is poorly planned and executed could actually increase CO2 emissions and have long-term, deleterious impacts on biodiversity, landscapes and livelihoods. Here, we highlight the main environmental risks of large-scale tree planting and propose 10 golden rules, based on some of the most recent ecological research, to implement forest ecosystem restoration that maximizes rates of both carbon sequestration and biodiversity recovery while improving livelihoods. These are as follows: (1) Protect existing forest first; (2) Work together (involving all stakeholders); (3) Aim to maximize biodiversity recovery to meet multiple goals; (4) Select appropriate areas for restoration; (5) Use natural regeneration wherever possible; (6) Select species to maximize biodiversity; (7) Use resilient plant material (with appropriate genetic variability and provenance); (8) Plan ahead for infrastructure, capacity and seed supply; (9) Learn by doing (using an adaptive management approach); and (10) Make it pay (ensuring the economic sustainability of the project). We focus on the design of long-term strategies to tackle the climate and biodiversity crises and support livelihood needs. We emphasize the role of local communities as sources of indigenous knowledge, and the benefits they could derive from successful reforestation that restores ecosystem functioning and delivers a diverse range of forest products and services. While there is no simple and universal recipe for forest restoration, it is crucial to build upon the currently growing public and private interest in this topic, to ensure interventions provide effective, long-term carbon sinks and maximize benefits for biodiversity and people.


Assuntos
Sequestro de Carbono , Ecossistema , Biodiversidade , Conservação dos Recursos Naturais , Florestas , Humanos , Árvores
8.
PhytoKeys ; 169: 1-59, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33354138

RESUMO

Based on extensive herbarium, field, botanical illustration, and molecular phylogenetic research, five genera and eight species are recognised for the Neotropical Haemodoraceae. New taxa include Cubanicula Hopper et al., Xiphidium pontederiiflorum M.Pell. et al. and Schiekia timida M.Pell. et al. Two new combinations are made, Cubanicula xanthorrhizos (C.Wright ex Griseb.) Hopper et al. and Schiekia silvestris (Maas & Stoel) Hopper et al. We also correct the author citation for Xiphidium, provide the necessary typifications for several names and present an updated identification key, comments, and photo plates for all species. Finally, we provide high-quality illustrations for most of the recognised species and their diagnostic characters.

9.
Arch Dis Child Fetal Neonatal Ed ; 105(2): 118-122, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31296696

RESUMO

OBJECTIVE: To compare management recommendations of the National Institute for Health and Care Excellence (NICE) guidelines with the Kaiser Permanente sepsis risk calculator (SRC) for risk of early onset neonatal sepsis (EONS). DESIGN: Multicentre prospective observational projection study. SETTING: Eight maternity hospitals in Wales, UK. PATIENTS: All live births ≥34 weeks gestation over a 3-month period (February-April 2018). METHODS: Demographics, maternal and infant risk factors, infant's clinical status, antibiotic usage and blood culture results from first 72 hours of birth were collected. Infants were managed using NICE recommendations and decisions compared with that projected by SRC. MAIN OUTCOME MEASURE: Proportion of infants recommended for antibiotics on either tool. RESULTS: Of 4992 eligible infants, complete data were available for 3593 (71.9%). Of these, 576 (16%) were started on antibiotics as per NICE recommendations compared with 156 (4.3%) projected by the SRC, a relative reduction of 74%. Of the 426 infants avoiding antibiotics, SRC assigned 314 (54.6%) to normal care only. There were seven positive blood cultures-three infants were recommended antibiotics by both, three were not identified in the asymptomatic stage by either; one was a contaminant. No EONS-related readmission was reported. CONCLUSION: The judicious adoption of SRC in UK clinical practice for screening and management of EONS could potentially reduce interventions and antibiotic usage in three out of four term or near-term infants and promote earlier discharge from hospital in >50%. We did not identify any EONS case missed by SRC when compared with NICE. These results have significant implications for healthcare resources.


Assuntos
Antibacterianos/uso terapêutico , Maternidades/estatística & dados numéricos , Sepse Neonatal/tratamento farmacológico , Sepse Neonatal/epidemiologia , Antibacterianos/efeitos adversos , Hemocultura , Feminino , Idade Gestacional , Nível de Saúde , Humanos , Recém-Nascido , Masculino , Guias de Prática Clínica como Assunto , Estudos Prospectivos , Medição de Risco , Fatores de Risco , Fatores Socioeconômicos , Medicina Estatal , País de Gales/epidemiologia
11.
Ann Bot ; 104(3): 507-16, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18940852

RESUMO

BACKGROUND AND AIMS: Species may occur over a wide geographical range within which populations can display large variation in reproductive success and genetic diversity. Neotinea maculata is a rare orchid of conservation concern at the edge of its range in Ireland, where it occurs in small populations. However, it is relatively common throughout the Mediterranean region. Here, factors that affect rarity of N. maculata in Ireland are investigated by comparing Irish populations with those found in Italy, where it is more common. METHODS: Vegetation communities, breeding system and genetic diversity were compared using three amplified fragment length polymorphism (AFLP) primer pairs in populations in Ireland and Italy. Vegetation was quantified using quadrats taken along transects in study populations, and hand pollination experiments were performed to assess reliance of N. maculata on pollinators in both Irish and Italian populations. KEY RESULTS: Neotinea maculata occupies different vegetation communities in Italian and Irish populations. Breeding system experiments show that N. maculata is 100 % autogamous, and there are no differences in fruit and seed production in selfed, outcrossed and unmanipulated plants. AFLP markers revealed that Irish and Italian populations have similar genetic diversity and are distinct from each other. CONCLUSIONS: Neotinea maculata does not suffer any negative effects of autogamous reproduction; it self-pollinates and sets seed readily in the absence of pollinators. It occupies a variety of habitats in both Ireland and Italy; however, Irish populations are small and rare and should be conserved. This could be due to climatic factors and the absence of suitable soil mycorrhizas to allow recruitment from seed.


Assuntos
Ecossistema , Flores/genética , Variação Genética , Orchidaceae/genética , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Cruzamento , Flores/ultraestrutura , Geografia , Orchidaceae/ultraestrutura , Filogenia , Análise de Componente Principal , Solo
12.
Mol Phylogenet Evol ; 51(1): 19-30, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19063982

RESUMO

Molecular phylogenetic studies of Haemodoraceae in the Greater Cape and Southwest Australian Floristic Region (SWAFR) using trnL, trnL-F and matK sequence data affirm the presence of old and young rapidly radiated lineages in both regions. Commencement of tribal and generic divergence in the subfamilies occured in the Eocene in the two regions, but subsequent patterns of radiation differ slightly. The hypothesis of rapid recent speciation in these regions from the late Pliocene as the major explanation for endemic species richness is still repeated by several contemporary authors despite increasing molecular phylogenetic evidence to the contrary. Our estimates of the age of lineages in Haemodoraceae show significant lineage turnover occurring over the last 15 million years, since the mid-Miocene, with divergence of the major clades beginning in the Eocene. The search for independent evidence to date speciation episodes reliably and investigation of molecular analyses across a broad spectrum of these clades must be pursued to advance ideas rigorously concerning origins of species richness. These regions continue to confound attempts to develop theory concerning origins of global species richness, with consequent implications for conservation biology.


Assuntos
Evolução Molecular , Magnoliopsida/genética , Filogenia , África Austral , Teorema de Bayes , DNA de Plantas/genética , Especiação Genética , Magnoliopsida/classificação , Análise de Sequência de DNA , Especificidade da Espécie
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