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The genus Notiosorex is the only group of shrews in North America with adaptations to arid or semiarid zones. The genus was described with a single variable species, Notiosorex crawfordi , from which 5 new species have since been distinguished. To date, the phylogenetic relationships of Notiosorex species have only been partially analyzed and it is possible that there are still distinct species included within the catch-all of N. crawfordi. Here, we use geometric morphometrics on cranial and mandibular characters of the described extant species, 3 fossil species, and a distinctive population of N. crawfordi as a proxy for an integrated assessment of phylogenetic relationships of all Notiosorex species. Our results indicate that the population from the Altiplano Mexicano is more similar to, yet distinct from, N. villai than it is to N. crawfordi —we describe it as a new species. We also used the resulting tree to reconstruct phylogeographic history within the genus, which suggests that Notiosorex sp. nov. N. villai , N. evotis , and N. tataticuli all diverged allopatrically as populations from the ancestral area that is currently occupied by N. crawfordi (and in the deeper past by the fossil species N. harrisi), and pushed south into the Gulf Coast, the Altiplano, and Baja California within the last 5 million years following the end of the Miocene. [ABSTRACT FROM AUTHOR]

The study of the shape variation in geometric morphometrics has an important limitation known as the Pinocchio effect. The Pinocchio effect produces artifactual variances of the landmarks and implies that it is not possible to know the morphological change structure of an object, other than by dividing the landmark sets and then comparing them. This, however, involves making prior assumptions about the pattern of variation of an object. In this study, we provide a code in R to iterate over a complete set of landmarks and test all possible combinations of landmarks until deliver those landmarks associated with the largest to the smallest morphological changes. We tested this on a sample of 28 landmarks in 143 3D models of human skulls. The results indicated that this process can result in a pooled variance of a subset of landmarks that is an order of magnitude larger than that of several other regions of the skull. This method makes it possible to describe the pattern of variation of any 2D or 3D object represented by fixed landmarks, to distinguish the shape features that have more morphological dispersion, and to avoid any aprioristic assumptions about how the morphological changes of an object behave. [ABSTRACT FROM AUTHOR]

Antecedentes: Las hojas han sido utilizadas para definir secciones en el género Brickellia, lo que permite postular su valor taxonómico en grupos monofiléticos, así como identificar el grado de similitud morfológica entre especies y secciones en un contexto taxonómico y filogenético. Preguntas: ¿Las especies de Brickellia sección Barroetea se pueden diferenciar con las formas de las láminas foliares? ¿La sección se reconoce de las demás secciones del género con base en la forma foliar?, ¿las formas foliares son un rasgo conservado en el género Brickellia? Especies de estudio: Se utilizaron seis especies de la sección Barroetea y 19 especies de otras secciones de Brickellia y géneros relacionados (Ageratina y Carminatia). Métodos: Se realizó un análisis linear discriminante y un filomorfoespacio para conocer las diferencias y evaluar la conservación de la forma foliar. Resultados: Las especies de la sección Barroetea presentaron diferencias significativas a nivel específico, excepto en Brickellia sonorana. Las especies evaluadas de las secciones Barroetea, Brickellia, Coleosanthus, Leptanthodium y Xerobrickellia tienden a formas ovado-deltoideas, excepto Microphyllae donde son reniformes, en Phanerostylis ovadas o elípticas y en Gemmipedium y Kuhnia lineares. El filomorfoespacio muestra un traslape entre las secciones analizadas; las secciones ancestrales muestran un cambio morfológico mayor que las secciones de reciente diversificación y la conservación de la forma foliar no se confirmó estadísticamente. Conclusiones: La mayoría de las especies de Brickellia sección Barroetea se pueden diferenciar entre ellas, pero no de las demás secciones del género Brickellia. Las formas foliares no se conservan en las secciones del género.

Copyright of Revista de la Academia Colombiana de Ciencias Exactas, Físicas y Naturales is the property of Academia Colombiana de Ciencias Exactas, Fisicas y Naturales and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Argentina de Antropología Biológica is the property of Revista Argentina de Antropologia Biologica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The preserved form of all components of the nerve fiber is a prerequisite for the proper conduction of the nerve impulse. various factors can change the shape of nerve fibers. In everyday practice, qualitative histological analysis is the gold standard for detecting changes in shape. Geometric morphometry is an innovative method that objectively enables the assessment of changes in nerve fibers' shape after local anesthetics action. A total of sixty sciatic nerves were used as material, which was intraneural injected with saline solution in the control group (n=30), and a solution of 1.33 % liposomal bupivacaine (n=30) in the test group. After the animals were sacrificed, nerve samples were taken and histological preparations were made. The preparations were first described and examined using a qualitative histological method, after which digital images were made. The images were entered into the MorphoJ program and processed using the method of geometric morphometry. Qualitative histological examination revealed no differences in nerve fibers after intraneurally applied physiological solution and liposomal bupivacaine. Using the method of geometric morphometry, a statistically significant change in the shape of axons was found after intraneurally applied saline solution and liposomal bupivacaine (p=0.0059). No significant differences in histological changes were found after the qualitative histological analysis of nerve fiber cross-section preparations. A statistically significant change in the shape of nerve fiber axons was observed after geometric morphometric analysis of digital images after intraneural application of saline and liposomal bupivacaine. [ABSTRACT FROM AUTHOR]

