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On the utility of female genitalia in the systematics of Curculionidae: examples from Entimini and Hylobiina (Coleoptera : Curculionidae)

GAIGER, Fabio; VANIN, Sergio Antonio
Fonte: SOC ENTOMOLOGIQUE FRANCE Publicador: SOC ENTOMOLOGIQUE FRANCE
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
36.71%
The utility of the female genitalia and associated sclerites (tergite and sternite VIII) in the systematics of the Curculionidae is discussed. Examples from the tribe Entimini (Entiminae) and subtribe Hylobiina (Molytinae: Hylobiini) are given. The female characters prove to be informative for establishing the phylogenetic relationships among genera of Entimini. They are essential in determining species groups within the genus Amiticus Pascoe, Hylobiina.

Re-Os isotope and highly siderophile element systematics of the Parana continental flood basalts (Brazil)

Rocha-Junior, Eduardo R. V.; Puchtel, Igor S.; Marques, Leila S.; Walker, Richard J.; Machado, Fabio B.; Nardy, Antonio J. R.; Babinski, Marly; Figueiredo, Ana M. G.
Fonte: ELSEVIER SCIENCE BV; AMSTERDAM Publicador: ELSEVIER SCIENCE BV; AMSTERDAM
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
36.71%
Basalts of the Parana continental flood basalt (PCFB) province erupted through dominantly Proterozoic continental crust during the Cretaceous. In order to examine the mantle source(s) of this major flood basalt province, we studied Os, Sr, Nd, and Pb isotope systematics, and highly siderophile element (HSE) abundances in tholeiitic basalts that were carefully chosen to show the minimal effects of crustal contamination. These basalts define a precise Re-Os isochron with an age of 131.6 +/- 2.3 Ma and an initial Os-187/Os-188 of 0.1295 +/- 0.0018 (gamma Os-187 = +2.7 +/- 1.4). This initial Os isotopic composition is considerably more radiogenic than estimates of the contemporary Depleted Mantle (DM). The fact that the Re-Os data define a well constrained isochron with an age similar to Ar-40/Ar-39 age determinations, despite generally low Os concentrations, is consistent with closed-system behavior for the HSE. Neodymium, Sr, and Pb isotopic data suggest that the mantle source of the basalts had been variably hybridized by melts derived from enriched mantle components. To account for the combined Os, Nd, Sr, and Pb isotopic characteristics of these rocks, we propose that the primary melts formed from metasomatized asthenospheric mantle (represented by arc-mantle peridotite) that underwent mixing with two enriched components...

Sistemática e filosofia: filogenia do complexo Ocotea e revisão do grupo Ocotea indecora (Lauraceae); Systematics and philosophy: phylogeny of Ocotea complex and revision of Ocotea indecora group (Lauraceae)

Assis, Leandro Cézanne de Souza
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 21/05/2009 PT
Relevância na Pesquisa
36.99%
Abordagens como homologia, construção de táxons e reconstrução da filogenia podem ser contextualizadas e investigadas por meio de uma conexão histórica e atual entre sistemática e filosofia. A presente tese defende essa conexão científico-filosófica, tendo como estudo de caso ambos o complexo Ocotea, que abrange 13 gêneros e 750 espécies predominantemente neotropicais, e o grupo Ocotea indecora, com 20 espécies e centro de diversidade na floresta atlântica do sudeste do Brasil. O capítulo 1 discute a conceitualização de táxons e homologias (táxica e transformativa) como ambos indivíduos e espécies naturais (ou agrupamentos de espécies com propriedade homeostática). Embora essas conceitualizações não sejam mutuamente exclusivas metafisicamente, a perspectiva das espécies naturais é defendida, enquanto a dos indivíduos desafiada, com base em uma motivação por aspectos empírico-pragmáticos e teórico-explicativos em sistemática e evolução. O capítulo 2 foca no renascimento da morfologia na sistemática filogenética, com base em duas teorias da verdade em epistemologia, i.e., coerência e correspondência, chamando para a unificação de ambas a teorias partir de uma teoria funderentista de justificação epistêmica das hipóteses de relação filogenética. O papel e o significado da morfologia também são discutidos no contexto de análises separadas e combinadas...

