8 research outputs found

    Conservation of oceanic island floras: Present and future global challenges

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    Currentthreatstotheplanet’sbiodiversityareunprecedented,andtheyparticularlyimperilinsular floras.Inthisinvestigation,weusethethreatfactorsidentifiedbytheMillenniumEcosystem Assessmentasthemaindriversofbiodiversitylossonislandstodefineandrank13current,continuing threatstotheplantdiversityofninefocalarchipelagoswherevolcanicorigin(orintheSeychellesa prolongedisolationafteracontinentalorigin)hasproducedahighdegreeofendemicityandfragilityin the faceofhabitatalteration.Wealsoconductaglobalendangermentassessmentbasedonthe numbersofinsularendemicplantsintheendangered(EN)andcriticallyendangered(CR)IUCN categoriesfor53islandgroupswithanestimated9951endemicplantspecies,providinga representativesampleoftheworld’sinsularsystemsandtheirfloristicrichness.Ouranalysesindicate that isolationdoesnotsignificantlyinfluenceendangerment,butplantendemicsfromverysmall islandsaremoreoftencriticallyendangered.Weestimatethatbetween3500and6800oftheestimated 70,000 insularendemicplantspeciesworldwidemightbehighlythreatened(CR+EN)andbetweenca. 2000 and2800ofthemincriticaldangerofextinction(CR).Basedontheseanalyses,andona worldwideliteraturereviewofthebiologicalthreatfactorsconsidered,weidentifychallenging questionsforconservationresearch,asking(i)whatarethemosturgentprioritiesfortheconservation of insularspeciesandfloras,and(ii)withtheknowledgeandassetsavailable,howcanweimprovethe impactofconservationscienceandpracticeonthepreservationofislandbiodiversity?Ouranalysis indicatesthatthesynergisticactionofmanythreatfactorscaninducemajorecologicaldisturbances, leadingtomultipleextinctions.Wereviewweaknessesandstrengthsinconservationresearchand managementintheninefocalarchipelagos,andhighlighttheurgentneedforconservationscientiststo shareknowledgeandexpertise,identifyanddiscusscommonchallenges,andformulatemulti- disciplinaryconservationobjectivesforinsularplantendemicsworldwide.Toourknowledge,thisisthe mostup-to-dateandcomprehensivesurveyyettoreviewthethreatfactorstonativeplantsonoceanic islandsanddefinepriorityresearchquestions

    Molecular support for a basal grade of morphologically distinct, monotypic genera in the species-rich Vanguerieae alliance (Rubiaceae, Ixoroideae) : Its systematic and conservation implications

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    Many monotypic genera with unique apomorphic characters have been difficult to place in the morphology-based classifications of the coffee family (Rubiaceae). We rigorously assessed the subfamilial phylogenetic position and generic status of three enigmatic genera, the Seychellois Glionnetia, the Southeast Asian Jackiopsis, and the Chinese Trailliaedoxa within Rubiaceae, using sequence data of four plastid markers (ndhF, rbcL, rps16, trnT-F). The present study provides molecular phylogenetic support for positions of these genera in the subfamily Ixoroideae, and reveals the presence of a basal grade of morphologically distinct, monotypic genera (Crossopteryx,Jackiopsis,Scyphiphora,Trailliaedoxa, and Glionnetia, respectively) in the species-rich Vanguerieae alliance. These five genera may represent sole representatives of their respective lineages and therefore may carry unique genetic information. Their conservation status was assessed, applying the criteria set in IUCN Red List Categories. We consider Glionnetia and Jackiopsis Endangered. Scyphiphora is recognized as Near Threatened despite its extensive range and Crossopteryx as Least Concern. Trailliaedoxa is poorly known (Data Deficient). Finally, the generic status of Glionnetia,Jackiopsis, and Trailliaedoxa and the monogeneric tribe Jackieae as defined by Ridsdale are supported.authorCount :

    Mycorrhizal symbionts of Pisonia grandis

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    Genomic reconstruction of the SARS-CoV-2 epidemic in England

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    AbstractThe evolution of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus leads to new variants that warrant timely epidemiological characterization. Here we use the dense genomic surveillance data generated by the COVID-19 Genomics UK Consortium to reconstruct the dynamics of 71 different lineages in each of 315 English local authorities between September 2020 and June 2021. This analysis reveals a series of subepidemics that peaked in early autumn 2020, followed by a jump in transmissibility of the B.1.1.7/Alpha lineage. The Alpha variant grew when other lineages declined during the second national lockdown and regionally tiered restrictions between November and December 2020. A third more stringent national lockdown suppressed the Alpha variant and eliminated nearly all other lineages in early 2021. Yet a series of variants (most of which contained the spike E484K mutation) defied these trends and persisted at moderately increasing proportions. However, by accounting for sustained introductions, we found that the transmissibility of these variants is unlikely to have exceeded the transmissibility of the Alpha variant. Finally, B.1.617.2/Delta was repeatedly introduced in England and grew rapidly in early summer 2021, constituting approximately 98% of sampled SARS-CoV-2 genomes on 26 June 2021.</jats:p
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