Geometric morphometry abstracts the shape of organisms by using reference points, quantifies and analyzes the morphological variation of different species. The objective of this work was to determine the population structure of wild bees Apis mellifera L. from Trujillo, Laredo, Casa Grande and Viru, by means of principal component analysis; samples of nurse worker bees were collected from November 2019 to March 2020 and preserved in 70% alcohol, then they were transferred to the Entomology laboratory of the Faculty of Biological Sciences of the National University of Trujillo, the right mesothoracic wings were mounted and images of these were taken in JPG format, with the Samsung J6PLUS cell phone camera calibrated with the Euromex stereoscope. An HP Intel Core i5 laptop was used and a tps file of the images was created using tpsUtil64 version 1.81 software; then with tpsDig2 version 2.32, 19 anatomical reference points were placed, converted into coordinates in a two-dimensional plane and saved in the same file; then, MorphoJ software was used and procrustes and principal component analyses were performed. The first two components were found to explain 30.85% of the cumulative variance, the first with 17.34% and the second with 13.51%, with a significant overlap between the bees of the four locations, there is no significant difference between the negative end of PC1 and the positive end of PC1 according to the deformed wing contour diagrams. Principal component analysis shows that the investigated wild A. mellifera colonies are genetically very homogeneous. [ABSTRACT FROM AUTHOR]

The Central American brocket deer (Mazama temama) is widespread across the Mesoamerican forests, yet it remains largely unknown. Three subspecies are recognized currently within M. temama using pelage coloration as the primary diagnostic character. However, it remains unclear if there is any pattern of morphological variation throughout its distribution. We compared two models of morphological subdivision, namely the traditional subspecies and another based on biogeographic provinces via 2D geometric morphometrics and ecological niche modeling. The second model presented a better fit to the observed variation in cranial shape and size. We found divergence in skull size between individuals from Mexico and Guatemala (northern group) relative to specimens from Honduras, Nicaragua, Costa Rica, and Panama (southern group), the latter being 8% larger than the northern group. Centroid size showed a significant correlation with geographic distance suggesting an isolation-by-distance pattern. Low geographical overlap between the two clusters suggests niche conservatism. Late Pleistocene dispersal from South to Central America and differences in available resources with subsequent isolation due to climatic barriers therefore may have promoted differentiation in size albeit without extensive changes in shape. In this context, the Motagua-Polochic-Jolotán fault system probably plays a key role in promoting morphological differentiation by climatic isolation. Finally, we suggest that M. t. temama (Kerr, 1792) and M. t. reperticia Goldman, 1913 should remain as valid names for the two morphological and ecologically differentiated groups detected here. [ABSTRACT FROM AUTHOR]

Plant–animal interactions constitute some of the most important ecological processes for the maintenance of tropical forests. Bats are the only group of mammals capable of true flight and have been recognized as important dispersers of pioneer and secondary successional plant species. Although progress has been made in the study of Neotropical bats, morphological variation of the wing and its influence on niche separation between species is unknown. We evaluated relationships among habitat structures of selected Colombian tropical dry forest patches, the diet through interaction networks, and wing morphology of 11 species of bats in the Stenodermatinae subfamily (297 individuals) using geometric morphometry in a phylogenetic context. The results indicate that the phylogenetic signal for wing size is greater than for wing shape, thus providing some evidence for evolutionary convergence. Wing shape variation was associated primarily with the distal anatomical tip of the third finger and the joint between the humerus and the radius and ulna. Species with wide, short wings, as in the genus Artibeus had generalist diets and less nested positions within the interaction networks. In contrast, species with elongated and pointed wings, such as Sturnira and Platyrrhinus , had specialized diets and more nested positions within the interaction networks. We argue that wing shape variation may play an important role as a source of interspecific variation leading to food specialization within tropical bat communities. [ABSTRACT FROM AUTHOR]

The foramen magnum is an important topographic opening which connects cranial cavity and spinal canal. The analysis of the bone material established that there are differences in the shape of the foramen magnum between individuals. The aim of this study was to determine sex based on shape and size of foramen magnum using geometric morphometrics method. A study was performed on three-dimensional models (3D models) of 214 human skulls of known sex and known age (141 male skulls and 73 female skulls). The skulls are located at the museum of Medical Faculty, University of Sarajevo. Skulls belong to Bosnian population from the mid-twentieth century. All examined skulls were scanned with a laser scanner to obtain their 3D models. On 3D models of the examined skulls, four landmarks were marked on foramen magnum. Analysis of sex determination was performed using the MorphoJ program. Results of this study showed that there are sex differences in the shape and size of the foramen magnum. Sex determination based on the shape and size of the foramen magnum was showed 65.25 % accuracy for male and 63.01 % accuracy for female using geometric morphometrics method. Examination of the effect of size of foramen magnum on sexual dimorphism of shape of foramen magnum showed a statistically significant effect. Sex determination based just on the shape of foramen magnum using geometric morphometrics method was possible with 62.41 % accuracy for male and 58.90 % accuracy for female on examined sample. Sex differences on shape and size of foramen magnum were found using geometric morphometrics method on three-dimensional models of the examined skulls. The percentage of accuracy was higher for male based on the shape and size of the foramen magnum than for female. [ABSTRACT FROM AUTHOR]

Las especies invasoras representan una amenaza para la mayoría de los ecosistemas en el mundo, sin embargo, los organismos que son capaces de establecerse en áreas diferentes a su zona de origen cuentan con estrategias de historia de vida que les permiten ser exitosas en la colonización. En Colombia se ha reportado un número elevado de especies invasoras, entre las que se encuentra la jaiba espinosa Charybdis hellerii, originaria del Indo-Pacífico, pero llegada a nuestras costas desde el mar Mediterráneo presuntamente en embarcaciones de comercio. Actualmente este cangrejo se ha reportado desde la zona de la alta Guajira hasta el Golfo de Morrosquillo, lo que evidencia su éxito al ser capaz de soportar las diversas condiciones del Caribe colombiano.En el presente estudio se evaluó la variabilidad fenotípica mediante morfometría geométrica, comparando y analizando el caparazón de ejemplares recolectados en diferentes localidades del nororiente y la parte central de la costa Caribe colombiana (La Guajira, Ciénaga Grande de Santa Marta, Santa Marta, Córdoba, Sucre). Con el estudio de esta estructura no se pudo observar dimorfismo sexual, pero sí se estableció (ANOVA; p

