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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]

Although dose-response analyses are a fundamental tool in developmental toxicology, few studies have examined the impacts of toxicant dose on the non-genetic paternal inheritance of offspring disease and dysgenesis. In this study, we used geometric morphometric analyses to examine the impacts of different levels of preconception paternal alcohol exposure on offspring craniofacial shape and symmetry in a mouse model. Procrustes ANOVA followed by canonical variant analysis of geometric facial relationships revealed that Low-, Medium-, and High-dose treatments each induced distinct changes in craniofacial shape and symmetry. Our analyses identified a dose threshold between 1.543 and 2.321 g/kg/day. Below this threshold, preconception paternal alcohol exposure induced changes in facial shape, including a right shift in facial features. In contrast, above this threshold, paternal exposures caused shifts in both shape and center, disrupting facial symmetry. Consistent with previous clinical studies, changes in craniofacial shape predominantly mapped to regions in the lower portion of the face, including the mandible (lower jaw) and maxilla (upper jaw). Notably, high-dose exposures also impacted the positioning of the right eye. Our studies reveal that paternal alcohol use may be an unrecognized factor contributing to the incidence and severity of alcohol-related craniofacial defects, complicating diagnostics of fetal alcohol spectrum disorders. [ABSTRACT FROM AUTHOR]

In this study, Taxonomic differences between Microtus guentheri and Microtus hartingi , which are similar in terms of external morphological features, were determined using linear morphometric, geometric morphometric, karyological and molecular analyses methods. Through classical morphometric (mean values) and geometric morphometric analyses of craniodental and mandible characters, influenced by various genetic, developmental, and functional processes, it was found that M. hartingi and M. guentheri exhibited notable differences in both mean linear measurements and shape. The Jackknife in classical morphometric analyses of samples, which underwent molecular and karyological species diagnoses, was higher than 88 % for each character. In geometric morphometric analyses, the Procrustes distance for shape follows the order Ventral < Dorsal < Mandible < M3

ABSTRACT: The neurocranium in birds provides valuable insights into their morphological diversity, including adaptations related to brain size, facial shaping, and environmental factors. This study analyzes the neurocranial shape characteristics and size of chickens with similar genetic backgrounds. By examining the neurocranial shape variation in chickens of the same age and sex, the study aims to understand the factors contributing to morphological diversity within this specific group. 3D geometric morphometrics was used to analyze 235 neurocrania from four chicken breeds. The analysis revealed significant differences in centroid size among the chicken breeds. The largest neurocranium centroid size was found in Sasso chickens., which were statistically separated from Atak-S. Additionally, centroid size effectively differentiates between Lohmann Brown and Lohmann Sandy chicken breeds. The most significant shape variation concerned the width of the rostral part of the frontal bone. However, according to the PC1 value, the shape variation was observed within rather than between groups. Lohmann Sandy chickens exhibited higher variability in neurocranial shape, suggesting greater shape diversity within this breed than others. As for shape analysis, the breeds showed closer similarity to each other. Lohmann Sandy chickens are characterized by positive PC1 value, with the rostral end of the frontal region inclined more ventrally, and a more extensive basioccipital region. Sasso chickens have a more dome-shaped middle part of the frontal region than other breeds. The study also identified the most significant shape variation among the study samples, observed at the rostral part of the frontal bone. These findings contribute to understanding the genetic and environmental influences shaping neurocranial morphology in chickens. Similar studies in different bird species and subspecies offer valuable insights into avian biology and adaptation.

SM, Binashikhbubkr K, Setyawan AD, Md Naim D. 2024. Geometric morphometric divergence of five populations of Pampus argenteus (Euphrasen, 1788) from Malaysian waters. Nusantara Bioscience 16: 1-12. Phenotypic variation in fish may indicate different environmental conditions that affect species' growth and maturation rates and result from genetic factors that allow fish to adapt to different environments. Understanding population structure and dynamics is extremely important for establishing sustainable fisheries. Silver pomfret, Pampus argenteus (Euphrasen, 1788), is an economically important fish species with extensive geographical distribution from the East China Sea to Southeast Asia, Indian Ocean, Arabian Gulf, and the North Sea. It may represent morphologically distinct populations across their range. The main aim of this study is to use geometric morphometric analysis based on physical characteristics to look into the phenotypic diversity of the species across five different populations in Malaysia. Digital images of 260 mature specimens were captured for further analysis. Principle Component Analysis (PCA) and Multivariate analysis (MANOVA) were used in the intra-population analysis based on the transformed distance. At the same time, the Canonical Variance Analysis (CVA) and the Procrustes ANOVA were utilized to determine the inter-population analysis of P. argenteus. The Unweighted Pair Group with Arithmetic Mean (UPGMA) method used to support the analysis has shown that the population is clearly grouped according to homologous body shape. The results show that South, West, and North Coast specimens were grouped while the East Coast and Borneo Island shared in another group. The variations in the body shape of P. argenteus occurred in body depth, caudal region, and head orientation. The findings separated the populations into two main groups representing the marine region to which they belong. This present study is the first report on phenotypic variations of P. argenteus from Malaysian waters utilizing the geometric morphometric method. [ABSTRACT FROM AUTHOR]

