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Geometric morphometrics of the wing as a tool for assigning genetic lineages and geographic origin to Melipona beecheii (Hymenoptera: Meliponini)

FRANCOY, Tiago Mauricio; GRASSI, Marina Lopes; IMPERATRIZ-FONSECA, Vera Lucia; MAY-ITZA, William de Jesus; QUEZADA-EUAN, Jose Javier G.
Fonte: SPRINGER FRANCE Publicador: SPRINGER FRANCE
Tipo: Artigo de Revista Científica
Português
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The stingless bee Melipona beecheii presents great variability and is considered a complex of species. In order to better understand this species complex, we need to evaluate its diversity and develop methods that allow geographic traceability of the populations. Here we present a fast, efficient, and inexpensive means to accomplish this using geometric morphometrics of wings. We collected samples from Mexico, Guatemala, El Salvador, Nicaragua, and Costa Rica and we were able to correctly assign 87.1% of the colonies to their sampling sites and 92.4% to their haplotype. We propose that geometric morphometrics of the wing could be used as a first step analysis leaving the more expensive molecular analysis only to doubtful cases.; FAPESP[04/15801-0]; CNPq[151947/2007-4]; Sep-Conacyt[103341]

Misidentification of two Brazilian triatomes, Triatoma arthurneivai and Triatoma wygodzinskyi, revealed by geometric morphometrics

LAFUENTE, A. L. Carbajal de; ARAMILLO, N. J.; BARATA, J. M. S.; NOIREAU, F.; DIOTAIUTI, L.
Fonte: WILEY-BLACKWELL Publicador: WILEY-BLACKWELL
Tipo: Artigo de Revista Científica
Português
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Triatoma arthurneivai Lent & Martins and Triatoma wygodzinskyi Lent (Hemiptera: Reduviidae) are two Brazilian species found in the sylvatic environment. Several authors may have misidentified T. arthurneivai and consequently published erroneous information. This work reports the use of geometric morphometric analysis on wings in order to differentiate T. arthurneivai and T. wygodzinskyi, and thus to detect possible misidentifications. Triatomines collected from the field in the states of Minas Gerais and Sao Paulo, and from laboratory colonies, were used. Analyses show a clear differentiation between specimens of T. arthurneivai and T. wygodzinskyi. This indicates that T. arthurneivai populations from Sao Paulo state were misidentified and should be considered as T. wygodzinskyi. This study also suggests that T. arthurneivai is an endemic species from Serra do Cipo, Minas Gerais state.; Institut de Recherche pour le Developpement (IRD), France; Instituto Oswaldo Cruz (Fiocruz), Brazil; Fundacao Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES)/Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq), Brazil

Análise da variação longitudinal do esqueleto axial em Serpentes (Squamata) empregando ferramentas de morfometria geométrica; Analysis of the longitudinal variation in the axial skeleton of Serpentes (Squamata) using geometric morphometrics techniques

Machado, Fabio de Andrade
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 29/11/2010 Português
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As cobras são um grupo de vertebrados extremamente bem sucedido. Apesar da aparente simplicidade, elas conseguiram ocupar uma grande diversidade de habitats. O esqueleto axial das serpentes apresenta relação com vários aspectos da vida que puderam ter tido influência direta em seu sucesso evolutivo. Além disso, a forma dos elementos vertebrais possui valor taxonômico, fato que desperta particular interesse, visto que a maior parte do registro fóssil deste grupo é constituído por elementos vertebrais desarticulados. A morfometria geométrica utiliza informações sobre a posição de pontos em duas ou três dimensões, localizados sobre estruturas anatômicas para análise estatística da variação da forma. Esse conjunto de técnicas tem se mostrado eficaz em avaliar variações da forma que não seriam diagnosticadas por métodos tradicionais. O presente trabalho buscou avaliar as vértebras do esqueleto pré-cloacal de Serpentes no contexto da morfometria geométrica, considerando as influências ecológicas e filogenéticas sob estas estruturas, e investigando ainda a utilidade taxonômica da forma vertebral. Os resultados apresentados aqui sugerem a existência de uma padronização do esqueleto axial de serpentes que é conservada ao longo da história evolutiva desse grupo. Análises ecomorfológicas demonstram que a forma vertebral é fortemente influenciada por hábitos de vida como fossorialidade e constrição. A despeito da ausência de sinal filogenético...