Several lines of evidence suggest the existence of two hunter-gatherer home ranges in southern Patagonia during the Late Holocene: an eastern one, focused on the Pali Aike volcanic field, and a western one, located along a relatively longitudinal band that goes from the south of the Argentino Lake to Última Esperanza. While the use of flakes and dacite predominates in the former, blade technology and black shale exploitation is common in the latter. Long-edged stone tools (side-scrapers and knives) on shale blades are also recorded, at low frequency, in the Pali Aike volcanic field and spaces connected to it. Using geometric morphometric techniques, we evaluate whether these tools belong to the same artifact population. Results show no significant morphological differences between the black shale laminar tools according to their discovery area (eastern versus western). Morphological information and other evidence on sizes of laminar tools and availability of black shale, whose main sources are located in the western area, open the discussion on different mechanisms of population interaction involved in the dispersal of these artifacts. [ABSTRACT FROM AUTHOR]

Copyright of Ecosistemas y Recursos Agropecuarios is the property of Universidad Juarez Autonoma de Tabasco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista de Arqueologia is the property of Revista de Arqueologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Evaluamos diferentes subregiones del cráneo para detectar si los cambios en la consistencia de los alimentos producen un efecto en la variación de tamaño y forma. Se analizaron tres transiciones económicas poblacionales y tres poblaciones no transicionales. Se digitalizaron noventa coordenadas de landmarks en 3D en una muestra de 459 cráneos y se analizaron mediante morfometría geométrica. Adicionalmente se estimo la fuerza de mordida para cada grupo. Nuestros resultados indican diferencias de tamaño entre las transiciones y las regiones craneales. Los cambios de forma se concentran en la inserción de los músculos temporal y masetero, que muestran un alargamiento anteroposterior en los grupos de dieta dura en relación con los grupos de dieta blanda. Otros cambios importantes ocurren en el arco cigomático, que es más ancho en los grupos de dieta dura. La fuerza de mordida en general es mayor en los grupos que representan las dietas más duras.

La morfometría lineal y geométrica son herramientas que evalúan la variación morfológica de los individuos de una especie en función del ambiente donde sus poblaciones habitan. El objetivo del estudio fue evaluar la morfología de tres poblaciones de Sceloporus variabilis en tres ecosistemas del centro de Veracruz, México mediante morfometría lineal y geométrica. Se realizaron colectas de ejemplares de S. variabilis en tres ecosistemas: selva alta perennifolia (SAP), selva mediana subperennifolia (SMSP), y bosque mesófilo de montaña (BMM) y se definieron 16 landmark y 10 semilandmark para su análisis con morfometría geométrica. Ocho medidas corporales (longitud hocico-cloaca, longitud de cabeza, ancho de cabeza, alto de la cabeza, longitud del hocico, distancia entre fosas nasales, ancho y largo del cuerpo) para su análisis con morfometría lineal y los valores promedio de éstas se correlacionaron con las variables ambientales (temperatura y precipitación media anual) de cada localidad de colecta, con el fin de evaluar la respuesta de la estructura corporal con respecto a la variación ambiental en los ecosistemas de estudio. Los resultados indican que las poblaciones de S.variabilis presentaron una similitud entre los caracteres morfológicos evaluados tanto con morfometría geométrica como con la lineal, esto quiere decir que el fenotipo de los individuos de S. variabilis es similar, independientemente de las condiciones del ecosistema.

Notiosorex is the only genus of shrews in North America with particular adaptations for arid habitats such as deserts. Five species currently are recognized in the genus, one of which, Notiosorex evotis , lives in deciduous rain forest from northern Sinaloa to the state of Jalisco in México. Notiosorex evotis originally was described as a subspecies of N. crawfordi ; however, it was recently proposed as a valid species based on a discriminant function analysis of craniodental characters. Morphological differentiation between N. evotis populations and sympatric occurrences with N. crawfordi in northern Sinaloa have been recognized. Here, we used a phylogenetic analysis of a mitochondrial gene (Cytb ; 1,140 bp) and the nuclear beta fibrinogen intron 7 (β-fib I7 ; 385 bp), as well as cranial geometric morphometrics, to assess the taxonomic status of N. evotis. We found sequences of N. evotis forming two main subclades: one that includes the populations of the state of Sinaloa, the other including populations of Nayarit and Jalisco. The boundaries between the two groups seem to be related to the ecotonal cline between the Pacific Lowlands province and the Trans-Mexican Volcanic Belt province, which acts as a geographical barrier. The discriminant function analysis revealed clear differences in skull shape between the three species of Notiosorex to the northwest of its distribution. Considering these multiple lines of evidence from our data set, we confirm that N. evotis is a monotypic species. Our results suggest that geometric morphometrics can be used successfully to identify sibling species by shape, especially in groups where determination by craniodental measurements is not possible. [ABSTRACT FROM AUTHOR]

The taxonomy of the South American river dolphins of the genus Inia has been a focus of intense debate. While traditionally it is thought to be composed of a single species with three geographically structured subspecies (Inia geoffrensis geoffrensis , I. g. humboldtiana , and I. g. boliviensis), recent molecular studies have highlighted substantial differentiation, suggesting the existence of two species (I. geoffrensis and I. araguaiaensis). Despite this evidence, the recognition of the specific status of these taxa has been hindered by inconsistent morphological diagnoses. Here, we aim to provide evidence for the morphological differentiation (or lack thereof) between subspecies and putative species. We employ geometrics and traditional morphometrics to measure skull variation to support efforts of integrative taxonomy. Our results show that morphometric diversity within the group is inconsistent with a single taxon. Morphometric evidence supports the traditional differentiation of three distinct morphotypes within the analyzed sample. These morphotypes largely correspond to described subspecies I. g. geoffrensis , I. g. humboldtiana —the latter differing from the former by size—and I. g. boliviensis , which differs from the remaining groups by shape. Furthermore, morphometric data show no differences between I. g. geoffrensis and a newly proposed species, I. araguaiaensis. Given the conservation importance of this genus and the different threats they are subject to, we strongly suggest an urgent integrative taxonomic treatment of the group to better protect these singular cetaceans. [ABSTRACT FROM AUTHOR]