Sistemática molecular e biogeografia histórica do gênero Aratinga (Psittacidae, Aves); Molecular systematics and historical biogeography of genus Aratinga (Psittacidae, Aves)

Freddi, André Murilo Magro
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 16/04/2012 PT
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A família Psittacidae possui 332 espécies de papagaios, periquitos e afins, e os táxons Neotropicais formam um grupo monofilético (tribo Arini), dentro desta tribo está o gênero Aratinga. A sistemática deste gênero é mal resolvida, com poucos estudos morfológicos e algumas filogenias moleculares que apontam que não seja monofilético. Porém, é preciso destacar que esses estudos não amostraram uma quantidade representativa de espécies do gênero, o que deixa essas relações incertas. Para melhor compreender a história evolutiva do gênero Aratinga, realizamos uma análise filogenética com 21 das 22 espécies do gênero, o táxon monotípico Nandayus nenday que é proximamente relacionado a algumas espécies de Aratinga e representantes de outros gêneros da tribo Arini. Foram sequenciados cinco genes mitocondriais (12S, 16S, citocromo b, NADH2, COIII) e um nuclear (RAG-1). As filogenias obtidas por máxima verossimilhança e análise Bayesiana foram congruentes e indicam a ausência de monofilia do gênero Aratinga. A maioria das espécies do gênero foi posicionada em três clados com alto suporte, mas que não se apresentam agrupados em um clado monofilético. Estes três clados são congruentes com grupos previamente propostos com base em caracteres morfológicos. Nandayus nenday está dentro de um destes clados...

Re-Os isotope and highly siderophile element systematics of the Parana continental flood basalts (Brazil)

Rocha-Junior, Eduardo R. V.; Puchtel, Igor S.; Marques, Leila S.; Walker, Richard J.; Machado, Fabio B.; Nardy, Antonio J. R.; Babinski, Marly; Figueiredo, Ana M. G.
Fonte: Elsevier B.V. Publicador: Elsevier B.V.
Tipo: Artigo de Revista Científica Formato: 164-173
ENG
Relevância na Pesquisa
36.71%
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Basalts of the Parana continental flood basalt (PCFB) province erupted through dominantly Proterozoic continental crust during the Cretaceous. In order to examine the mantle source(s) of this major flood basalt province, we studied Os, Sr, Nd, and Pb isotope systematics, and highly siderophile element (HSE) abundances in tholeiitic basalts that were carefully chosen to show the minimal effects of crustal contamination. These basalts define a precise Re-Os isochron with an age of 131.6 +/- 2.3 Ma and an initial Os-187/Os-188 of 0.1295 +/- 0.0018 (gamma Os-187 = +2.7 +/- 1.4). This initial Os isotopic composition is considerably more radiogenic than estimates of the contemporary Depleted Mantle (DM). The fact that the Re-Os data define a well constrained isochron with an age similar to Ar-40/Ar-39 age determinations, despite generally low Os concentrations, is consistent with closed-system behavior for the HSE. Neodymium, Sr, and Pb isotopic data suggest that the mantle source of the basalts had been variably hybridized by melts derived from enriched mantle components. To account for the combined Os...