Sheep (Ovis aries) play an important role in the economy of Turkey and the Balkan Peninsula due to their use in farming. As a domesticated species, sheep's morphometric and morphological diversity is likely determined by selective breeding practices rather than geographic distribution. This study aimed to analyse four different sheep breed skulls and reveal skull asymmetry using geometric morphometric methods. For this purpose, 2D images of 52 sheep skulls from different breeds were analysed from the dorsal view of the skull, using 28 landmarks. In the comparison of sheep skulls from the dorsal view, the first principal components for directional asymmetry (DA) and fluctuating asymmetry (FA) were 32.98% and 39.62% of the total variation, respectively. Sharri and Ivesi (Awassi) sheep breeds had the broadest distribution of skull shapes among the breeds, while Lara e Polisit was the most conservative breed. DA was used as a measure of biomechanical constraints, and FA was used as an indicator of environmental stress. Consistent with DA, both differences in centroid size and shape between breeds were statistically significant. No differences between males and females related to asymmetry were revealed. Ivesi sheep revealed the highest fluctuating asymmetry. Geometric morphometric methods proved to be a useful tool for distinguishing differences in the shape of the skull of different sheep breeds and also can be useful for taxonomic purposes. [ABSTRACT FROM AUTHOR]

The quantitative genetic relationship between two populations of the fly, Calliphora vicina was studied, specimens of which were collected from some areas of Waist and Southern Iraq. In this study, the geometric morphometric system for wing shape and size was used to detect quantitative genetic variations in the shape, size and area of the right wing of the fly specimens. Central size of the right wing was 1412.4-1423.7 microns for specimens from the Waist and southern regions of Iraq, respectively. The results of the statistical analysis using the F and T tests showed that there were no significant differences in right wing central size between the specimens of the study areas, except for one significant difference found in one of the insect specimens of the southern region (the specimens of the Waist region). It was also noted that there were very few significant differences in the shape and size of the right wing of some insect specimens for that area due to their impact on the different environmental conditions in the areas from which the specimens were collected. [ABSTRACT FROM AUTHOR]

Abiotic factors and hydrological disturbances associated with climatic phenomena are challenges to be overcome by many estuarine resident fish. This study investigates whether periods of intense rainfall and continental discharge associated with El Niño events increased the occurrence of estuarine resident fish at adjacent marine sites and possible changes in their body shape and size when caught in the marine area. We used a long-term time series (1996–2019) of environmental factors and abundance of an estuarine resident fish (Atherinella brasiliensis) and comparisons of their body measurements (morphometry) in a subtropical estuary and its adjacent marine zone. Generalized linear models (GLM) showed that A. brasiliensis abundance increased in the marine zone during periods of higher rainfall associated with moderate and very strong El Niño events in relation to neutral and weak events. The species showed differences in body size between estuarine and marine regions, but no substantial changes related to body shape. El Niño events with higher intensity seem to be influencing the displacement of the larger specimens to the marine surf zone over time. More specifically, hydrological disturbance (intense rainfall and river flow) triggered by El Niño of greater intensity might explain the abundance of A. brasiliensis in the marine area and its high tolerance for salinity changes may explain the maintenance outside its estuarine habitat. These findings may help to understand the mechanisms used by estuarine fish to tolerate environmental stress and changes in their habitats, especially in estuaries subject to climatic disturbances caused by El Niño events that are predicted to become more frequent and intense with global warming. Results suggests that long-term changes in flow regimes trigged by strong climatic phenomena like El Niño might alter estuarine specimens' distribution in the Patos Lagoon Estuary. [ABSTRACT FROM AUTHOR]