Copyright of Revista Mexicana de Biodiversidad is the property of Universidad Nacional Autonoma de Mexico, Instituto de Biologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Fluting is a technological and morphological hallmark of some of the most iconic North American Paleoindian stone points. Through decades of detailed artifact analyses and replication experiments, archaeologists have spent considerable effort reconstructing how flute removals were achieved, and they have explored possible explanations of why fluting was such an important aspect of early point technologies. However, the end of fluting has been less thoroughly researched. In southern North America, fluting is recognized as a diagnostic characteristic of Clovis points dating to approximately 13,000 cal yr BP, the earliest widespread use of fluting. One thousand years later, fluting occurs more variably in Dalton and is no longer useful as a diagnostic indicator. How did fluting change, and why did point makers eventually abandon fluting? In this article, we use traditional 2D measurements, geometric morphometric (GM) analysis of 3D models, and 2D GM of flute cross sections to compare Clovis and Dalton point flute and basal morphologies. The significant differences observed show that fluting in Clovis was highly standardized, suggesting that fluting may have functioned to improve projectile durability. Because Dalton points were used increasingly as knives and other types of tools, maximizing projectile functionality became less important.We propose that fluting in Dalton is a vestigial technological trait retained beyond its original functional usefulness. [ABSTRACT FROM AUTHOR]

Copyright of Runa: Archivo para las Ciencias del Hombre is the property of Runa: Archivo para las Ciencias del Hombre and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Missing data may occur in every scientific studies. Statistical shape analysis involves methods that use geometric information obtained from objects. The most important input to the use of geometric information in statistical shape analysis is landmarks. Missing data in shape analysis occurs when there is a loss of information about landmark cartesian coordinates. The aim of the study is to propose F approach algorithm for estimating missing landmark coordinates and compare the performance of F approach with generally accepted missing data estimation methods, EM algorithm, PCA based methods such as Bayesian PCA, Nonlinear Estimation by Iterative Partial Least Squares PCA, Inverse non-linear PCA, Probabilistic PCA and regression imputation methods. Landmark counts were taken as 3, 6, 9 and sample sizes were taken as 5, 10, 30, 50, 100 in the simulation study. The data are generated based on multivariate normal distribution with positively defined variance-covariance matrices from isotropic models. In simulation study three different simulation scenarios and simulation based real data are considered with 1000 repetations. The best and the most different result in the performance evaluation according to all sample sizes is the Min (F) criteria of the F approach algorithm proposed in the study. In case of three landmarks which is only the proposed F approach and regression assignment method can be applied, Min (F) criteria give best results. [ABSTRACT FROM AUTHOR]

The joint use of geometric morphometric with three-dimensional models had a boom in recent years in different branches of science. In archeology, the combination of both disciplines has been especially useful for digitizing and studying both fragile pieces and complete archaeological sites. The Tobacco Idol is one of the most important pieces of archeology in Cuba, and yet this piece is very little studied. Taking advantage of the advantages offered by 3D models for the morphometric description of archaeological objects, in this work a morphometric characterization of the Tobacco Idol is carried out from its three-dimensional model. The threedimensional model of the idol was obtained using photogrammetry techniques and, once calibrated, its morphometric characterization was carried out using 46 different measurements, including linear, area and volume measurements. The idol's lateral asymmetry was analyzed using distance maps and compared with an ellipsoid to analyze possible deformations with respect to the geometric shape. The 3D model presented a total of 1.4 million polygons, a volume of 22.27 dm3 and a total area of 53.8 dm2. The asymmetry analysis showed that the region around the face turned out to be the most symmetrical, while the greatest asymmetry was found between the arms and the penis, which is displaced to the left. 95% of the differences found between both halves was less than 8.45 mm, while the maximum absolute distance was 14.42 mm. The comparison with the ellipsoid showed that areas such as the penis, as well as the left arm protrude from the geometric shape because the left region of the idol is slightly more domed than the right. The three-dimensional model presented sufficient quality to be used in this type of work, which endorses the use of photogrammetry for the digitization of archaeological pieces and their morphometric description, in addition to the fact that its digitization means the conservation of the collections for future generations. [ABSTRACT FROM AUTHOR]

Copyright of Spanish Journal of Palaeontology is the property of Socieadad Espanola de Paleontologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

En la decoración parietal de la Tumba Tebana 49, su propietario, Neferhotep, está representado junto con otros actores sociales desempeñando distintas actividades durante su vida terrena y en su proyección póstuma. Puede esperarse que algunas de estas expresiones visuales guarden altos grados de similitud con la realidad, mientras que otras se ajusten a una recreación de potenciales situaciones que ocurrirían a futuro, una vez que hubiese muerto. Al respecto, nos preguntamos si existe alguna clase de diferenciación en la forma de las representaciones que permita individualizar a las personas retratadas, o si sólo interesaba representar a aquellos grupos sociales que debían intervenir en los rituales de enterramiento. Persiguiendo este objetivo, nos proponemos evaluar la existencia de variaciones en la forma de los perfiles de las personas representadas, retomando algunos de los resultados alcanzados en trabajos precedentes. Dichos análisis, efectuados mediante las técnicas de morfometría geométrica, mostraron la existencia de diferencias dependientes del sexo como así también del estatus y/o rango social en los modos de representación de los perfiles de los personajes. Aquí nos interesa evaluar la interrelación de ambas variables y la importancia relativa del sexo (determinado mediante rasgos fisonómicos) en las variaciones morfológicas observadas en los retratos de hombres y mujeres.

