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Richard M K Saunders - One of the best experts on this subject based on the ideXlab platform.
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out of africa dispersal of tropical floras during the miocene climatic optimum evidence from Uvaria annonaceae
Journal of Biogeography, 2012Co-Authors: Linlin Zhou, Daniel C Thomas, Richard M K SaundersAbstract:Aim African–Asian disjunctions are common in palaeotropical taxa, and are typically explained by reference to three competing hypotheses: (1) ‘rafting’ on the Indian tectonic plate, enabling Africa-to-Asia dispersal; (2) migration via Eocene boreotropical forests; and (3) transoceanic long-distance dispersal. These hypotheses are tested using Uvaria (Annonaceae), which is distributed in tropical regions of Africa, Asia and Australasia. Recent phylogenetic reconstructions of the genus show a clear correlation with geographical provenance, indicating a probable origin in Africa and subsequent dispersal to Asia and then Australasia. Ancestral areas and migration routes are inferred and compared with estimates of divergence times in order to distinguish between the prevailing dispersal hypotheses. Location Palaeotropics. Methods Divergence times in Uvaria are estimated by analysing the sequences of four DNA regions (matK, psbA–trnH spacer, rbcL and trnL–F) from 59 Uvaria species and 77 outgroup species, using a Bayesian uncorrelated lognormal (UCLD) relaxed molecular clock. The ancestral area of Uvaria and subsequent dispersal routes are inferred using statistical dispersal–vicariance analysis (s-diva). Results Uvaria is estimated to have originated in continental Africa 31.6 Ma [95% highest posterior density (HPD): 38.4–25.1 Ma] between the Middle Eocene and Late Oligocene. Two main migration events during the Miocene are identified: dispersal into Madagascar around 17.0 Ma (95% HPD: 22.3–12.3 Ma); and dispersal into Asia between 21.4 Ma (95% HPD: 26.7–16.7 Ma) and 16.1 Ma (95% HPD: 20.1–12.1 Ma). Main conclusions Uvaria fruits are widely reported to be consumed by primates, and are therefore unlikely candidates for successful long-distance transoceanic dispersal. The other biogeographical hypotheses, involving rafting on the Indian tectonic plate, and dispersal via the European boreotropical forests associated with the Eocene thermal maximum, can be discounted due to incongruence with the divergence time estimates. An alternative scenario is suggested, involving dispersal across Arabia and central Asia via the tropical forests that developed during the late Middle Miocene thermal maximum (17–15 Ma), associated with the ‘out-of-Africa’ dispersal of primates. The probable route and mechanism of overland dispersal between Africa and Asia for tropical plant groups during the Miocene climatic optimum are clarified based on the Uvaria data.
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molecular phylogenetics of Uvaria annonaceae relationships with balonga dasoclema and australian species of melodorum
Botanical Journal of the Linnean Society, 2010Co-Authors: Linlin Zhou, Piya Chalermglin, Richard M K SaundersAbstract:An extended molecular phylogenetic analysis of Uvaria (Annonaceae) is presented, using maximum parsimony, maximum likelihood and Bayesian methods, based on sequences of four plastid DNA regions (matK, psbA-trnH spacer, rbcL and trnL-F). The additional taxa include the monotypic West African genus Balonga, the monotypic South-East Asian genus Dasoclema and seven Australian representatives of the genus Melodorum. The results indicate that all of these taxa are nested within a well-supported clade otherwise consisting of Uvaria species, indicating that their taxonomic treatment needs to be reassessed. The distinguishing morphological characteristics of the taxa are re-evaluated and interpreted as specialized adaptations of the basic Uvaria structure. The genus Uvaria is accordingly extended following the transfer of these species, necessitating six new nomenclatural combinations and two replacement names. © 2010 The Linnean Society of London, Botanical Journal of the Linnean Society, 2010, 163, 33-43.