Although dose-response analyses are a fundamental tool in developmental toxicology, few studies have examined the impacts of toxicant dose on the non-genetic paternal inheritance of offspring disease and dysgenesis. In this study, we used geometric morphometric analyses to examine the impacts of different levels of preconception paternal alcohol exposure on offspring craniofacial shape and symmetry in a mouse model. Procrustes ANOVA followed by canonical variant analysis of geometric facial relationships revealed that Low-, Medium-, and High-dose treatments each induced distinct changes in craniofacial shape and symmetry. Our analyses identified a dose threshold between 1.543 and 2.321 g/kg/day. Below this threshold, preconception paternal alcohol exposure induced changes in facial shape, including a right shift in facial features. In contrast, above this threshold, paternal exposures caused shifts in both shape and center, disrupting facial symmetry. Consistent with previous clinical studies, changes in craniofacial shape predominantly mapped to regions in the lower portion of the face, including the mandible (lower jaw) and maxilla (upper jaw). Notably, high-dose exposures also impacted the positioning of the right eye. Our studies reveal that paternal alcohol use may be an unrecognized factor contributing to the incidence and severity of alcohol-related craniofacial defects, complicating diagnostics of fetal alcohol spectrum disorders.

Recent advances in imaging technologies, such as intra‐oral surface scanning, have rapidly generated large datasets of high‐resolution three‐dimensional (3D) sample reconstructions. These datasets contain a wealth of phenotypic information that can provide an understanding of morphological variation and evolution. The geometric morphometric method (GMM) with landmarks and the development of sliding and surface semilandmark techniques has greatly enhanced the quantification of shape. This study aimed to determine whether there are significant differences in 3D palatal rugae shape between siblings. Digital casts representing 25 pairs of full siblings from each group, male–male (MM), female–female (FF), and female–male (FM), were digitized and transferred to a GM system. The palatal rugae were determined, quantified, and visualized using GMM computational tools with MorphoJ software (University of Manchester). Principal component analysis (PCA) and canonical variates analysis (CVA) were employed to analyze palatal rugae shape variability and distinguish between sibling groups based on shape. Additionally, regression analysis examined the potential impact of shape on palatal rugae. The study revealed that the palatal rugae shape covered the first nine of the PCA by 71.3%. In addition, the size of the palatal rugae has a negligible impact on its shape. Whilst palatal rugae are known for their individuality, it is noteworthy that three palatal rugae (right first, right second, and left third) can differentiate sibling groups, which may be attributed to genetics. Therefore, it is suggested that palatal rugae morphology can serve as forensic identification for siblings. [ABSTRACT FROM AUTHOR]

Saraphia siamensis gen. nov. & sp. nov. (Acari: Eriophyoidea) from Mammea siamensis (Miq.) T. Anderson in Thailand is described, illustrated. We provide a geometric morphometric analysis based on different geoghraphic populations. Additionally, we report Vasates spondiasiBoczek & Chandrapatya, 1989, a new record from M. siamensis. No visible damaging symptom was observed for both eriophyoid mite species, indicating that they are vagrants on the underside of leaves. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Taibah University Medical Sciences is the property of Elsevier B.V. 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.)

Abstract Background This study aims to determine the hard and soft tissue shape variation and its changes in Class II division 1 malocclusion before and after orthodontic treatment using Geometric Morphometric Analysis. Methods This retrospective study included 141 pre-treatment and near-end treatment lateral cephalometric radiographs of Class II division 1 malocclusion patients aged 16–40 years with a skeletal II pattern (ANB > 4o). 32 landmarks in Cartesian coordinates were created and identified using MorphoJ software to establish a shape analysis. Results The vertical dimensions (hypodivergent to hyperdivergent facial profiles) showed the largest variation in the general shape of hard and soft tissue, followed by the anteroposterior dimensions (mild to severe skeletal II patterns). Variations of lip shape (long to short), lip protuberance (everted to inverted), and nasolabial angle (obtuse to acute) were present. Orthodontic treatment affected the shape of the hard and soft tissue significantly (p