Contexto: El proceso de hibridación (africanización) de la abeja europea con abejas de origen africanos es un problema para los apicultores del continente americano, por su alta enjambrazón y defensividad, esta última dificulta en buena medida el manejo de las colonias y ha provocado accidentes en el caso de personas y anímales, lo que hace de la apicultura una actividad riesgosa. En este sentido, se ve la necesidad de mejoramiento genético de la abeja melífera para lo cual es esencial la identificación de subespecies. Objetivo: Evaluar el origen de la abeja mellifera (Apis mellifera), así como el proceso de africanización y dispersión de las abejas africanizadas a través del continente americano y métodos de identificación. Métodos: Se revisaron las bases de datos de Sciencedirect, Google-Scholar, Scopus y NCBI con el empleo de las palabras claves: Apis mellifera, Apis, abejas africanizadas, morfometría geométrica, ADN mitocondrial. Se enfatizó en los artículos de los últimos cinco años. Resultados: Se describen el origen y distribución de la abeja melífera, así como el proceso de africanización y dispersión de la abeja africanizada. Además, se actualiza sobre la evolución de los métodos de caracterización de subespecies de Apis mellifera. Conclusiones: La africanización puede considerarse el proceso más importante en la transformación de las características conductuales y morfológicas de la abeja melífera, las que permitieron su rápida dispersión a través del continente americano. Los métodos de identificación tanto vía materna como paterna son esenciales para conocer posibles procesos de erosión genética y para plantear estrategias de conservación y mejoramiento de las abejas a nivel de cada región.

Asimetria divergent a les plaques de Testudo hermanni (Gmelin, 1789) pures i híbrides L’asimetria fluctuant (AF) es defineix com la presència de diferències subtils entre els costats dret i esquerre dels organismes bilateralment simètrics o les seves parts. Tant els canvis genètics com els ambientals poden incrementar l’AF, que representa la deterioració en l’homeòstasi del desenvolupament de la morfologia adulta a causa d’una disminució en l’estabilitat del desenvolupament. En aquest estudi examinem, mitjançant tècniques de morfometria geomètrica, asimetries en les plaques del plastró en una mostra de 31 individus purs i encreuats de Testudo (T. hermanni hermanni, n = 23 i els seus encreuaments amb T. hermanni boettgeri, n = 8), només femelles. Per a això utilitzem un conjunt de 19 referències anatòmiques. L’ANOVA de Procrustes va indicar una AF significativament més gran en els encreuaments, que a més van mostrar un grau més elevat de plasticitat fenotípica. Els autors concloem que l’encreuament entre aquestes subespècies podria produir un increment en l’homozigositat que seria responsable d’un augment de la inestabilitat del desenvolupament. D’altra banda, disposar de més informació sobre els fenotips dels encreuaments seria de gran interès per a la cria de la tortuga mediterrània amb vista als programes de reintroducció.

In 2004, Xiphopenaeus kroyeri, one of major species in commercial fisheries in Brazil was included in the list of brazilian overfished species and, in 2006, two cryptic species were identified in the Atlantic Ocean by molecular approaches: Xiphopenaeus sp. I and II. In 2019, Carvalho-Batista et al. described both Xiphopenaeus sp. I and Xiphopenaeus sp. II and these species were named X. kroyeri and X. dincao, respectively. This study aimed at performing morphometric analysis in order to identify potential fishing stocks of X. kroyeri sensu strictum along Brazilian coast. The results obtained separate Caravelas, Atafona and Balneário Camboriú from all the other populations studied and showed three groups: Ubatuba, Nova Almeida; Ubatuba, Cananéia; Ubatuba, Santos. These results indicate that the maritime limits practiced in closed seasons along Brazil are embracing the detected morphometric stock boundaries observed for Xiphopenaeus kroyeris.s. [ABSTRACT FROM AUTHOR]

The production of three-dimensional (3D) digital meshes of surface and computed tomographic (CT) data has become widespread in morphometric analyses of anthropological and archaeological data. Given that processing methods are not standardized, this leaves questions regarding the comparability of processed and digitally curated 3D datasets. The goal of this study was to identify those processing parameters that result in the most consistent fit between CT-derived meshes and a 3D surface model of the same human mandible. Eight meshes, each using unique thresholding and smoothing parameters, were compared to assess whole-object deviations, deviations along curves, and deviations between specific anatomical features on the surface model when compared with the CT scans using a suite of comparison points. Based on calculated gap distances, the mesh that thresholded at “0” with an applied smoothing technique was found to deviate least from the surface model, although it is not the most biologically accurate. Results have implications for aggregated studies that employ multimodal 3D datasets, and caution is recommended for studies that enlist 3D data from websites and digital repositories, particularly if processing parameters are unknown or derived for studies with different research foci. [ABSTRACT FROM AUTHOR]

La presencia de diferentes grupos de peces de agua dulce son el resultado de eventos de especiación en la costa ecuatoriana, esto debido a los factores geomorfológicos y variaciones climáticas. La familia Trichomycteridae es un representante de este proceso evolutivo, sin embargo, existen escasos estudios. Este trabajo describió e identifico a los representantes de dicha familia en dos comunas en la cordillera Chongón - Colonche. Las especies identificadas fueron; 30 individuos para Trichomycterus taenia para Dos Mangas y 34 individuos como Trichomycterus cf. taenia para Loma Alta, mediante regresiones lineales se determinó que las relaciones entre las variables analizadas evidenciaron una tendencia lineal con un coeficiente de correlación superior a R = 0.89. Los valores de las pendientes (b) demostraron un crecimiento alométrico negativo (b