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molecular phylogenetic support for a broader delimitation of Uvaria annonaceae inclusive of anomianthus cyathostemma ellipeia ellipeiopsis and rauwenhoffia
Systematics and Biodiversity, 2009Co-Authors: Linlin Zhou, Richard M K SaundersAbstract:Abstract Uvaria (Annonaceae), a large palaeotropical genus of woody climbers, closely resembles several other smaller genera, including Anomianthus, Cyathostemma, Ellipeia, Ellipeiopsis and Rauwenhoffia. A molecular phylogenetic analysis of this group was undertaken using maximum parsimony, maximum likelihood and Bayesian methods based on four chloroplast DNA regions (matK, psbA‐trnH spacer, rbcL and trnL‐F). The resultant trees were moderately well resolved with significant statistical support for most nodes. Uvaria is shown unequivocally to be paraphyletic, with all representatives of the other five genera nested within it. The distinguishing morphological characteristics of the related genera are re‐evaluated, and interpreted as no more than specialised adaptations of the basic Uvaria structure. The generic names Anomianthus, Cyathostemma, Ellipeia, Ellipeiopsis and Rauwenhoffia are accordingly reduced to synonymy with Uvaria, necessitating 11 new nomenclatural combinations and four replacement names.
Linlin Zhou - One of the best experts on this subject based on the ideXlab platform.
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out of africa dispersal of tropical floras during the miocene climatic optimum evidence from Uvaria annonaceae
Journal of Biogeography, 2012Co-Authors: Linlin Zhou, Daniel C Thomas, Richard M K SaundersAbstract:Aim African–Asian disjunctions are common in palaeotropical taxa, and are typically explained by reference to three competing hypotheses: (1) ‘rafting’ on the Indian tectonic plate, enabling Africa-to-Asia dispersal; (2) migration via Eocene boreotropical forests; and (3) transoceanic long-distance dispersal. These hypotheses are tested using Uvaria (Annonaceae), which is distributed in tropical regions of Africa, Asia and Australasia. Recent phylogenetic reconstructions of the genus show a clear correlation with geographical provenance, indicating a probable origin in Africa and subsequent dispersal to Asia and then Australasia. Ancestral areas and migration routes are inferred and compared with estimates of divergence times in order to distinguish between the prevailing dispersal hypotheses. Location Palaeotropics. Methods Divergence times in Uvaria are estimated by analysing the sequences of four DNA regions (matK, psbA–trnH spacer, rbcL and trnL–F) from 59 Uvaria species and 77 outgroup species, using a Bayesian uncorrelated lognormal (UCLD) relaxed molecular clock. The ancestral area of Uvaria and subsequent dispersal routes are inferred using statistical dispersal–vicariance analysis (s-diva). Results Uvaria is estimated to have originated in continental Africa 31.6 Ma [95% highest posterior density (HPD): 38.4–25.1 Ma] between the Middle Eocene and Late Oligocene. Two main migration events during the Miocene are identified: dispersal into Madagascar around 17.0 Ma (95% HPD: 22.3–12.3 Ma); and dispersal into Asia between 21.4 Ma (95% HPD: 26.7–16.7 Ma) and 16.1 Ma (95% HPD: 20.1–12.1 Ma). Main conclusions Uvaria fruits are widely reported to be consumed by primates, and are therefore unlikely candidates for successful long-distance transoceanic dispersal. The other biogeographical hypotheses, involving rafting on the Indian tectonic plate, and dispersal via the European boreotropical forests associated with the Eocene thermal maximum, can be discounted due to incongruence with the divergence time estimates. An alternative scenario is suggested, involving dispersal across Arabia and central Asia via the tropical forests that developed during the late Middle Miocene thermal maximum (17–15 Ma), associated with the ‘out-of-Africa’ dispersal of primates. The probable route and mechanism of overland dispersal between Africa and Asia for tropical plant groups during the Miocene climatic optimum are clarified based on the Uvaria data.
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molecular phylogenetics of Uvaria annonaceae relationships with balonga dasoclema and australian species of melodorum
Botanical Journal of the Linnean Society, 2010Co-Authors: Linlin Zhou, Piya Chalermglin, Richard M K SaundersAbstract:An extended molecular phylogenetic analysis of Uvaria (Annonaceae) is presented, using maximum parsimony, maximum likelihood and Bayesian methods, based on sequences of four plastid DNA regions (matK, psbA-trnH spacer, rbcL and trnL-F). The additional taxa include the monotypic West African genus Balonga, the monotypic South-East Asian genus Dasoclema and seven Australian representatives of the genus Melodorum. The results indicate that all of these taxa are nested within a well-supported clade otherwise consisting of Uvaria species, indicating that their taxonomic treatment needs to be reassessed. The distinguishing morphological characteristics of the taxa are re-evaluated and interpreted as specialized adaptations of the basic Uvaria structure. The genus Uvaria is accordingly extended following the transfer of these species, necessitating six new nomenclatural combinations and two replacement names. © 2010 The Linnean Society of London, Botanical Journal of the Linnean Society, 2010, 163, 33-43.