Floral traits are used as signals to attract pollinators and play an important role in species identification and isolation. Nicotiana is a genus with a diverse range of flower morphologies, colours, and pollination systems related to a natural history of hybridization, a driver of speciation in this genus. Nicotiana alata and Nicotiana forgetiana are pollinated by hawkmoths and hummingbirds, respectively, and a putative hybrid population was recently found. This population presents flowers with intermediate phenotypes providing an opportunity to investigate the impact of hybridization on floral trait variation. Here we investigated the floral shape, floral pigments, and nectar traits in a putative hybrid population, hereafter termed atypical populations (AP) compared to phenotypes of allopatric populations of both species. We found a high variation in floral pigmentation in AP plants and observed phenotype segregation in some genotypes. Nicotiana forgetiana and AP plants showed the same flavanol peaks as Nicotiana alata , suggesting the same UV-absorbent phenotype attractive to hawkmoths. The geometric morphometric results showed that the intermediate-coloured flowers had similar floral shape and size to N. alata. Our results suggest that the putative hybrid population would be able to attract the same parental pollinator—hawkmoths and hummingbirds—making backcrossing events possible and attracting other pollinators, such as bees. [ABSTRACT FROM AUTHOR]

Otitis media (OM) is among the most common of childhood illnesses. It has long been hypothesized that children under age two are predisposed to OM due to differences in the anatomy of the Eustachian tube (ET), including the angle of the ET. OM in later childhood is less common but does occur, begging the question, are there shape differences in the ET that persist underlying later occurrences of OM? To answer this question, a novel method, which applied geometric and morphometric shape analysis to landmarks obtained from MRI data, was used. MRI scans were performed on 16 children (5 control, 3 cOME, and 8 rAOM) between 2011 and 2015. Sixteen landmarks representing the shape of the ET, cranial base, and palate were analyzed. The results of a Procrustes ANOVA indicate that the shape of the ET varies significantly (p < 0.01) between the OM and control groups. The shape differences between the OM group and the control are a medial and low attachment site of the tensor veli palatini (TVP) muscle, a posterior and high torus tubarius, and an anteriorly projected palate. These results support previous findings that a relatively horizontal ET is associated with a predisposition for OM. This study used a novel approach to examine anatomical differences in children with and without OM. First, the data set is unique in that it includes MRI scans of children with a confirmed OM diagnosis. Second, the use of MRI scans in craniofacial anatomy OM research is novel and allows for the collection of soft tissue landmarks and the visualization of soft tissue structures. Third, geometric morphometric shape analysis is a statistical method that captures shape differences, offering a more universal picture of nuanced changes within the entire set of landmarks, in contrast to more traditional linear and angular measurements used in prior OM studies examining craniofacial anatomy. [ABSTRACT FROM AUTHOR]

Canonical Wnt signaling plays multiple roles critical to normal craniofacial development while its dysregulation is known to be involved in structural birth defects of the face. However, when and how Wnt signaling influences phenotypic variation, including those associated with disease, remains unclear. One potential mechanism is via Wnt signaling's role in the patterning of an early facial signaling center, the frontonasal ectodermal zone (FEZ), and its subsequent regulation of early facial morphogenesis. For example, Wnt signaling may directly alter the shape and/or magnitude of expression of the sonic hedgehog (SHH) domain in the FEZ. To test this idea, we used a replication-competent avian sarcoma retrovirus (RCAS) encoding Wnt3a to modulate its expression in the facial mesenchyme. We then quantified and compared ontogenetic changes in treated to untreated embryos in the three-dimensional (3D) shape of both the SHH expression domain of the FEZ, and the morphology of the facial primordia and brain using iodine-contrast microcomputed tomography imaging and 3D geometric morphometrics (3DGM). We found that increased Wnt3a expression in early stages of head development produces correlated variation in shape between both structural and signaling levels of analysis. In addition, altered Wnt3a activation disrupted the integration between the forebrain and other neural tube derivatives. These results show that activation of Wnt signaling influences facial shape through its impact on the forebrain and SHH expression in the FEZ, and highlights the close relationship between morphogenesis of the forebrain and midface.

Ultrastructural descriptions of the inner ear of highly sound-dependent mammalian species are lacking and needed to gain a better understanding of the hearing sense. Here, we present the first morphometric descriptions of the sensory cells of the inner ear in the harbor seal (Phoca vitulina), a mammal with broadly sensitive amphibious hearing. Scanning electron micrographs of the apical surface of the outer hair cells (OHCs) and inner hair cells (IHCs) within the organ of Corti were obtained from five individuals and analyzed by linear and geometric morphometrics. Measurements were taken at regular locations along the cochlea. The spiral shape of the seal cochlea contained two and a half turns. The organ of Corti had an average length of 27.7 mm with 12,628 OHCs (12,400-12,900). Six linear morphometric parameters showed significant patterns of change associated with their location within the cochlear spiral. Likewise, these trends were similarly expressed in cell configuration (cell blocks with 57 landmarks in 12 representative cells) revealed by geometric morphometry. Cell configuration varied predictably with position in the cochlea according to clustering analyses and Procrustes ANOVA (F= 25.936, p