The Apis mellifera L. bee is the most used species in the production of honey, pollination of crops and derivatives; however, it has a latent enemy, which always puts at risk the production and bee health that is Varroa sp. (familia) which is the most important ectoparasite of bees in the world. In Peru, few studies have been carried out to reliably determine the species of Varroa present, which is a necessity for making decisions relevant to its control. For this reason the present research sought to determine the species of Varroa through the technique of geometric morphometry. Specimens were collected in apiaries in Tumbes, Piura, Lambayeque and La Libertad. Later, 510 specimens of Varroa sp. were mounted and photographed. Eight Reference Anatomical Points (PAR) were digitized on the ventral surface of the mite. With the obtained data, the Generalized Analysis of Procustes (AGP), Analysis of Main Components (ACP), Analysis of Canonical Variables (AVC) and Analysis of Deformation Grid were made, verifying the significance of these by means of the analysis of Cluster and Kruskal-Wallis, which determined that all the populations of mites present in the north of Peru belong to a single species. Subsequently, the dimensions of the idiosome of the mites were evaluated, finding average lengths and widths of 1.11 mm and 1.70 mm respectively, which corresponds to the species of Varroa desructor Anderson & Trueman (2000). [ABSTRACT FROM AUTHOR]

Copyright of Spanish Journal of Palaeontology is the property of Socieadad Espanola de Paleontologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The jaguarundi (Herpailurus yagouaroundi) has one of the most extensive latitudinal ranges among felids of the Western Hemisphere. Its wide geographic distribution and range of habitats may result in patterns of cranial morphological variation. Thus, we investigated the hypothesis of the existence of morphological ecotypes adapted to specific environments used by the species. The crania of 54 museum specimens from three different ecoregions in Brazil were digitized in ventral, dorsal, and lateral views. No sexual dimorphism was detected. Our hypothesis was supported by the fact that the specimens from the Amazon were significantly larger than those from the Atlantic Forest and Uruguayan savanna. Cranial shape variation between sexes, as well as among ecoregions, was mostly explained by the effect of size. Correlations between geographical distance and cranial shape were not significant. There was a significant correlation between cranium size and latitude, in a pattern that is the reverse of Bergmann's rule, with larger specimens in lower latitudes. The environmental variables positively correlated with cranium size indicated that larger cats occurred in regions with greater temperature and precipitation. Resource availability might be the cause of the observed variation in cranium size, since jaguarundis probably show different prey size preferences along the species distribution range. However, more ecological data for most ecoregions are needed to test the "resource rule" and to fully understand the patterns and causes of cranial variation in this cat. [ABSTRACT FROM AUTHOR]

Introduction: Morphometrics analysis is an efficient and low-cost technique used in studies of sexual dimorphism in turtles. Kinosternon scorpioides scorpioides, scorpion mud turtle, has a wide phenotypic variation, depending on the area of its occurrence. Objective: The objective of this work was to identify the anatomical sexual difference of K. s. scorpioides, adults and hatchlings, through morphometric analysis; and relate the weights of adult animals to environmental factors (temperature and rainfall) in Marajó Island, Brazil. Methods: The sample collection was carried out from March to September 2018, covering both the rainy season (January to July) and the dry season (August to December). For the biometric analysis, 95 adults and 21 hatchlings were used, in which the length and width of the carapace and plastron, height of the shell, and weight were measured (adults only). For the geometric morphometry analysis, 21 adults and 13 hatchlings were used, in which 27 coordinates of anatomical landmarks were inserted in each image of the carapace and 11 in the plastron. Hatchlings were sexed by histology which was enabled by the identification of the ovaries and testicles. Results: The results showed the existence of dimorphism in adults. The plastron and height were higher in females, which had a more rounded carapace than males. This characteristic may be related to the species' sexual strategy, where males impose copulation. Histologically, it was possible to identify the ovaries and testicles in the hatchlings, but there was no anatomical sexual difference, despite the tendency to differentiate in the analysis of carapace PCA. Conclusions: Sexual dimorphism in K. s. scorpioides may play an important role on its reproductive behavior, which is synchronized with environmental events. This fact suggests that the reproductive strategies of this species would be severely affected by changes in the ecosystem. [ABSTRACT FROM AUTHOR]

Introduction: Despite their importance in swimming performance and individual fitness, body shape and size variations in response to water flow velocity remain unknown for most migratory freshwater fishes in the Neotropics. Objective: Test the hypothesis of phenotypic variation in the size and body shape of two species of freshwater fishes that encounter changes in water velocity across their migrations in two rivers that belong to a single Neotropical basin. Methods: Landmark-based geometric morphometrics was used to study variations in body size and shape for the fish species Curimata mivartii and Pimelodus grosskopfii in lotic and lentic habitats of the Colombian Magdalena-Cauca Basin. Results: Individuals of C. mivartii from two lotic habitats were similar in size and both were significantly bigger than those from lentic habitats, whereas individuals of P. grosskopfii were similar in size in both habitats. Both species showed more streamlined bodies in lotic habitats and deeper body shapes in lentic habitats. Conclusions: Both species exhibit phenotypic changes in body shape concordant with previous predictions on morphological variations of fishes. This information is relevant to predict changes in response to environmental heterogeneity, especially those induced by anthropogenic activities that change the water velocity in the river. [ABSTRACT FROM AUTHOR]

Cryptic species, defined as those that are morphologically indistinguishable but phylogenetically distinct, are common in bats and correspond to the majority of newly described species. Such seems to be the case of Glossophaga soricina , a generalist, glossophagine bat that is broadly distributed throughout the Neotropics. Several studies have found high levels of molecular variation within G. soricina , suggesting that it could be a cryptic species complex. Here, we explore data derived from two-dimensional geometric morphometric analyses of cranial characters and their covariation with environmental variables, aiming to test the existence of more than one species grouped within it and to contribute to the knowledge of its variation and evolutionary history. Variation in shape and size of skull and mandible supports the two main mitochondrial lineages reported in previous studies, one corresponding to the east side of the Andes (subspecies G. s. soricina) and the other one corresponding to populations from Mesoamerica and the west side of the Andes, in turn composed of at least three monophyletic and morphologically differentiated taxa. Environmental variables correlate with shape variation and might be responsible for convergences in shape and size between the species with the smallest distributions. Based on the evidence we present in this work we elevate four subspecies to the taxonomic level of species. The correct names for the species of the analyzed complex are: G. soricina (Pallas 1766), G. mutica Merriam 1898, G. antillarum Rehn 1902, and G. valens Miller 1913. [ABSTRACT FROM AUTHOR]