New Strategies on Molecular Biology Applied to Microbial Systematics

HÖFLING,José F.; ROSA,Edvaldo A. R.; BAPTISTA,Mirian J.; SPOLIDÓRIO,Denise M. P.
Fonte: Instituto de Medicina Tropical Publicador: Instituto de Medicina Tropical
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/11/1997 EN
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Systematics is the study of diversity of the organisms and their relationships comprising classification, nomenclature and identification. The term classification or taxonomy means the arrangement of the organisms in groups (rate) and the nomenclature is the attribution of correct international scientific names to organisms and identification is the inclusion of unknown strains in groups derived from classification. Therefore, classification for a stable nomenclature and a perfect identification are required previously. The beginning of the new bacterial systematics era can be remembered by the introduction and application of new taxonomic concepts and techniques, from the 50’s and 60’s. Important progress were achieved using numerical taxonomy and molecular taxonomy. Molecular taxonomy, brought into effect after the emergence of the Molecular Biology resources, provided knowledge that comprises systematics of bacteria, in which occurs great evolutionary interest, or where is observed the necessity of eliminating any environmental interference. When you study the composition and disposition of nucleotides in certain portions of the genetic material, you study searching their genome, much less susceptible to environmental alterations than proteins...

Parasite systematics in the 21st century: opportunities and obstacles

Brooks,Daniel R
Fonte: Instituto Oswaldo Cruz, Ministério da Saúde Publicador: Instituto Oswaldo Cruz, Ministério da Saúde
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2000 EN
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Thanks to the phylogenetic systematics revolution, systematic parasitology is poised to make significant contributions in tropical medicine and public health, biodiversity science, and evolutionary biology. At the same time, the taxonomic impediment is acute within parasitology. Both systematists and non-systematists must be interested in working towards common goals and establishing collaborative efforts in order to re-vitalize and re-populate systematic parasitology.

Multilocus enzyme electrophoresis: a valuable technique for providing answers to problems in parasite systematics

Andrews, Ross Hector; Chilton, Neil B.
Fonte: Elsevier Science Publicador: Elsevier Science
Tipo: Artigo de Revista Científica
Publicado em //1999 EN
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The aim of this review is to highlight the effectiveness of the technique of multilocus enzyme electrophoresis in answering questions relating to the systematics of parasites and to highlight errors in the way the technique has been used and the results interpreted. We have approached this topic by answering specific questions that we have been asked by colleagues and students not necessarily familiar with the technique, the method of data analysis and its application. Although the technique has been applied to provide answers for taxonomic and population genetics studies, it remains under-utilised, perhaps because of recent advances in newer molecular technology. Rather than not acknowledge or dismiss the value of more traditional technology, we suggest that researchers examine problems in the systematic of parasites by the comparison of data derived from morphological, biochemical and molecular techniques.; http://www.sciencedirect.com/science/journal/00207519; Copyright © 1999 Elsevier Science B.V. All rights reserved.

Molecular systematics and conservation genetics of gliding petaurids (Marsupialia: petauridae).

Malekian, Mansoureh
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado
Publicado em //2007
Relevância na Pesquisa
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The gliding petaurids are small sized arboreal and nocturnal marsupials restricted to Australia and the New Guinean region. They have suffered range contractions since European settlement, and most of the species are of conservation concern, either nationally or at a state level. This study applied molecular approaches to investigate several questions involving Petaurus species which may provide valuable insights for their conservation and management of species. The objectives of this study included an examination of phylogenetic and evolutionary relationships among Petaurus species, an assessment of phylogeographic structure within P. breviceps and an investigation of genetic diversity, social structure and mating system of P. breviceps in fragmented habitats. A broad molecular systematics study of the genus Petaurus was first undertaken. Two mitochondrial genes (ND2 and ND4) and a nuclear gene marker (ω-globin) were screened for sequence variation in samples obtained from across the distribution of petaurid species, including Australia, New Guinea and its surrounding islands. Phylogenetic analyses confirmed the monophyly of the genus Petaurus and revealed that, with the exception of P. gracilis, the currently recognised species were associated with divergent mtDNA clades. It also revealed considerable mtDNA diversity within the widely distributed species P. breviceps. The existence of at least seven distinct and divergent mtDNA lineages within P. breviceps was supported...

