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1.
Malaysian Journal of Medicine and Health Sciences ; : 134-142, 2024.
Article in English | WPRIM | ID: wpr-1012678

ABSTRACT

@#Introduction: Race estimation of unknown individual is essential in forensic investigation. The resiliency of frontal sinus makes it a potential tool for biological profiling, particularly in cases where fragmented skeleton persists. Geometric morphometrics is an efficient way to characterise shape. However, the use of frontal sinus to identify race of Malaysians is yet to be investigated. This research employed a two-dimensional (2D) geometric morphometric to examine the morphological differences of the frontal sinus among the major races in Malaysia. Methods: Lateral skull radiographs which comprising of 453 adult Malaysian (151 Malays, Chinese and Indian respectively) were used. The 2D landmarks of eight were placed on the digitalized radiographs and 2D geometric morphometric analysis was performed using MorphoJ software. Results: Procrustes ANOVA revealed a significantly different frontal sinus shape (p-value < 0.05) between races. Canonical variate analysis showed significantly different frontal sinus morphology (p-value < 0.05) between Malay and Indian as well as Chinese and Indian. Discriminant function analysis with cross-validation demonstrated a 57.4% accuracy rate. Conclusion: This population-specific study based on frontal sinus of Malaysians using the 2D geometric morphometric, though less reliable, sheds new light on the potential applicability of this method for race estimation purpose.

2.
Rev. biol. trop ; 68(1)mar. 2020.
Article in English | LILACS-Express | LILACS | ID: biblio-1507646

ABSTRACT

Introduction: The gastropod Bostryx torallyi shows high variability in shell shape and coloration. Subspecies of this organism have been described based on shell characters but, since they were slightly different, they were synonymized afterwards. Until now, shell variability has been analyzed only descriptively and its anatomy is still unknown. Objective: In this study, I provide anatomical information of B. torallyi and apply a geometric morphometric analysis to evaluate the shell shape variation among specimens. Methods: To accomplish this, type material and numerous lots were examined and dissected out. Additionally, relative warp analysis, based on 9 landmarks in ventral view of the shell, was performed using 80 specimens of 9 localities from Bolivia and Argentina. Results: According to our results, geometric morphometrics is a suitable method to evaluate differences in shell shape among localities; for instance, distinctions in the shell were noticeable between gastropods of low and high altitudes. On the other hand, it was established that the coloration of this species is independent of large-scale factors since the examined specimens came from environments with similar conditions. Furthermore, the sculpture of the protoconch and anatomy of B. torallyi coincided with the other Argentinian species of the genus. Conclusions: Therefore, I concluded that a geometric morphometric analysis of shell shape is a good complement to traditional qualitative description of the characteristics of the shell in this species.


Introducción: El gasterópodo Bostryx torallyi exhibe una gran variabilidad en la forma y coloración de su concha. Subespecies de este organismo han sido descritas con base en los caracteres de la concha; pero, dadas las sutiles diferencias, fueron luego sinonimizadas. Hasta el momento, la variabilidad de la concha ha sido analizada solo descriptivamente y su anatomía es aún desconocida. Objetivo: En este estudio, los objetivos fueron:proveer información anatómica de B. torallyi y usar un análisis de morfometría geométrica para evaluar la variación de la forma de la concha entre especímenes. Métodos: Para ello, se examinó y disectó material tipo y numerosos lotes. Adicionalmente, se realizaron análisis del "relative warp", basados en nueve "landmarks" en vista ventral de la concha, empleando 80 especímenes de nueve localidades de Bolivia y Argentina. Resultados: De acuerdo con los resultados, la morfometría geométrica resultó útil para demostrar diferencias en forma de la concha entre localidades; por ejemplo, se detectarondiferencias evidentes entre localidades de alta y baja altitud. Se determinó que la variación en la coloración de esta especie es independiente de factores a gran escala, dado que los especímenes examinados proceden de ambientes con condiciones similares. Por otro lado, la escultura de la protoconcha y la anatomía de B. torallyi resultaron coincidentes con la de otras especies de este género recolectadas en Argentina. Conclusiones: Se concluyó que el análisis de morfometría geométrica de la forma de la concha fue un buen complemento a la descripción cualitativa tradicional de caracteres de concha.