Patterns of selection in South American camelids (Lamini) and their unique demographic history establish the llama and alpaca as remarkable cases of domestication among large herd animals. Skull shape is implicated in many changes reported between wild and domestic taxa. We apply 3D geometric morphometric methods to describe skull shape, form, and size, differences among the four species of Lamini. In so doing, we test if domesticated Lamini exhibit changes similar to those in other domesticated groups: not only in the skull, but also in brain and body size. In contrast to other domesticated artiodactyls, very little change has occurred in domestic alpacas and llamas compared to their wild counterparts. Nevertheless, their differences are statistically significant and include a flatter cranium, inclined palate and increased airorhynchy in the domestics. Selection pressures that contrast with those on other herd animals, as well as recent population bottlenecks, likely have influenced the morphological patterns we note in Lamini. High-resolution 3D morphospace allows skull size, shape, and form (shape + size), to discriminate all four species, with form providing the greatest separation. These results help differentiate morphologically the Lamini, which in nature are distinguished mainly by body size, and provide an additional tool to archaeologists for distinction of wild and domestic remains. Most of our shape analyses suggest a marginally closer relationship between the alpaca and vicuña, to the exclusion of the guanaco, supporting the genetic relationships for this group. The expected brain size change between wild and domestic populations is lower than previously thought, with a 15.4% reduction in llama, and 6.8% reduction in alpaca. This is the lowest reduction in brain size thus far reported among domesticated Artiodactyla. [ABSTRACT FROM AUTHOR]

Miconia rufa is considered an endemic species complex from the eastern Cuban mountains, which includes M. plumieriifolia, a taxonomic decision based on the review of only a few herbarium specimens. Recent collections of this taxa allowed the verification of the foliar shape and size differences between populations of Sierra Maestra and Toa ranges, which indicated the need for a more detailed study regarding this subject. In the current paper, we characterized and morphometrically compared leaves among northeast and southwest groups of eastern Cuba, to provide elements that clarify their delimitation. We analyzed 361 leaves from 45 individuals from different herbaria, the length, maximum width and leaf area were measured, and the shape was described by internal angles, shape indexes, landmarks and Fourier contour descriptors. To characterize environmental conditions of source localities, we extracted bioclimatic models and remote sensing data, a set of variables including mean and annual maximum temperatures, precipitations, altitude, slope, tree cover, NDVI, aridity index and evapotranspiration potential from maps. Populations from northeast and southwest parts were statistically different in length and shape of leaves. Except for the type locality of each name, the rest were not markedly different in environmental conditions, but morphometric differences in leaves were associated with environmental differences. Individuals from the Gran Piedra mountain range show extremes properties. Morphometric characteristics from the type collection of M. rufa and M. plumieriifolia were not representative of all population spatial variability, therefore other studies are required to clarify the origin of these spatial morphometric patterns in the leaves differences of this species complex. [ABSTRACT FROM AUTHOR]

Phyllanthus subcarnosus, which is endemic to Cuba and Hispaniola is the only species in P. sect. Omphacodes. The representatives of Eastern Cuba had been considered a species (P. leonis) independent from those of Western Cuba due to the greater dimensions of their terminal branches, leaves, capsules, seeds and also for their floral characters. However, they are currently considered as a single species. In view of these divergent taxonomic treatments, characterize the morphological diversity of P. subcarnosus is assessed, and its nomenclature, as well as its geographical distribution in Cuba are updated, based on the study of 159 herbarium specimens that represents 59 individual plants, and on the evaluation of 56 vegetative and 63 reproductive characters. The characters that distinguish P. subcarnosus plants in Cuba from its congeners are: hardened cataphylls, elliptical or ovate leaf blade, bisexual cymules, male flowers with three stamens, female flowers with three bifid styles united in a column at the base, and fruits with 6 asymmetrically trigonous seeds. The most important vegetative characters to characterize its variability are the length of the floriferous branches, the number of leaves per floriferous branch and the length of the leaf blade. The nomenclature of the species was updated by clarifying the correct authorship of the name P. subcarnosus is established. The distribution was updated by adding 21 new locations. [ABSTRACT FROM AUTHOR]

Sexual dimorphism in flies has been evidenced in classical morphological characters, but little is known about the differentiation in wing geometry, a multivariate character highly controlled at the genetic level that influences the flight and impacts its life history and can be analyzed through geometric morphometrics. Here, we evaluated sexual dimorphism in the wing geometry of Musca domestica L., a cosmopolitan synanthropic fly. Specimens from Colombia were used for wing mounting, photography, and landmark-based geometric morphometric analysis. We found significant differences between male and female specimens in wing size and shape. Particularly, cross-validated classification based on wing shape resulted in high scores (90%) of correct sex attribution. The influence of wing geometry differences on the flight performance and life history in this species remains unknown. [ABSTRACT FROM AUTHOR]

Introduction: The sea star odontophore is the structure positioned between the paired oral ossicles, with which they articulate through proximal and distal processes. The internal anatomy structures may be used as taxonomic characters for a precise differentiation between species, so it is necessary to describe the structures variation throughout growth. Objective: To describe the odontophore shape and variation of Luidia superba A. H. Clark, 1917 from specimens of the Gulf of California deposited in the Echinoderm National Collection, ICML UNAM. Methods: A total of 735 specimens were examined to describe the external characters, from which 55 selected specimens, within a range of R = 14 mm and R = 210 mm, were dissected to extract the odontophores and analyzed with geometric morphometrics. Results: Scanning electronic microscopy (SEM) images of the odontophores showing the variations in shape throughout growth are presented. Differences in shape between size groups were confirmed with a Canonical Variables Analysis (P < 0.05). Conclusions: There are three main groups in this size ranges where specialization of the stereom can be observed through the ontogenetic series; the variation in shape of the odontophore shown here is a precedent for the use of internal anatomy as new taxonomic characters of identification. [ABSTRACT FROM AUTHOR]