Simple Summary: The present study intended to investigate possible variations in body proportions during the growth of five different shark species that inhabit the Sardinian coastal waters (Central-Western Mediterranean Sea). Our results indicate that all of the evaluated species, while not presenting differences between sexes, seemed to show a generally more elongated body and a wider caudal fin when fully grown. This result may indicate a shift in the role that these species play in their environment during their individual growth. Several elasmobranch species undergo shifts in body proportions during their ontogenetic growth. Such morphological changes could reflect variation in diet, locomotion, or, more broadly, in the species' interactions with their environment. However, to date, only a few studies have been conducted on this topic, and most of them focused on particular body regions. In the present study, the ontogenetic growth of five different demersal shark species was investigated by using both traditional linear morphometry of the entire body and shape analysis of the caudal fin. A total of 449 sharks were analysed: 95 little gulper sharks, 80 longnose spurdogs, 103 kitefin sharks, 124 velvet belly lanternsharks, and 47 angular roughsharks. From each specimen, 36 linear morphometric measurements were taken. While a first canonical analysis of principal coordinates ruled out the possibility of different growth patterns between males and females, the same analysis statistically discriminated between small and large individuals in every species based on their morphology. A Similarity Percentage analysis revealed that the most important measurements in distinguishing these two groups were those related to body lengths, indicating that large individuals are more elongated than small individuals. The shape analysis of caudal fins revealed allometric growth during ontogenetic development, with adult individuals having a wider fin (discriminant analysis, p < 0.05). These findings could be related to changes in predatory skills, supporting the hypothesis of a shift in the ecological role that these sharks play in their environment, thus providing new essential information for their conservation. [ABSTRACT FROM AUTHOR]

Neobuxbaumia tetetzo is a columnar cactus whose flowers are visited by the bat species Choeronycteris mexicana and Leptonycteris yerbabuenae. Although both bat species are considered the pollinators of N. tetetzo, the probability of pollination of each bat species has not been estimated. In this study, we determine the relative importance of C. mexicana and L. yerbabuenae as pollinators of N. tetetzo. The probability of pollination was estimated using two different approaches: (i) morphological correspondence between head (linear traits [total head length, snout length, and face height and width]) and cranial traits (shape traits) of bats and flower traits (linear [internal floral tube length including and excluding the nectary, corolla diameter, stamen length, style length, and corolla tube diameter] and shape traits), and (ii) pollen load analyses to estimate the percentage of occurrence (PO) and the pollination probability index (PPI). Our results showed a lack of a significant correspondence between both head and cranial traits of C. mexicana and the flowers of N. tetetzo, and linear morphological correspondence between total head length of L. yerbabuenae and flower length. Pollen loads of C. mexicana were composed by seven different pollen types, its PO and PPI were 41.87 ± 9.53% and 0.29, respectively. Leptonycteris yerbabuenae pollen loads were composed by three pollen types, with a PO of 78.29 ± 13.67% and a PPI of 0.67. Our results suggest that whereas C. mexicana has a low constancy to the flowers of N. tetetzo, L. yerbabuenae has a higher probability of pollination. [ABSTRACT FROM AUTHOR]

The challenges fish face in intraspecific communication has resulted in adaptation in different parts of their sensory system, including the auditory system. Evidence suggests that the sensory capability is specific for each species. The otolith is a part of the auditory system of teleost fish, and plays an important role in maintaining balance and in hearing. According to previous research, the morphological variation of otoliths is a result of a synergy between genetic and environmental factors such as depth, diet, swimming, and substrates. In this research we focused to explain (1) morphological variations of the otolith of gobiid fish as an animal inhabiting both aquatic and terrestrial environments; (2) the use of this morphological variations for distinguishing gobiid fish; and (3) how communication systems adapt to the local environment. The sagittal otoliths of six species of gobiid fish were extracted and described. In the next step, we studied the sagittal otoliths using the geometric morphometrics method and shape indices. The most common characteristics of the sagitta in the studied gobies fish were the median and mesial sulcus and the absence of a clear rostrum and antirostrum. A comparison between the examined methods showed that the geometric morphometric approach was able to detect the subtle differences between gobies species. Moreover, it seems that lifestyle and vision could affect the efficiency of the auditory system, in particular the otolith shape. For example, it seems the specific otolith shape of Periophthalmus waltoni (a species that unlike other fish spends most of its time out of the water) perhaps is a result of adaptation to land and water. [ABSTRACT FROM AUTHOR]