Variação geográfica do boto-de-burmeister, Phocoena spinipinnis (Burmeister, 1865) (Cetacea : Phocoenidae) nas costas Atlântica e Pacífica da América do Sul

Schiller, Daniza Marcela Montserrat Molina
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Tese de Doutorado Formato: application/pdf
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Um total de 142 crânios do boto-de-Burmeister, Phocoena spinipinnis depositados em museus e coleções cientificas da Argentina, Brasil, Chile, Peru e Uruguai foram utilizados para explorar a variação geográfica em relação ao tamanho e forma do crânio de P. spinipinnis. Ademais, foi realizada uma caracterização oceanográfica da área de distribuição do boto-de- Burmeister através de dados históricos de temperatura, salinidade e oxigênio a 0 e 50m de profundidade na costa Atlântica e Pacifica. As idades dos animais foram obtidas pelas leituras das GLGs na dentina. A idade mais alta atingida por ambos os sexos foi de 10 anos. Medições na dentina mostraram dimorfismo sexual na primeira GLG e diferenças geográficas entre botos do Peru e Atlântico. Três tipos de anomalias foram registrados nos dentes, e a linha marcadora parece estar associada ao “El Niño”. Vinte e oito caracteres métricos foram utilizados para explorar o dimorfismo sexual e crescimento. A maturidade física do crânio foi estabelecida quando o comprimento côndilo-basal atingiu 95% do comprimento total (≥266mm nos machos e ≥277mm nas fêmeas). Diferenças no tamanho e forma do crânio foram analisadas através de morfometria tradicional e geométrica. Os resultados revelaram dimorfismo sexual...

Size and shape variability in the skull of Myotis nigricans (Schinz, 1821) (Chiroptera : Vespertilionidae) from two geographic areas in Brazil; Variação de tamanho e forma no crânio de Myotis nigricans (Schinz, 1821) (Chiroptera: Vespertilionidae) de duas áreas geográficas no Brasil

Bornholdt, Renata; Oliveira, Larissa Rosa de; Fabian, Marta Elena
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Artigo de Revista Científica Formato: application/pdf
Português
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Uma análise quantitativa do dimorfismo sexual e da variação geográfica do crânio de Myotis nigricans (Schinz, 1821) é apresentada através da morfometria geométrica. Diferenças no tamanho e na forma do crânio foram avaliadas através de imagens bidimensionais das vistas lateral e ventral do crânio, onde foram estabelecidos 30 marcos anatômicos. Os resultados indicaram a existência de dimorfismo sexual no tamanho do centróide do crânio para ambas as vistas estudadas. As fêmeas foram maiores que os machos. Contudo, não foi detectado dimorfismo sexual na forma do crânio de M. nigricans. A variação geográfica esteve presente no tamanho e na forma do crânio. Espécimes do Sul do Brasil tiveram tamanho do centróide maior que os espécimes do Ceará apenas na vista lateral. Diferenças na forma do crânio foram estatisticamente significativas em ambas as vistas: os espécimes do Sul do Brasil apresentaram-se brevirostri e com grande expansão na região posterior do crânio, enquanto os espécimes do Ceará apresentaram crânios longirostri e sem expansão posterior da caixa craniana. São discutidos fatores ecológicos para estes fenômenos.; We present a quantitative analysis of sexual dimorphism and geographic variation in the skull of Myotis nigricans (Schinz...