Systematics and diversity of Australian pygopodoid geckos (Pygopodoidea, Gekkota, Squamata).

Oliver, Paul M.
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado
Publicado em //2010
Relevância na Pesquisa
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Lizards and snakes (squamates) are the most diverse endemic component of the Australian terrestrial vertebrate fauna; and three families of Pygopodoid gecko (Carphodactylidae, Diplodactylidae and Pygopodidae) together comprise the third most species rich squamate lineage within Australia. In this thesis I present the results of an analysis of the systematics and species diversity of components of the Australian pygopodoid gecko radation; specifically, I focus on establishing an overall systematic and temporal framework for the evolution of the entire clade, examining estimates of species diversity and interrelationships within three genera, and using the resultant phylogenetic framework to advance our understanding of how the onset and expansion of aridification across Australia may have affected evolution with this lineage. In chapter two the phylogenetic relationships of all Australian pygopodoid genera (except Orraya) are examined, and temporal scale for their diversification is estimated based on Bayesian and Likelihood analyses of two nuclear genes. This work demonstrates that at least five extant lineages within this radiation diverged before the final separation of Australia from Antarctica, and that the clade has a long history within Australia equivalent to famous Gondwanan elements of the fauna...

Systematics and phylogeny of Cheloninae (Hymenoptera: Braconidae) with an emphasis on Australian species.

Kittel, Rebecca
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado
Publicado em //2014
Relevância na Pesquisa
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This study explores the systematics of the genera of Cheloninae (Hymenoptera: Braconidae) and presents a number of taxonomic revisions of Australian species. The phylogenetic relationships of the world genera were analysed by applying molecular phylogenetic analyses (based on three markers: CO1, 28S and ef1α, totalling 1454 bp of sequenced data) combined with morphological data. The results show that most genera are monophyletic, although the current tribes were not. Also the previously recognised subgenera of Chelonus were not recovered as monophyletic and thus do not represent valid subgenera. A total-evidence approach of 84 sequenced species and 16 dated fossil taxa to calibrate the molecular clock was performed to estimate the age of the subfamily and component genera. Divergence dating analyses and ancestral range reconstruction suggest that the Cheloninae evolved in the Neotropics 150 Ma ago. Prior to this study, 45 chelonine species were recognised from Australia, of which the majority were described more than 80 years ago. Yet there are many undescribed species, some of which could not be easily assigned to existing genera. Thus the first step of a taxonomic revision was to assess the current state of the fauna. This study evaluates the species richness of the Australian chelonines...

Molecular systematics and biogeographic history of oniscidean isopod troglofauna in groundwater calcretes of Central Western Australia.

Javidkar, Seyedmohammad
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado
Publicado em //2014
Relevância na Pesquisa
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Groundwater calcretes of central Western Australia have revealed an extraordinary diversity of short-range endemic invertebrate subterranean fauna. Although considerable attention has been given to the aquatic dwellers of the calcretes (stygofauna), the subterranean terrestrial fauna of the calcretes (troglofauna), particularly the oniscidean isopods, have been poorly studied. This thesis, including four data chapters, presents the results of multiple-gene and morphological analyses to establish a phylogenetic framework for elucidation of species diversity, systematics, and the biogeographic history of oniscidean isopod troglofauna in arid central Western Australia. The first data chapter focuses on higher level systematic relationships of the isopod fauna. In order to examine the monophyly of the family Platyarthridae, representatives of the main oniscidean families and genera from Australia, South America, Africa and Europe were analysed using molecular and morphological approaches, including data from a Scanning Electron Microscopy study. The phylogenetic analyses of mitochondrial and nuclear genes (COI, 18S, and 28S) showed that Platyarthridae is polyphyletic, and also revealed a very distinct Australian lineage with a unique water conducting system on antenna 2. Based on both morphological and molecular data...