This study examines the shape of scales from eleven fish species belonging to four fish families to infer whether the family, species and the geographic origin of fishes could be determined using scale shape. Site differentiation was analyzed only for the Cyprinidae since from the five species of this family three occurred in New Zealand and two in Turkey. Morphometric analysis was used because it allows standard multivariate analyses while preserving information about scale shape. Generalized Procrustes Analysis was used to analyse the data on scale shape. Principal components scores were submitted to canonical discriminant analysis to determine the efficacy of discrimination by families, species and geographic variants. The significance of classifications was assessed by MANOVA. MANOVA showed differences in the scale shape for the geographic location as well as by families and species. Families, species and geographic variants explained 91.7%, 82.4% and 95.8%, of the variation respectively. Each geographic location was correctly classified in 92.9% for Turkish and 98.4% New Zealand specimens. Fish scale shape was less effective in discriminating species from distantly related members, but better when the discrimination was among fish families, and best between fish scales for the same family but different body shapes. [ABSTRACT FROM AUTHOR]

Extant odontocetes (toothed whales) exhibit differences in body size and brain mass, biosonar mode, feeding strategies, and diving and habitat adaptations. Strong selective pressures associated with these factors have likely contributed to the morphological diversification of their skull. Here, we used 3D landmark geometric morphometric data from the skulls of 60 out of ~ 72 extant odontocete species and a well-supported phylogenetic tree to test whether size and shape variation are associated with ecological adaptations at an interspecific scale. Odontocete skull morphology exhibited a significant phylogenetic signal, with skull size showing stronger signal than shape. After accounting for phylogeny, significant associations were detected between skull size and biosonar mode, body length, brain and body mass, maximum and minimum prey size, and maximum peak frequency. Brain mass was also strongly correlated with skull shape together with surface temperature and average and minimum prey size. When asymmetric and symmetric components of shape were analysed separately, a significant correlation was detected between sea surface temperature and both symmetric and asymmetric components of skull shape, and between diving ecology and the asymmetric component. Skull shape variation of odontocetes was strongly influenced by evolutionary allometry but most of the associations with ecological variables were not supported after phylogenetic correction. This suggests that ecomorphological feeding adaptations vary more between, rather than within, odontocete families, and functional anatomical patterns across odontocete clades are canalised by size constraints. [ABSTRACT FROM AUTHOR]

Abstract Background The Phenice method is a reliable qualitative analysis of the pubis and ischium region of the innominate bone to assess an individual’s sex. Geometric morphometric provides methods of quantitative analysis of the region for identification purposes, which may be affected by environmental changes. This study analysed the Phenice method by utilising 3D (3 dimensional) CT (computed tomography) scans by geometric morphometrics for sex estimation. The CT scans of 231 adult individuals (148 males and 83 females) of the Malaysian population were landmarked by IDAV Landmark software and analysed by MorphoJ and SPSS. Results The first four principal components (PCs) accounted for 41.9% of the total changes when utilising the Phenice method. Widening in pubic symphysis in a U shape with a general widening of the border of the true pelvis, which is typically seen in females, accounted for 21.8% of the eigenvalues. Conclusions It was possible to quantify the changes seen in the ventral arc, subpubic concavity and the medial aspect of the ischio-pubic ramus for sex estimation utilising the Phenice method, and most of the changes were seen in PC1 at the pubic region, which accounted for 21.8%.

The geometric-morphometric method has become a vital tool for examining shape and size variations. The current study analyzed the effect of gamma radiation on wing characteristics of sterile and normal Medflies, C. capitata, on landmark-and outline-based geometric morphometrics. In landmark-based, there were significant differences in weight matrices as shape variable, but the centroid size as size variable was statistically non-significant between the two populations. PCA of the sterile and normal populations manifested a clear distinction from the results. MANOVA further ascertained significant wing shape differences between sterile and normal populations. In the outline-based approach, PCA of the contours revealed that 10 out of the 80 principal components effectively explained shape attributes. The statistical tests were utilized to introduce the significant influence considered in the sterile insect technique (SIT) because, in the long run, these changes may distort the results of SIT project.