Variation in mandible shape in Thrichomys apereoides (Mammalia: Rodentia): Geometric analysis of a complex morphological structure

Duarte, Luiza Carla; Monteiro, Leandro Rabello; Von Zuben, Fernando José; Dos Reis, Sérgio Furtado
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 563-578
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The model of development and evolution of complex morphological structures conceived by Atchley and Hall in 1991 (Biol. Rev. 66:101-157), which establishes that changes at the macroscopic, morphogenetic level can be statistically detected as variation in skeletal units at distinct scales, was applied in combination with the formalism of geometric morphometrics to study variation in mandible shape among populations of the rodent species Thrichomys apereoides. The thin-plate spline technique produced geometric descriptors of shape derived from anatomical landmarks in the mandible, which we used with graphical and inferential approaches to partition the contribution of global and localized components to the observed differentiation in mandible shape. A major pattern of morphological differentiation in T. apereoides is attributable to localized components of shape at smaller geometric scales associated with specific morphogenetic units of the mandible. On the other hand, a clinal trend of variation is associated primarily with localized components of shape at larger geometric scales. Morphogenetic mechanisms assumed to be operating to produce the observed differentiation in the specific units of the mandible include mesenchymal condensation differentiation...

Size and shape variability in the skull of Myotis nigricans (Schinz, 1821) (Chiroptera: Vespertilionidae) from two geographic areas in Brazil

Bornholdt,R.; Oliveira,LR.; Fabián,ME.
Fonte: Instituto Internacional de Ecologia Publicador: Instituto Internacional de Ecologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2008 Português
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We present a quantitative analysis of sexual dimorphism and geographic variation in the skull of Myotis nigricans (Schinz, 1821) assessed by geometric morphometrics. Differences in size and shape of skulls were investigated using 30 landmarks plotted on two-dimensional images of lateral and ventral views. Results of geometric morphometrics revealed sexual dimorphism in the centroid size of the skull in both views. Females were larger than males. Nevertheless, there was no sexual dimorphism in skull shape of M. nigricans. Geographic variation was detected in size and shape of the skull. South Brazilian specimens were significantly larger than Ceará specimens only in the lateral view. Differences in skull shape were statistically significant in both views: specimens from South Brazil were brevirostri and presented a more expanded skull in the posterior region while Ceará specimens were longirostri and do not present any expansion in the brain case. Ecological factors for these phenomena are discussed in the text.

Morphometric variation of the Herichthys bartoni (Bean, 1892) species group (Teleostei: Cichlidae): How many species comprise H. labridens (Pellegrin, 1903)?

Mejía,Omar; Pérez-Miranda,Fabián; León-Romero,Yatzil; Soto-Galera,Eduardo; Luna,Efraín de
Fonte: Sociedade Brasileira de Ictiologia Publicador: Sociedade Brasileira de Ictiologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2015 Português
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Cichlids of the tribe Heroini have long been a source of taxonomical conflict. In particular, the species included in the Herichthys bartoni group have failed to be recovered as monophyletic in different molecular studies. In this paper we use traditional and geometric morphometrics to evaluate morphological variation in the species included in the H. bartoni complex in order to evaluate the number of species it contains. An update of a previously published DNA barcoding study suggests the existence of three genetic clusters that included the six recognized species analyzed in this study, none of them recovered as monophyletic. On the other hand, geometric morphometrics arise as a useful tool to discriminate species due that traditional morphometrics showed a high overlap in the characters analyzed that prevents the proposal of diagnostic characters.

Genetic architecture of mandible shape in mice: effects of quantitative trait loci analyzed by geometric morphometrics.