Copyright of Revista Mexicana de Biodiversidad is the property of Universidad Nacional Autonoma de Mexico, Instituto de Biologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Mexicana de Biodiversidad is the property of Universidad Nacional Autonoma de Mexico, Instituto de Biologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

RESUMO Os otólitos são estruturas espécie-específicas de peixes cuja análise morfológica é uma ferramenta eficiente para identificação e discriminação de estoques e/ou populações sujeitas a variações clinais. O presente trabalho buscou elucidar o grau de variação morfológica dos otólitos sagitta do dourado, Coryphaena hippurus Linnaeus, 1758 capturado ao largo da costa sudeste do Brasil pela frota pesqueira sediada no Rio de Janeiro. Os 164 pares de otólitos analisados foram obtidos a partir de amostras coletadas entre fevereiro de 2014 e outubro de 2016. A forma e o contorno dos otólitos sagitta foram caracterizados através de seis descritores (área, perímetro, circularidade, retangularidade, excentricidade e dimensão fractal) e análises de Fourier elíptica (AFE), a partir de imagens dos otólitos. Comparações interanuais dos descritores de formas apontaram diferenças significativas (PERMANOVA p

El estudio del cuarzo como materia prima para la manufactura de instrumentos líticos ha ido aumentando, desarrollándose nuevas estrategias analíticas para comprender las elecciones tecnológicas de los antiguos talladores. En nuestro caso particular, hemos desarrollado una experimentación tendiente a diferenciar los resultados obtenidos mediante talla directa y talla bipolar, comparando con los resultados de los sitios excavados en la Sierra de El Alto-Ancasti, Catamarca, ubicados cronológicamente en la segunda mitad del primer milenio de la era. Nuestro objetivo aquí es el de aportar nuevas vías de estudio con base en los materiales de experimentación y los conjuntos arqueológicos a partir del estudio de variables métricas y el desarrollo de análisis de morfometría geométrica. La principal hipótesis de partida se basa en que las técnicas de talla fueron utilizadas para la obtención de formas base diferentes, para la manufactura de instrumentos particulares. Para ello comparamos los datos métricos de largo, ancho y espesor. El estudio de la morfometría geométrica se centró en el mismo tema, evaluando la presencia de tendencias distintas en las formas base de instrumentos con funcionalidades diferentes.

The extensive diversity in dental form across mammals and its strong relationship with function provides insights into the diet, habitat, and behavior, of both extant and extinct taxa. Understanding the extent of variation in dental morphology across species allows for more accurate identification of fossils and a better ability to infer relationships between form and function and ecology. We examined variation in the size and shape of the first upper molar among the genus Neotoma. We employed elliptical Fourier analysis to quantify differences in the shape of 2D outlines for 23 populations and six species of Neotoma , varying in body size and habitat preference. As expected, molar length is a strong predictor of body size and is significantly and negatively correlated with temperature, particularly in species whose ranges span large latitudinal gradients. We found that differences in molar shape separate species into three general morpho-groups, with no evidence of a phylogenetic signal. While outline analysis could not robustly classify all molars to the species level, it did perform well for Neotoma cinerea , probably because of the greater degree of folding and more acute angling of molar lophs. In contrast, wider lophs with shallower enamel infolding was characteristic of species specializing on softer, more succulent resources (i.e. Neotoma albigula and Neotoma micropus). Neotoma floridana were inaccurately classified to species in the majority of cases, but were the only molars correctly identified to locality 100% of the time, suggesting that dietary specializations at a local level may drive morphological changes within the species as well as across the genus. [ABSTRACT FROM AUTHOR]

This study provides an updated vision of the study of Geometric Morphometrics and its most recent application in ecology and evolutionary biology, covering a wide variation in methodology occurring in the last 5 years since the first version published in the International Journal of Morphology. Geometric Morphometrics is a tool that allows evaluating morphological variations with underlying factors, with a higher sensitivity than traditional morphology, so that minimum changes of morphological variation can be detected. Therefore, it has turned into an outstanding tool to answer questions of comparative biology focused on anatomic characters. At the beginning, it was a tool mainly used to answer taxonomic questions and for differentiation at individual, population or species level. However, in the last years, the number of questions and problematic on which it is applied, has diversified considerably, turning it into a very accurate tool to answer questions of morphological variation in ecologic and evolutionary contexts. Almost half a decade has elapsed since the last revision of the method, so this work is intended to analyze the methodological changes and the new approaches used in Geometric Morphometrics, including a brief introductory guideline to these new methods, their uses and applications. [ABSTRACT FROM AUTHOR]

A través de la morfometría geométrica, este estudio explora la influencia del contexto cronológico y de procedencia en la variabilidad morfológica de 75 anzuelos de concha de Choromytilus chorus provenientes de siete sitios arqueológicos de la comuna de Taltal, en la costa sur del Desierto de Atacama, Chile. Los resultados muestran diferencias significativas en las formas de los anzuelos provenientes de distintos sitios y períodos. El rasgo que explica el mayor porcentaje de variación morfológica es el largo de una de las puntas, seguido por la abertura del anzuelo. Se identifican tres momentos clave en la evolución morfológica de estos artefactos. Entre 8500 y 7500 cal aP aparecen los primeros anzuelos, predominantemente sin vástago y de abertura amplia pero variable. De 7500 cal aP en adelante, la tecnología prolifera y se diversifica: los anzuelos sin vástago y con abertura amplia siguen predominando, pero formas con vástago y abertura media también están presentes en el kit de pesca. Finalmente, entre 5500 y 4500 cal aP el número de anzuelos disminuye, desaparecen las formas circulares y se mantienen las formas con vástago, pero con abertura más estrecha. El caso de estudio de Taltal contribuye a enriquecer el conocimiento sobre la tecnología del anzuelo en concha a lo largo del Pacífico. [ABSTRACT FROM AUTHOR]