3.
Acta Anatomica Sinica ; (6): 306-312, 2020.
Article in Chinese | WPRIM | ID: wpr-1015581

ABSTRACT

Based on the data collection and analysis of the sample landmarks, the geometric morphological method shows great prospect in the study of human remains. The purpose of this paper is to briefly outline the application of geometric morphological method in research of human remains and gives an outlook on the application of the method in the study of ancient children.

4.
Rev. biol. trop ; 67(6)dic. 2019.
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1507583

ABSTRACT

Introducción: La variación morfológica intraespecífica puede ser el resultado del desarrollo ontogénico, la variación genética o la heterogeneidad ambiental. En el último caso, los organismos están expuestos a diversas condiciones ambientales, lo que puede influir en el comportamiento y las adaptaciones morfológicas de las especies. Precisamente, el Corredor Arrecifal del Suroeste del Golfo de México (CASGM) está compuesto por arrecifes separados geográficamente que están expuestos a diferentes factores oceanográficos, así como atributos propios con múltiples variables ambientales. Por lo tanto, es posible encontrar diferencias morfológicas de las poblaciones de especies que se distribuyen en el corredor. Objetivo: Determinar la variación morfológica de la linterna de Aristóteles del erizo de mar Eucidaris tribuloides a lo largo del CASGM. Métodos: Se analizó la relación alométrica entre la altura de la linterna versus diámetro de la testa en 104 especímenes, también realizamos un análisis de covarianza para detectar diferencias alométricas entre grupos. Se analizó la variación de la forma de una rótula y una semipirámide de cada erizo de mar mediante morfometría geométrica. Resultados: Existen diferencias alométricas entre sistemas arrecifales. La forma de la rótula y semipirámide de los erizos de mar del norte son diferentes a los erizos del centro y el sur; sin embargo, no hubo diferencias de forma entre el centro y el sur. El tamaño centroide de la rótula y semipirámide de los erizos de mar del norte son significativamente más grandes que los del centro y el sur. Conclusiones: A lo largo del Corredor Arrecifal del Suroeste del Golfo de México, los individuos de E. tribuloides mostraron variación morfológica en sus estructuras analizadas, dichos resultados, pueden ser explicados por los gradientes latitudinales y ambientales del CASGM, además de los hábitos alimenticios de la especie y la disponibilidad del recurso alimenticio en el ambiente donde se establecen.


Introduction: Intraspecific morphological variation can be attributed to the result of genetic variation or influence of environmental heterogeneity. In the latter case, organisms are exposed to diverse environmental conditions which have an influence on their biological processes and can be seen reflected in the morphological adaptations of species. Indeed, Reef Corridor in the Southwest Gulf of Mexico (CASGM, in its Spanish acronym) is constituted of geographically separated reefs that are exposed to different large-scale oceanographic factors and show their own attributes with multiple environmental variables. Therefore, this can stimulate morphological variations of species populations that are distributed in this corridor. Objective: The aim of this study was to determine the morphological variation of the Aristotle's lantern of the sea urchin Eucidaris tribuloides along CASGM. Methods: The allometric relation between height of the Aristotle's lantern and diameter of the test of 104 specimens was analyzed, and we also used a covariance analysis to detect allometric differences between groups. Apart from that, the variation of the shape of a rotule and a demi-pyramid for each sea urchin were analyzed using geometric morphometry. Results: There are allometric differences among reef systems in the north, center and south of Veracruz. The shape of rotula and demi-pyramid of sea urchins of the north zone are different from the central and south area. However, there were no differences in shape between the center and the South area. The centroid size of rotula and demi-pyramid of the sea urchins of the North are larger than those in the center and the South. Conclusions: Along the Corridor of the Southwest of the Gulf of Mexico, specimens of E. tribuloides showed a morphological variation in their analyzed structures, these results can be explained by the geographical and environmental gradients of the CASGM, in addition to the feeding habits of E. tribuloides and the availability of the food resource in the habitat where they are established. As a stimulus to the morphological variation found in this research, the distance among the reef systems and the marine currents patterns are also considered.