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molecular phylogenetic support for a broader delimitation of Uvaria annonaceae inclusive of anomianthus cyathostemma ellipeia ellipeiopsis and rauwenhoffia
Systematics and Biodiversity, 2009Co-Authors: Linlin Zhou, Richard M K SaundersAbstract:Abstract Uvaria (Annonaceae), a large palaeotropical genus of woody climbers, closely resembles several other smaller genera, including Anomianthus, Cyathostemma, Ellipeia, Ellipeiopsis and Rauwenhoffia. A molecular phylogenetic analysis of this group was undertaken using maximum parsimony, maximum likelihood and Bayesian methods based on four chloroplast DNA regions (matK, psbA‐trnH spacer, rbcL and trnL‐F). The resultant trees were moderately well resolved with significant statistical support for most nodes. Uvaria is shown unequivocally to be paraphyletic, with all representatives of the other five genera nested within it. The distinguishing morphological characteristics of the related genera are re‐evaluated, and interpreted as no more than specialised adaptations of the basic Uvaria structure. The generic names Anomianthus, Cyathostemma, Ellipeia, Ellipeiopsis and Rauwenhoffia are accordingly reduced to synonymy with Uvaria, necessitating 11 new nomenclatural combinations and four replacement names.
Patera Akbar - One of the best experts on this subject based on the ideXlab platform.
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OPTIMALISASI PENGGUNAAN ALAT PELINDUNG DIRI DALAM KEGIATAN TRUCKING PT. VARIA USHA BAHARI DI PELABUHAN SEMEN INDONESIA TUBAN
2018Co-Authors: Patera AkbarAbstract:Akbar Patera, NIT. 51145524.K, 2018 “Optimalisasi Penggunaan Alat Pelindung Diri Dalam Kegiatan Trucking PT. Varia Usaha Bahari Di Pelabuhan Semen Indonesia Tuban”, Program Diploma IV, Ketatalaksanaan Angkutan Laut dan Kepelabuhanan, Politeknik Ilmu Pelayaran Semarang, Pembimbing I: Sri Suyanti, S.S dan Pembimbing II: Capt. Agus Hadi Purwantomo M.Mar Perusahaan PT. Varia Usaha Bahari adalah perusahaan bongkar muat (Stevedoring Company) yang salah satu kegiatannya adalah kegiatan Trucking. Dalam kegiatan Trucking kebanyakan pekerja tidak menggunakan fasilitas keselamatan seperti tidak memakai Safety Helmet atau alat keselamatan yang lain. Penelitian ini untuk mengetahui pemakaian alat pelindung diri dalam kegiatan Trucking PT. Varia Usaha Bahari di pelabuhan Semen Indonesia Tuban. Dalam skripsi ini, metode penelitian yang digunakan adalah metode kualitatif deskriptif yaitu untuk menggambarkan dan menguraikan obyek yang diteliti serta metode pengumpulan data yang digunakan adalah pngamatan lapangan, wawancara langsung kepada kepala cabang dan kepala operasional Trucking PT. Varia Usaha Bahari serta menggunakan studi pustaka. Adapun masalah yang paling sering terjadi pada kegiatan Trucking PT. Varia Usaha Bahari adalah penggunaan alat pelindung diri pada pekerja yang tidak sesuai dengan prosedur dan kurangnya keatuhan serta pengetahuan tentang pentingnya penggunaan alat pelindung diri. Upaya yang dilakukan PT. Varia Usaha bahari yaitu dengan melakukan penyuluhan kepada pekerja tentang pentingnya alat pelindung diri dan dengan meningkatkan kesadaran akan bahaya kecelakaan kerja. Jika penggunaan alat pelindung diri dilakukan sebagaimana mestinya setidaknya dapat mengurangi resiko kecelakaan kerja. Kata Kunci : Alat Pelindung Diri, Truckin
Akbar Patera - One of the best experts on this subject based on the ideXlab platform.