Klingenberg, C P; Leamy, L J; Routman, E J; Cheverud, J M
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /02/2001 Português
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This study introduces a new multivariate approach for analyzing the effects of quantitative trait loci (QTL) on shape and demonstrates this method for the mouse mandible. We quantified size and shape with the methods of geometric morphometrics, based on Procrustes superimposition of five morphological landmarks recorded on each mandible. Interval mapping for F(2) mice originating from an intercross of the LG/J and SM/J inbred strains revealed 12 QTL for size, 25 QTL for shape, and 5 QTL for left-right asymmetry. Multivariate ordination of QTL effects by principal component analysis identified two recurrent features of shape variation, which involved the positions of the coronoid and angular processes relative to each other and to the rest of the mandible. These patterns are reminiscent of the knockout phenotypes of a number of genes involved in mandible development, although only a few of these are possible candidates for QTL in our study. The variation of shape effects among the QTL showed no evidence of clustering into distinct groups, as would be expected from theories of morphological integration. Further, for most QTL, additive and dominance effects on shape were markedly different, implying overdominance for specific features of shape. We conclude that geometric morphometrics offers a promising new approach to address problems at the interface of evolutionary and developmental genetics.

The Utility of Geometric Morphometrics to Elucidate Pathways of Cichlid Fish Evolution

Kerschbaumer, Michaela; Sturmbauer, Christian
Fonte: SAGE-Hindawi Access to Research Publicador: SAGE-Hindawi Access to Research
Tipo: Artigo de Revista Científica
Publicado em 26/05/2011 Português
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Fishes of the family Cichlidae are famous for their spectacular species flocks and therefore constitute a model system for the study of the pathways of adaptive radiation. Their radiation is connected to trophic specialization, manifested in dentition, head morphology, and body shape. Geometric morphometric methods have been established as efficient tools to quantify such differences in overall body shape or in particular morphological structures and meanwhile found wide application in evolutionary biology. As a common feature, these approaches define and analyze coordinates of anatomical landmarks, rather than traditional counts or measurements. Geometric morphometric methods have several merits compared to traditional morphometrics, particularly for the distinction and analysis of closely related entities. Cichlid evolutionary research benefits from the efficiency of data acquisition, the manifold opportunities of analyses, and the potential to visualize shape changes of those landmark-based methods. This paper briefly introduces to the concepts and methods of geometric morphometrics and presents a selection of publications where those techniques have been successfully applied to various aspects of cichlid fish diversification.

Leaf Morphology, Taxonomy and Geometric Morphometrics: A Simplified Protocol for Beginners

Viscosi, Vincenzo; Cardini, Andrea
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 03/10/2011 Português
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Taxonomy relies greatly on morphology to discriminate groups. Computerized geometric morphometric methods for quantitative shape analysis measure, test and visualize differences in form in a highly effective, reproducible, accurate and statistically powerful way. Plant leaves are commonly used in taxonomic analyses and are particularly suitable to landmark based geometric morphometrics. However, botanists do not yet seem to have taken advantage of this set of methods in their studies as much as zoologists have done. Using free software and an example dataset from two geographical populations of sessile oak leaves, we describe in detailed but simple terms how to: a) compute size and shape variables using Procrustes methods; b) test measurement error and the main levels of variation (population and trees) using a hierachical design; c) estimate the accuracy of group discrimination; d) repeat this estimate after controlling for the effect of size differences on shape (i.e., allometry). Measurement error was completely negligible; individual variation in leaf morphology was large and differences between trees were generally bigger than within trees; differences between the two geographic populations were small in both size and shape; despite a weak allometric trend...

Lujiatun Psittacosaurids: Understanding Individual and Taphonomic Variation Using 3D Geometric Morphometrics

Hedrick, Brandon P.; Dodson, Peter
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 09/08/2013 Português
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Psittacosaurus is one of the most abundant and speciose genera in the Dinosauria, with fifteen named species. The genus is geographically and temporally widespread with large sample sizes of several of the nominal species allowing detailed analysis of intra- and interspecific variation. We present a reanalysis of three separate, coeval species within the Psittacosauridae; P. lujiatunensis, P. major, and Hongshanosaurus houi from the Lujiatun beds of the Yixian Formation, northeastern China, using three-dimensional geometric morphometrics on a sample set of thirty skulls in combination with a reevaluation of the proposed character states for each species. Using these complementary methods, we show that individual and taphonomic variation are the joint causes of a large range of variation among the skulls when they are plotted in a morphospace. Our results demonstrate that there is only one species of Psittacosaurus within the Lujiatun beds and that the three nominal species represent different taphomorphotypes of P. lujiatunensis. The wide range of geometric morphometric variation in a single species of Psittacosaurus implies that the range of variation found in other dinosaurian groups may also be related to taphonomic distortion rather than interspecific variation. As the morphospace is driven primarily by variation resulting from taphonomic distortion...