5.
Braz. J. Vet. Res. Anim. Sci. (Online) ; 56(1): e150704, jun. 2019. ilus, tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1007816

ABSTRACT

Organisms can develop different kinds of asymmetry when deviations from expected perfect symmetry occur. Among others are fluctuating asymmetry (FA) and directional asymmetry (DA). FA represents small random differences between corresponding parts on the left and right sides of an individual in bilaterally paired structures. It is thought that FA reflects an organism's ability to cope with genetic and environmental stress during growth. DA occurs whenever one side on the plane of symmetry develops more than the other side, and has a genetic component. In this research, we examined the expression of morphological symmetry in 38 skulls of different age groups of wild boar (Sus scrofa), on their ventral aspect, using two-dimensional coordinates of 27 landmarks. Analyses showed the presence of significant FA and DA in the entire sample, detecting also distinctive differences between age groups. The obtained results show that the shape differences in different age groups could reasonably be a consequence of a response to environmental factors for FA and a masticatory lateralization for DA.(AU)


Os organismos podem desenvolver diferentes tipos de assimetria quando ocorrem desvios da pefeita simetria esperada. Entre os diversos tipos de assimetria existentes duas merecem especial destaque: a flutuante (AF) e a directional (AD). A AF é representada por pequenas diferenças casuais entre as partes correspondents das laterais direita e esquerda de um indivíduo em estruturas pareadas bilateralmente; acredita-se que elas reflitam a habilidade de um organismo adaptar-se a fatores estressantes genéticos e ambientais observados durante o seu crescimentos. A AD ocorre quando um lado da assimetria plana desenvolve-se mais do que o outro e há um componente genético. No presente trabalho foi analisada a expresssão da simetria morfológica de 38 crânios de diferentes grupos etários de javalis (Sus scrofa), nos seus aspectos ventrais, com o emprego de duas coordenadas dimensionais de 27 pontos anatômicos homólogos. As análises efetuadas revelaram a existência de valores significantes de AF e AD em toda a amostra trabalhada, detectando inclusive diferenças entre os grupos etários. Os resultados obtidos demonstraram que as diferentes formas observadas nos diferentes grupos etários podem ser consequência de uma resposta a fatores ambientais para a AF e a lateralização da mastigação para a AD.(AU)


Subject(s)
Animals , Sus scrofa/anatomy & histology , Sus scrofa/abnormalities , Facial Asymmetry/diagnosis , Mastication
6.
Article | IMSEAR | ID: sea-187958

ABSTRACT

Culture potentialities of the hybrids from crosses between Oreochromis niloticus (Linnaeus, 1758) and Sarotherodon melanotheron (Rüppel, 1852) were assessed in breeding design through morphological features using geometric morphometric approach. The crosses and rearing procedure, that lasted six months, are performed into a concrete pond at Layo Aquaculture Station. The morphological studies were undertaken with morphometric biomarkers such as average body shape and components of developmental homeostasis (canalisation and developmental stability). Average body shape between groups was investigated using Relative Warps Analysis (RWA) and Canonical Variates Analysis (CVA), whereas canalisation and fluctuating asymmetry were evaluated from ANOVA Procrustes. The results showed that the body shape of the hybrids is intermediate between those of the two parental species and that the reciprocal hybrids of first generation exhibit heterosis in size. This hybrid vigor appeared more on the hybrids resulting from crosses between S. melanotheron males and O. niloticus females. In a general way, the morphology of the head of the hybrids is similar to that of the parent O. niloticus and their fins resembled to those of the parent S. melanotheron. Moreover, fluctuating asymmetry in shape does not vary between parental species and hybrids, contrary to fluctuating asymmetry in size, which is lesser in latter. Canalisation was found to be smaller in the hybrids compared to the parental ones. So, these results revealed that the hybrids could benefit from most of accrued advantages of parental species.