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Optimalisasi Penggunaan Alat Pelindung Diri Dalam Kegiatan Trucking PT. Varia Usaha Bahari Di Pelabuhan Semen Indonesia Tuban
2018Co-Authors: Akbar PateraAbstract:Perusahaan PT. Varia Usaha Bahari adalah perusahaan bongkar muat (Stevedoring Company) yang salah satu kegiatannya adalah kegiatan Trucking. Dalam kegiatan Trucking kebanyakan pekerja tidak menggunakan fasilitas keselamatan seperti tidak memakai Safety Helmet atau alat keselamatan yang lain. Penelitian ini untuk mengetahui pemakaian alat pelindung diri dalam kegiatan Trucking PT. Varia Usaha Bahari di pelabuhan Semen Indonesia Tuban. Dalam penelitian ini, metode penelitian yang digunakan adalah metode kualitatif deskriptif yaitu untuk menggambarkan dan menguraikan obyek yang diteliti serta metode pengumpulan data yang digunakan adalah pengamatan lapangan, wawancara langsung kepada kepala cabang dan kepala operasional Trucking PT. Varia Usaha Bahari serta menggunakan studi pustaka. Adapun masalah yang paling sering terjadi pada kegiatan Trucking PT. Varia Usaha Bahari adalah penggunaan alat pelindung diri pada pekerja yang tidak sesuai dengan prosedur dan kurangnya kepatuhan serta pengetahuan tentang pentingnya penggunaan alat pelindung diri. Upaya yang dilakukan PT. Varia Usaha bahari yaitu dengan melakukan penyuluhan kepada pekerja tentang pentingnya alat pelindung diri dan dengan meningkatkan kesadaran akan bahaya kecelakaan kerja. Jika penggunaan alat pelindung diri dilakukan sebagaimana mestinya setidaknya dapat mengurangi resiko kecelakaan kerja. Kata kunci : Alat Pelindung Diri, Truckin
Su Ycf - One of the best experts on this subject based on the ideXlab platform.
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Molecular phylogenetics of Uvaria (Annonaceae): Relationships with Balonga, Dasoclema and Australian species of Melodorum
'Wiley', 2010Co-Authors: Saunders Rmk, Zhou L, Chalermglin P, Su YcfAbstract:An extended molecular phylogenetic analysis of . Uvaria (Annonaceae) is presented, using maximum parsimony, maximum likelihood and Bayesian methods, based on sequences of four plastid DNA regions (matK, psbA-trnH spacer, rbcL and trnL-F). The additional taxa include the monotypic West African genus Balonga, the monotypic South-East Asian genus Dasoclema and seven Australian representatives of the genus Melodorum. The results indicate that all of these taxa are nested within a well-supported clade otherwise consisting of Uvaria species, indicating that their taxonomic treatment needs to be reassessed. The distinguishing morphological characteristics of the taxa are re-evaluated and interpreted as specialized adaptations of the basic Uvaria structure. The genus Uvaria is accordingly extended following the transfer of these species, necessitating six new nomenclatural combinations and two replacement names. © 2010 The Linnean Society of London.link_to_subscribed_fulltex
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Molecular phylogenetic support for a broader delimitation of Uvaria (Annonaceae), inclusive of Anomianthus, Cyathostemma, Ellipeia, Ellipeiopsis and Rauwenhoffia
'Cambridge University Press (CUP)', 2009Co-Authors: Saunders Rmk, Zhou L, Su YcfAbstract:Uvaria (Annonaceae), a large palaeotropical genus of woody climbers, closely resembles several other smaller genera, including Anomianthus, Cyathostemma, Ellipeia, Ellipeiopsis and Rauwenhoffia. A molecular phylogenetic analysis of this group was undertaken using maximum parsimony, maximum likelihood and Bayesian methods based on four chloroplast DNA regions (matK, psbA-trnH spacer, rbcL and trnL-F). The resultant trees were moderately well resolved with significant statistical support for most nodes. Uvaria is shown unequivocally to be paraphyletic, with all representatives of the other five genera nested within it. The distinguishing morphological characteristics of the related genera are re-evaluated, and interpreted as no more than specialised adaptations of the basic Uvaria structure. The generic names Anomianthus, Cyathostemma, Ellipeia, Ellipeiopsis and Rauwenhoffia are accordingly reduced to synonymy with Uvaria, necessitating 11 new nomenclatural combinations and four replacement names. © The Natural History Museum 2009.link_to_subscribed_fulltex