The lacked‐teeth pygmy weasel, Mustela aistoodonnivalis Wu & Kao, 1991, was originally described as being from Taibai Mountain and Zhashui county, Shaanxi, China. Subsequently, it was considered a subspecies or synonym of Mustela nivalis. In a faunal survey of northwestern Sichuan, eight specimens of M. aistoodonnivalis were collected. A molecular phylogenetic analysis of one mitochondrial and six nuclear genes clustered the specimens as a distinct clade and not with M. nivalis. Morphologically, the lack of the second lower molar differentiated them from M. nivalis, and genetic distances were typical of discrete species. These analyses confirmed that M. aistoodonnivalis is an independent species in the genus Mustela. [ABSTRACT FROM AUTHOR]

Simple Summary: Foci of Triatoma infestans were found in the states of Rio Grande do Sul and Bahia, Brazil. The objective of the present work is to evaluate the morphometric differences between populations of residual and wild focus of T. infestans through head geometric morphometry. It is possible to show significant morphometric differences between the studied populations. Furthermore, it is possible to establish a morphometric relationship between these populations and to list hypotheses about the distribution and maintenance of residual foci of T. infestans in Brazil. Triatoma infestans is one of the main vectors of Chagas disease in Latin America. Although the species is under control in most Latin countries, it is still necessary to maintain epidemiological surveillance. The present study aims to characterize T. infestans populations from residual foci in Bahia and Rio Grande do Sul, Brazil, comparing them with natural populations in Argentina and Bolivia. For this, we adopt the geometric morphometry of the heads. It is possible to report the morphometric variety of the studied populations. In addition, we show that the size of the heads contributes to the differentiation between populations, while the shape has less power to discriminate groups. Furthermore, we show that some natural populations have morphometric proximity to residual populations, suggesting a relationship between these triatomines. Our data do not support the origin of residual populations but demonstrate the importance of new studies with other techniques to understand the dynamics of distribution and reintroduction of these vectors in Brazilian territory. [ABSTRACT FROM AUTHOR]

Copyright of Kocatepe Veterinary Journal / Kocatepe Veteriner Dergisi is the property of Afyon Kocatepe University, Faculty of Veterinary Medicine 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.)

Simple Summary: Understanding how sexual dimorphism responds to natural and sexual selection is essential to figuring out how intraspecific phenotypic diversity is produced. By comparing the response of two species of lizards inhabiting the same archipelago, we show that sexual dimorphism is a complex phenomenon resulting from the interaction between sexual and natural selection. These two forces act simultaneously, not necessarily in the same direction, and may generate species-specific spatial pattern of morphological variability even in species settled in the same geographic context. The evolution of sexual dimorphism (SD) results from intricate interactions between sexual and natural selections. Sexually selected traits are expected to depend on individual condition, while natural selected traits should not be. Islands offer an ideal context to test how these drivers interact with one another, as the size is a reliable proxy for resource availability. Here, we analysed SD in body size (snout-vent length) and head shape (assessed by geometric morphometric) in two species of lizards (Podarcis muralis and P. siculus) inhabiting the Tuscan archipelago (Central Italy). We found a strong SD variation among islands in both species. Furthermore, in P. muralis emerged some significant correlations between SD and island size, supporting the occurrence of possible effects of individual condition on SD. By contrast, SD in P. siculus followed opposite trajectories than in P. muralis, suggesting that in this species, natural selection could play a major role as a driver of SD. Our findings show that natural and sexual selection can interact in complex ways, and the responses are species-specific. Therefore, spatial patterns of variation in SD may strongly differ among species, even when they settle in the same geographic contest. [ABSTRACT FROM AUTHOR]