Geometric Morphometrics of Rodent Sperm Head Shape

Varea Sánchez, María; Bastir, Markus; Roldan, Eduardo R. S.
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 28/11/2013 Português
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Mammalian spermatozoa, particularly those of rodent species, are extremely complex cells and differ greatly in form and dimensions. Thus, characterization of sperm size and, particularly, sperm shape represents a major challenge. No consensus exists on a method to objectively assess size and shape of spermatozoa. In this study we apply the principles of geometric morphometrics to analyze rodent sperm head morphology and compare them with two traditional morphometry methods, that is, measurements of linear dimensions and dimensions-derived parameters calculated using formulae employed in sperm morphometry assessments. Our results show that geometric morphometrics clearly identifies shape differences among rodent spermatozoa. It is also capable of discriminating between size and shape and to analyze these two variables separately. Thus, it provides an accurate method to assess sperm head shape. Furthermore, it can identify which sperm morphology traits differ between species, such as the protrusion or retraction of the base of the head, the orientation and relative position of the site of flagellum insertion, the degree of curvature of the hook, and other distinct anatomical features and appendices. We envisage that the use of geometric morphometrics may have a major impact on future studies focused on the characterization of sperm head formation...

Caracterização populacional de Mourella caerulea (Friese, 1900) e Plebeia nigriceps (Friese, 1901) (Hymenoptera, Apidae, Meliponini) através de morfometria geométrica da asa, análise de hidrocarbonetos cuticulares e DNA mitocondrial; Characterization of population of Mourella caerulea (Friese, 1900) and Plebeia nigriceps (Friese, 1901) (Hymenoptera: Apidae: Meliponini) through geometric morphometrics of wings, analysis of cuticular hydrocarbons and mtDNA.

Teixeira, Juliana Stephanie Galaschi
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 07/05/2015 Português
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Mourella caerulea, popularmente conhecida como mirim-de-chão ou bieira, e Plebeia nigriceps, comumente chamada mirim nigriceps, são meliponíneos ocorrentes no sul do Brasil, polinizadores de plantas nativas e cultivadas. M. caerulea está principalmente relacionada ao bioma Pampa e seu hábito de nidificação é subterrâneo. P. nigriceps nidifica em frestas de rochas e muros, sendo encontrada tanto no Pampa como em Mata Atlântica. O presente trabalho teve como objetivo avaliar a variabilidade populacional destas duas espécies, através de três metodologias: a morfometria geométrica de asa, perfil de hidrocarbonetos cuticulares e sequenciamento de fragmentos de genes mitocondriais. Foram coletadas operárias de 24 colônias de M. caerulea em cinco localidades de sua distribuição natural e 53 colônias de P. nigriceps em oito localidades no estado do Rio Grande do Sul. Para análise do padrão de venação da asa, foram marcados 13 marcos anatômicos na asa anterior direita de cinco a 20 operárias por colônia. A análise genética foi realizada avaliando um fragmento do gene Citocromo Oxidase I em M. caerulea, e Citocromo B em P. nigriceps. A análise morfométrica demonstrou estruturação dos grupos com separação estatisticamente significativa (<0...