Vergleichende Untersuchungen an der Hinterextremität palaeognather Vögel im Hinblick auf deren phylogenetische Systematik.; Comparative morphology on the hind limb of palaeognathous birds with respect to their phylogenetic systematics.

Brinkmann, Jan
Fonte: Universidade de Tubinga Publicador: Universidade de Tubinga
Tipo: Dissertação
DE_DE
Relevância na Pesquisa
36.71%
In dieser Arbeit werden Vertreter aus allen fünf lebenden palaeognathen Familien (Tinamidae, Rheidae, Struthionidae, Casuariidae incl. Dromaius, Apterygidae) an der Muskulatur ihrer Hinterextremität untersucht. Besonderes Augenmerk liegt dabei auf den Muskelbefestigungen und deren Knochenmarken sowie dem Verhältnis der Muskulatur zu anderen auffälligen Knochenstrukturen (z.B. Hypotarsus). Die Befunde werden nach den Prinzipien der Phylogenetischen Systematik ausgewertet. Als Außengruppen dienen dabei Neognathae und Crocodylia. Zur Homologie der Beinmuskeln von Vögeln und Crocodylia werden neue Hypothesen aufgestellt, die bei der femoro-tibialen Muskulatur eine Abweichung von der Nomina Anatomica Avium notwendig machen. Diese Untersuchung kann folgende Verwandtschaftsverhältnisse bestätigen, die auch andere morphologische Analysen postulieren, hingegen oft nicht das Ergebnis molekular-genetischer Arbeiten sind: Monophylie der Struthiones (d.h. große Laufvögel: Struthionidae, Rheidae und Casuariidae incl. Dromaius) und Schwestergruppen-Verhältnis zwischen Rheidae und Struthionidae. Abweichend von allen bisherigen Studien aber kommt diese Arbeit zu dem Schluss, dass die Apterygidae außerhalb eines Monophylum stehen, das Tinamidae und Struthiones umfasst und für welches hier der Name „Tinamitarsi“ vorgeschlagen wird. Gestützt wird diese Hypothese von einigen in dieser Arbeit erstmals beschriebenen Merkmale...

Sistemática de Syngonanthus; Systematics of Syngonanthus

Watanabe, Mauricio Takashi Coutinho
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 19/06/2015 PT
Relevância na Pesquisa
36.71%
Esta tese consta de três capítulos nos quais são abordados questões relacionadas à sistemática de Syngonanthus (Eriocaulaceae). No primeiro capítulo são apresentadas novidades taxonômicas, com descrições de novas espécies do gênero, incluindo a primeira espécie de flor exclusivamente trímera e bissexual da família. No segundo capítulo, uma análise filogenética com amostragem expandida de Syngonanthus é apresentada, para tentar elucidar questões relacionadas ao posicionamento do gênero em Paepalanthoideae; verificação e sustentação de classificações infragenéricas anteriores; e correlação de grupos bem sustentados com padrões morfológicos. O último capítulo é composto por uma revisão taxonômica de Syngonanthus sect. Carphocephalus, um dos grupos morfologicamente mais complexos no gênero. A revisão constou de um total de 13 espécies, nos quais foram propostos novos sinônimos, lectotipificações e descrição de novos táxons.; This thesis consists of three parts involving systematics of Syngonanthus (Eriocaulaceae). The chapter I consists on taxonomic novelties, with descriptions of new species, including the first species with exclusively trimerous and bisexual flowers in the family. The second chapter is the phylogenetic study of Syngonanthus with expanded sampling This study is an attempt to clarify issues related to the placement of Syngonanthus in Paepalanthoideae; to check the support and previous infrageneric classifications; and to correlate well supported groups with morphological patterns. The chapter three consists on a taxonomic revision of Syngonanthus sect. Carphocephalus...