7.
Rev. biol. trop ; 64(1): 289-303, ene.-mar. 2016. tab, ilus
Article in Spanish | LILACS | ID: biblio-843278

ABSTRACT

ResumenLos escarabajos pasálidos son componentes importantes de los bosques tropicales debido a que facilitan el reciclaje de nutrientes propios de madera en descomposición, ya sea por acción directa (consumo) o indirecta (facilitando la acción de otros organismos). En la actualidad los estudios ecológicos dentro del grupo son escasos y se han centrado en respuestas a cambios ambientales relacionados con su recurso alimenticio. En el presente estudio se caracterizó la composición gremial de escarabajos pasálidos, distribuida en un gradiente altitudinal, de acuerdo a sus características de aprovechamiento del recurso. Se cuantificaron aspectos morfoecológicos de importancia adaptativa para la explotación diferencial del recurso (medidas corporales, puntos homólogos en cuerpo y alas y series de Fourier en protibias). Se reconocieron cinco especies, 198 grupos familiares y tres gremios: el subcortícola, el alboduramícola y el generalista. La riqueza de la comunidad disminuyó conforme aumentó la altitud. Los cambios entre las variables morfométricas lineales se vieron influenciadas por la altitud; por su parte, los datos morfogeométricos se comportaron independientes del gradiente. El análisis de marcadores morfológicos (morfogeométrico) arrojó información relevante para la delimitación de los gremios ya establecidos en esta familia. Dentro de estos, la forma general del cuerpo junto a las tibias anteriores, aportaron la mayor información de agrupación gremial. La cuantificación de dichos marcadores evidenció la relación entre los tipos de aprovechamiento del recurso, ya que al ser estructuras importantes en el movimiento y consumo de la madera en microzonas particulares, permite plantear roles funcionales puntuales. Reconocer estas variables en interacción con aquellas ecológicas brinda herramientas para el entendimiento de la riqueza y los aportes funcionales de los escarabajos pasálidos al ecosistema.


AbstractBess beetles are important components on tropical forest dead wood nutrient cycling, since they act as direct consumers and ease the consumption by another organism (indirect). Studies of bess beetle ecology are scarce and have focused on communities responses to environmental changes on alimentary resources. We characterized the bess beetles guild composition in an elevation gradient, according to their differential use of resources (microhabitat) and morphological traits quantification (geometric and lineal), as a potential tool to improve our understanding on resource use and functional ecology of beetles. Three guilds (underbark, sapwood-heartwood and generalists feeders), five species and 198 familiar groups were recognized; their richness decreased as elevation increased. Changes in linear morphometric measures were influenced by elevation; morphogeometrical measures were not associated with the elevation gradient, only grouping at guild level were observed. Morphological markers analysis (morphometric) provided information to guild delimitation. Body and metatibiae shape contributed with the best information to guild grouping. Quantification of those structural markers proved the relationship between resource repartition, because they are involved in movement on wood galleries and wood consumption, this fact allowed to propose specific functional roles. The identified patterns have contributed on the understanding of functional processes in Passalidae communities and their role in ecosystem function.


Subject(s)
Animals , Coleoptera/anatomy & histology , Tropical Climate , Coleoptera/classification , Coleoptera/physiology , Forests , Colombia , Biodiversity
8.
Int. j. morphol ; 31(3): 905-910, set. 2013. ilus
Article in Spanish | LILACS | ID: lil-694976

ABSTRACT

Se ha descrito que el medio aéreo representa menos problemas a los organismos en relación con la hipoxia a excepción de circunstancias especiales, como la exposición a grandes alturas o las madrigueras. El ambiente de gran altitud es desafiante en diversos sentidos, dado que existen factores bióticos y abióticos que pueden interactuar para determinar la distribución y sobrevivencia de los organismos. Para conocer estos aspectos, la biología se apoya en la ecomorfología, área que ayuda a definir las diferencias morfológicas con respecto al cambio del hábitat y en la morfometría geométrica que permite analizar estadísticamente esos cambios. En el presente estudio, se evaluaron diferentes poblaciones de la rana Hyla plicata que es una de las especies que se distribuyen a mayor altitud en México, (1500 m hasta los 3700 m). Por lo que el objetivo de este estudio, fue analizar la morfología del corazón en Hyla plicata a través de un gradiente altitudinal. Para ello se colectaron organismos en cuatro localidades, una de ellas fue en La Cima (Distrito Federal a 3016 m), y tres ubicadas en el Estado de México: Buenavista (3200 m), El Cerrillo ( 2632 m) y San Juan Atezcapan (1860 m). Los organismos colectados se disectaron para extraer el corazón con la finalidad de digitalizarlos mediante fotografías, y analizarlos con puntos geométricos y de esta forma evaluar la forma del órgano. Los resultados indican que las localidades de mayor altitud presentan aurículas y ventrículos más ensanchados, lo que señala que esta estructura evolucionó y se adaptó para efectuar un bombeo más eficaz de la sangre y posteriormente dirigirla hacia los diferentes tejidos del cuerpo. Esta adaptación en la morfología del corazón, permitió que Hyla plicata se adaptara a los ambientes de alta montaña como se ha visto en otros vertebrados que habitan zonas de mayor altitud.