Geometric Morphometrics for Mathematica (Ver. 9.0)

Polly, P. David
Fonte: P. David Polly Publicador: P. David Polly
Tipo: Software
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This Mathematica add-on package performs common geometric morphometric functions. Includes Procrustes superimposition, thin-plate spline graphics, Centroid Size calculation, Procrustes distance calculation, Mantel tests, Ancestral Node reconstruction, Eclidean Distance Matrix Analysis (EDMA), and import function for TPS files. Installation: The file is a ".m" file, which can be imported into Mathematica 6.0 and later (functions do not work in earlier versions of Mathematica). Install using the "Install" item on the "File" menu. Once installed, you must load the package like any other with the line "<

Tooth and cranial disparity in the fossil relatives of Sphenodon (Rhynchocephalia) dispute the persistent 'living fossil' label

Meloro, C.; Jones, M.E.H.
Fonte: Wiley Publicador: Wiley
Tipo: Artigo de Revista Científica
Publicado em //2012 Português
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The tuatara (Sphenodon punctatus) is the only living representative of Rhynchocephalia, a group of small vertebrates that originated about 250 million years ago. The tuatara has been referred to as a living fossil; however, the group to which it belongs included a much greater diversity of forms in the Mesozoic. We explore the morphological diversity of Rhynchocephalia and stem lepidosaur relatives (Sphenodon plus 13 fossil relatives) by employing a combination of geometric morphometrics and comparative methods. Geometric morphometrics is used to explore cranium size and shape at interspecific scale, while comparative methods are employed to test association between skull shape and size and tooth number after taking phylogeny into account. Two phylogenetic topologies have been considered to generate a phylomorphospace and quantify the phylogenetic signal in skull shape data, the ancestral state reconstruction as well as morphological disparity using disparity through time plots (DTT). Rhynchocephalia exhibit a significant phylogenetic signal in skull shape that compares well with that computed for other extinct vertebrate groups. A consistent form of allometry has little impact on skull shape evolution while the number of teeth significantly correlates with skull shape also after taking phylogeny into account. The ancestral state reconstruction demonstrates a dramatic shape difference between the skull of Sphenodon and its much larger Cretaceous relative Priosphenodon. Additionally...

Morphometrical diagnosis of the malaria vectors Anopheles cruzii, An. homunculus and An. bellator

Lorenz, Camila; Marques, Tatiani Cristina; Sallum, Maria Anice Mureb; Suesdek, Lincoln
Fonte: BIOMED CENTRAL LTD; LONDON Publicador: BIOMED CENTRAL LTD; LONDON
Tipo: Artigo de Revista Científica
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Background: Anopheles (Kerteszia) cruzii is a primary vector of Plasmodium parasites in Brazil's Atlantic Forest. Adult females of An. cruzii and An. homunculus, which is a secondary malaria vector, are morphologically similar and difficult to distinguish when using external morphological characteristics only. These two species may occur syntopically with An. bellator, which is also a potential vector of Plasmodium species and is morphologically similar to An. cruzii and An. homunculus. Identification of these species based on female specimens is often jeopardised by polymorphisms, overlapping morphological characteristics and damage caused to specimens during collection. Wing geometric morphometrics has been used to distinguish several insect species; however, this economical and powerful tool has not been applied to Kerteszia species. Our objective was to assess wing geometry to distinguish An. cruzii, An. homunculus and An. bellator. Methods: Specimens were collected in an area in the Serra do Mar hotspot biodiversity corridor of the Atlantic Forest biome (Cananeia municipality, State of Sao Paulo, Brazil). The right wings of females of An. cruzii (n= 40), An. homunculus (n= 50) and An. bellator (n= 27) were photographed. For each individual...

Allometry and ontogeny in Callibia diana Stål (Mantodea: Acanthopidae)

Avendaño,J; Sarmiento,CE
Fonte: Sociedade Entomológica do Brasil Publicador: Sociedade Entomológica do Brasil
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2011 Português
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The life-cycle of Callibia diana Stål is described and linear and geometric morphometrics are used for studying allometrics and shape changes throughout this neotropical mantid species' life-cycle. Significant changes were expected in the allometry and shape of the raptorial leg and abdomen, given the importance of hunting and reproduction. The allometric slopes were obtained by using total length as the independent variable. Geometric morphometrics of landmarks were used for frontal femur and tibia. Hunting and reproduction-related structures had the steepest slopes and positive allometries. Negative growth of both disc width and head width found in the last moulting event may be a consequence of prothoracic muscle growth which is responsible for predatory strike strength. The tibial claw and femur of the raptorial leg become larger, while their spines become more orthogonal to the longitudinal axes which may facilitate prey retention. These changes in mantid shape throughout ontogeny were consistent and suggested the resource allocation and development programming of the body that improved reaching distance and prey retention.