Sulfosalt systematics: a review. Report of the sulfosalt sub-committee of the IMA Commission on Ore Mineralogy

Moelo, Y.; Makovicky, E.; Mozgova, N.; Jambor, J.; Cook, N.; Pring, A.; Paar, W.; Nickel, E.; Graeser, S.; Karup-Moller, S.; Balic-Zunic, T.; Mumme, W.; Vurro, F.; Topa, D.; Bindi, L.; Bente, K.; Shimizu, M.
Fonte: E. Schweizerbart’sche Verlagsbuchhandlung Publicador: E. Schweizerbart’sche Verlagsbuchhandlung
Tipo: Artigo de Revista Científica
Publicado em //2008 EN
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This report deals with a general reexamination of the systematics of sulfosalts. It represents an update of the activity of the Sulfosalt Sub-Committee within the Commission on Ore Mineralogy of the International Mineralogical Association, in connection with the Commission on New Minerals, Nomenclature and Classification (CNMNC-IMA). Part I presents generalities of sulfosalt definition and nomenclature. After an extended chemical definition of sulfosalts, attention is focused on "classic" sulfosalts with As3+, Sb3+, Bi3+ or Te4+ as cations, corresponding to the general formula (Me+, Me'2+, etc.)x [(Bi, Sb, As)3+,Te4+]y [(S, Se, Te)2–]z (Me, Me': various metals). General aspects of their chemistry and classification principles are summarized, especially with regard to chemical substitutions and modular analysis of complex crystal structures. On this basis, Part II presents a review of sulfosalt systematics. Six main crystal-chemical sub-groups are distinguished (plus some unclassified species), concerning more than 220 valid mineral species. Among others whose status is questioned are those considered to be varieties of well-defined species; minerals with ill-defined X-ray data; those that are possibly identical species; and those that represent the potential revalidation of old species. More than 50 crystal structures still remain unsolved...

Improving the Limit on the Electron EDM: Data Acquisition and Systematics Studies in the ACME Experiment

Hess, Paul William
Fonte: Harvard University Publicador: Harvard University
Tipo: Thesis or Dissertation
EN_US
Relevância na Pesquisa
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The ACME collaboration has completed a measurement setting a new upper limit on the size of the electron's permanent electric dipole moment (EDM). The existence of the EDM is well motivated by theories extending the standard model of particle physics, with predicted sizes very close to the current experimental limit. The new limit was set by measuring spin precession within the metastable H state of the polar molecule thorium monoxide (ThO). A particular focus here is on the automated data acquisition system developed to search for a precession phase odd under internal and external reversal of the electric field. Automated switching of many different experimental controls allowed a rapid diagnosis of major systematics, including the dominant systematic caused by non-reversing electric fields and laser polarization gradients. Polarimetry measurements made it possible to quantify and minimize the polarization gradients in our state preparation and probe lasers. Three separate measurements were used to determine the electric field that did not reverse when we tried to switch the field direction. The new bound of |de|< 8.7 × 10-29 e cm is over an order of magnitude smaller than previous limits, and strongly limits T-violating physics at TeV energy scales.; Physics

Exploiting the full potential of photometric quasar surveys: Optimal power spectra through blind mitigation of systematics

Leistedt, Boris; Peiris, Hiranya V.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
27.08%
We present optimal measurements of the angular power spectrum of the XDQSOz catalogue of photometric quasars from the Sloan Digital Sky Survey. These measurements rely on a quadratic maximum likelihood estimator that simultaneously measures the auto- and cross-power spectra of four redshift samples, and provides minimum-variance, unbiased estimates even at the largest angular scales. Since photometric quasars are known to be strongly affected by systematics such as spatially-varying depth and stellar contamination, we introduce a new framework of extended mode projection to robustly mitigate the impact of systematics on the power spectrum measurements. This technique involves constructing template maps of potential systematics, decorrelating them on the sky, and projecting out modes which are significantly correlated with the data. Our method is able to simultaneously process several thousands of nonlinearly-correlated systematics, and mode projection is performed in a blind fashion. Using our final power spectrum measurements, we find a good agreement with theoretical predictions, and no evidence for further contamination by systematics. Extended mode projection not only obviates the need for aggressive sky and quality cuts, but also provides control over the level of systematics in the measurements...