It has been reported that the air environment is less problematic for organisms in relation to hypoxia except for special circumstances, such as exposure to high altitudes or burrows. The high altitude environment is challenging in different ways, since there are biotic and abiotic factors may interact to determine the distribution and survival of organisms. For these aspects, biology is based on the ecomorphology, area that helps to define the morphological differences with respect to habitat change and geometric morphometrics to analyze statistically those changes. In the present study, we evaluated different populations of the frog Hyla plicata is a species that are distributed at higher elevations in Mexico (1500 m to 3700 m). For the purpose of this study was to analyze the morphology in Hyla plicata heart through an altitudinal gradient. The organisms were collected at four sites, one was located in La Cima (Distrito Federal to 3016 m), and three in the Estado of Mexico: Buenavista (3200 m), El Cerrillo (2632 m) and San Juan Atezcapan (1860 m). The organisms collected were dissected to extract the heart for the purpose of scan them through photographs, and analyzed with geometric points and thus evaluate the shape of the organ. The results indicate that higher altitude locations have enlarged atria and ventricles, indicating that this structure evolved and adapted to effect a more efficient pumping of blood and then direct it to different body tissues. This adaptation in the morphology of the heart, allowed to adapt to Hyla plicata in high altitude environments as seen in other vertebrates that inhabit higher elevations.


Subject(s)
Humans , Animals , Anura/anatomy & histology , Heart/anatomy & histology , Adaptation, Physiological , Altitude , Mexico
9.
Neotrop. entomol ; 37(5): 558-563, Sept.-Oct. 2008. ilus, tab
Article in English | LILACS | ID: lil-498326

ABSTRACT

Drosophila serido Vilela & Sene é uma espécie cactofílica e politípica, com ampla distribuição geográfica no Brasil. A morfologia do edeago de indivíduos provenientes de oito populações naturais de D. serido foi avaliada. De acordo com as características dos seus edeagos, as populações de D. serido foram discriminadas com eficiência de aproximadamente 75 por cento. O resultado do teste de Mantel sugere que a divergência morfológica de D. serido é correlacionada com a distância geográfica das populações. A explicação para o padrão observado não é única. Por esta razão, os resultados foram discutidos considerando-se as três principais hipóteses para explicar a evolução do edeago: chave-fechadura, pleiotropia e seleção sexual. Alternativamente, a variabilidade encontrada nos edeagos de D. serido poderia estar relacionada a fatores ambientais, tais como temperatura e/ou cacto hospedeiro.


Drosophila serido Vilela & Sene is a polytypic and cactophilic species with broad geographic distribution in Brazil. The morphology of the aedeagi of eight natural populations of D. serido was analyzed. Based on features of their aedeagi, populations of D. serido were discriminated with an efficiency of nearly 75 percent. The analysis using the Mantel test suggests that the morphological divergence of D. serido is correlated with the geographic distance among populations. There is no single cause to explain the observed pattern; therefore, the results were discussed considering the three main hypotheses to explain the aedeagus evolution: lock and key, pleiotropy and sexual selection. Alternatively, the aedeagus variability of D. serido might be related to environmental causes, such as temperature and/or host cacti.


Subject(s)
Animals , Drosophila/genetics , Genetic Variation , Phenotype
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