Revision of the systematic status of patagonian and pampean gray foxes (Canidae: Lycalopex griseus and Lycalopex gymnocercus) using 3 D Geometric Morphometrics

Prevosti, Francisco Juan; Segura, Valentina; Cassini, Guillermo Hernán; Martin, Gabriel Mario
Fonte: Sociedad Argentina para el Estudio de los Mamíferos Publicador: Sociedad Argentina para el Estudio de los Mamíferos
Tipo: info:eu-repo/semantics/article; info:ar-repo/semantics/artículo; info:eu-repo/semantics/publishedVersion Formato: application/pdf
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Argentinean "zorros de campo" are currently included in two species: Lycalopex griseus and L. gymnocercus. Lycalopex gymnocercus lives in northern Patagonia and in most of central and northern Argentina. Lycalopex griseus is smaller and lives in Patagonia and throughout western Argentina. A previous traditional morphometric study using cranio-dental measurements considered both forms to be the same species, showing clinal reduction in size from northeastern to northwestern Argentina. Here we tested the synonymy of these foxes and the existence of clinal variation using a large sample and geometric morphometric methods. Our results rejected the separation of these foxes in two different species and confirmed, based on cranium and mandible size and shape that they belong to the same species. Also, we show there is a clinal variation in size that has an allometric component in cranial and mandibular shape, which accounts for the differences between these foxes.; Revisión del estatus sistemático de los zorros grises patagónico y pampeano (Canidae: Lycalopex griseus y L. gymnocercus) usando morfometría geométrica 3D. Los zorros argentinos de campo son incluidos en dos especies: Lycalopex griseus y L. gymnocercus. Lycalopex gymnocercus habita el norte de Patagonia y gran parte del centro y norte del país...

Morfometría geométrica de la superficie oclusal de dientes de lirones (Gliridae, Rodentia, Mammalia): estudio preliminar, problemas y posibles aplicaciones; A preliminar geometric morphometric analysis of the oclusal surface of dormouse teeth (Gliridae, Rodentia, Mammalia): problems and possible applications.

García Paredes, Israel
Fonte: Universidad Complutense de Madrid Publicador: Universidad Complutense de Madrid
Tipo: Artículo Formato: 1260812 bytes; application/pdf
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[ES] Se presenta un trabajo preliminar para comprobar la aplicabilidad de la morfometría geométrica basada en la definición de landmarks para el estudio de la superficie oclusal de los dientes yugales de lirones o glíridos (Gliridae, Rodentia, Mammalia). Como ejemplo se analiza una muestra de M1 y M2 pertenecientes a la especie Armantomys jasperi DAAMS, 1990 en cuya superficie oclusal son definidos 22 landmarks. El diseño experimental realizado permite la identificación de landmarks y la comparación de los distintos especímenes mediante métodos de superposición. Un análisis de conglomerados jerárquicos muestra la adecuación del método planteado para agrupar M1 y M2. Se ha realizado además un análisis discriminante para ver el porcentaje de acierto en la predicción de cada grupo de molares superiores. Gracias a la exploración efectuada se ha identificado un ejemplar mal clasificado y, preliminarmente, la separación entre M1 y M2 es satisfactoria.; [EN] A preliminary work to test the landmark-based geometric morphometrics methods for the study of dental crown pattern of upper cheek teeth of glirids or dormouse (Gliridae, Rodentia, Mammalia) is presented. As an example, a sample of the fossil especies Armantomys jasperi DAAMS...