Reliable inference of exoplanet light curve parameters using deterministic and stochastic systematics models

Gibson, Neale P.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
27.18%
Time-series photometry and spectroscopy of transiting exoplanets allow us to study their atmospheres. Unfortunately, the required precision to extract atmospheric information surpasses the design specifications of most general purpose instrumentation, resulting in instrumental systematics in the light curves that are typically larger than the target precision. Systematics must therefore be modelled, leaving the inference of light curve parameters conditioned on the subjective choice of models and model selection criteria. This paper aims to test the reliability of the most commonly used systematics models and model selection criteria. As we are primarily interested in recovering light curve parameters rather than the favoured systematics model, marginalisation over systematics models is introduced as a more robust alternative than simple model selection. This can incorporate uncertainties in the choice of systematics model into the error budget as well as the model parameters. Its use is demonstrated using a series of simulated transit light curves. Stochastic models, specifically Gaussian processes, are also discussed in the context of marginalisation over systematics models, and are found to reliably recover the transit parameters for a wide range of systematics functions. None of the tested model selection criteria - including the BIC - routinely recovered the correct model. This means that commonly used methods that are based on simple model selection may underestimate the uncertainties when extracting transmission and eclipse spectra from real data...

Proposal of a new system of nomenclature for phylogenetic systematics

Papavero, Nelson; Llorente-Bousquets, Jorge; Abe, Jair Minoro
Fonte: Universidade de São Paulo. Museu de Zoologia. Publicador: Universidade de São Paulo. Museu de Zoologia.
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; Formato: application/pdf
Publicado em 02/03/2001 ENG
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After a brief study of the main concepts of the intuitive set theory, formal definitions of taxon, morphospecies and eidophoront are given. Follows a critical study of the creation of the Linnaean categories and why they cannot be maintained, and of the three different meanings of «genos» in evolutionary taxonomy (C-genos, P-genos and inf (P-genos)). Then, a new system of nomenclature is proposed for phylogenetic systematics, in which, without ever creating new names, all the species and all the proper subsets of a phylogenetic system are named. As the nomenclatural system becomes isomorphic with the phylogenetic system, the classification retrieves all the phylogenetic information, in the same order. The new system is based on the principle of absolute priority of names and, analogously, on Hennig's theory of phylogenetic systematics. Two taxa A and B are distinct if they possess nominal heterobathmy, i.e., if A possesses an autaponomastic and B possesses another; monophyly of A and B is indicated by the possession of a synaponomastic, which is formed by taking the name which has priority, adding a negative index: the synaponomastic of A and B will be automatically the autaponomastic of the immediate ancestral species of A and B. The process goes on until the species ancestral to the entire group is named. Many other conventions are established for the use of the system...

Systematics and evolutionary biology: uneasy bedfellows?

Schwartz,Jeffrey H.
Fonte: Instituto de Biología Publicador: Instituto de Biología
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2011 EN
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The history of systematics and evolutionary biology demonstrates how greatly the "modern evolutionary synthesis" instrumentally prevented, rather than facilitated, the intellectual growth and maturity of the diversity of evolutionary disciplines. In truth, the claim of the synthesis being synthetic is essentially without basis, indeed a myth. Instead, the "synthesis" had precisely the opposite effect: namely, squelching the arena of debate, disagreement, and diverse theorizing that had characterized the preceding decades. Although each of the 3 primary architects of the synthesis - Dobzhansky, Mayr, and Simpson - had his own agenda, they were united around the theme of population genetics and population thinking. When applied to systematics, especially by Mayr, the result can now be seen as confused at best. Perhaps this review will provoke a revival of earlier years of intellectual curiosity and fervor, and rekindle interest in systematic method and theory.