Butterflies display remarkable variation in wing shape and size, which is associated with tremendous ecological diversity. In butterflies, wing color patterns have been extensively studied, but wing shape and size diversity is less understood. In the present study, we investigated the altitude-specific wing asymmetry (right and left wings), sexual asymmetry, and wing covariation (proximal-distal and anterior-posterior wing organization) of Tirumala septentrionis (Butler, 1874). Using the geometric morphometric (GMM) method, we discovered that broad and expanded wings were found in lowland areas, whereas long and more rounded slender wings were found in highland areas. Furthermore, the ANOVA analysis, found significant (p < 0.05) altitude-specific shape and size differences in forewings and hindwings of both sexes. Thus, compared to size variations, the shape can be utilized as a valuable tool to distinguish sex (male and female), wing asymmetry (right and left) as well as altitudes (high and lowlands) specific variations of T. septentrionis. Furthermore, we noticed that lowland butterfly population had more asymmetric wings than the highland in the wing asymmetry analysis. We suspected that the unique wing morphology observed in the highland T. septentrionis population favored long-distance flight (indication of a migratory population). In contrast, the lowland population wing morphology indicated a newly colonized butterfly population. In addition to GMM analysis, we documented the FE-SEM wing scale morphology of T. septentrionis collected from two different altitudes. Interestingly, we observed that there is no difference in scale morphology related to altitude variations. Finally, we concluded that altitude-specific variations were observed mainly on wing shape and size, rather than the wing scales. These morphological variations were primarily associated with an adaptive response like migration, host searching, flight energy management and so on. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the general mandibular symphysis (MS) shape variation among Class III skeletal base, using geometric morphometric analysis. Pre-treatment lateral cephalometric radiographs of 254 patients aged 11-40 years old, with Class III skeletal base (ANB <1o) and lower incisor angle (<99o) were included. Nine-landmarks with x and y coordinates were identified on MS using TPSDig2 software, then exported into Morpho J for shape and statistical analysis. Principal component analysis showed that three main shape dimensions with a total variance of 74.6% represented the majority variation of samples. Procrustes Anova showed the shape of MS in Class III skeletal base to be mainly influenced by gonial angle, incisor inclination and sex (P<0.0001). Canonical variate analysis showed that high gonial angle groups had significantly narrower and elongated MS whereas low gonial angle groups had wider, bulbous and rounded MS (P<0.0001). The ratio of alveolar part to basal part was 1:5 in low gonial angle and 2:3 in high gonial angle. Males had significantly taller MS with narrower B point area compared to females (P<0.0001). Retroclined incisors exhibited taller and retroclined alveolar parts (P<0.0001). The shape of MS in Class III skeletal base varied at the alveolar part, basal part or both and it is influenced by gonial angle, incisor inclination and sex. Hence, understanding the shape variation of MS is important to aid orthodontic treatment planning. [ABSTRACT FROM AUTHOR]

Simple Summary: Modern 3D imaging methods offer many scientific disciplines the opportunity to take their results to the next level. Using standard measurement methods, a CT scanner and a 3D scanner, we have established a methodology for using these devices for craniometric measurements. Craniometry is an important means of obtaining information on population quality and its long-term evolution, not only in wildlife species. In the case of these measurements, an important aspect is the accuracy and time efficiency of the methods used. It has been shown that 3D imaging technologies are able to obtain high quality data in comparable time to standard methods. A comparison of methods has proven that both the CT scanner and the 3D scanner can achieve accurate values, measure a larger range of variables, and store digital copies of the object for archiving or future research. The suitability of CT and 3D scanners for craniometric proposes was tested using digital calipers when determining linear measurements, and a measuring cylinder was used for the accuracy of 3D printing of deer antlers obtained by the CT and 3D scanners. The resolution of digitized objects from a 3D scanner ranged from 0.008 mm to 0.122 mm. For mandibular dimensions, a positive deviation (p < 0.01) from the primary control measurement was recorded. The average antler volume measured with the cylinder was 60.47 cm3 at the first measurement, in the case of the CT scanner 61.62 cm3 and for the 3D scanner 64.76 cm3—both technologies exhibit a positive deviation from the primary measurement. Precise sensing and measurements can be used to evaluate the quality and evolution of wildlife populations, create digital museum collections, or to examine in detail certain traits such as antler and horn development or dentition. [ABSTRACT FROM AUTHOR]

Oxynoemacheilus chomanicus is an endemic loach species in Choman River drainage of Kurdistan Province (Iran). In this study we evaluated the morphological variation of body shape among different population of this species from three main tributaries of Choman River; Baneh, Boein and Shooei Rivers. A total of 92 specimens were examined using geometric morphometric method. Using the photographs from the left side of specimens 14 landmarks and 2 semi-landmarks points were selected and analyzed using PCA and CVA methods. Results obtained indicated significant differences between studied populations, especially in head, caudal peduncle and dorsal fin base parts of the fish body.

The neurocranium in birds provides valuable insights into their morphological diversity, including adaptations related to brain size, facial shaping, and environmental factors. This study analyzes the neurocranial shape characteristics and size of chickens with similar genetic backgrounds. By examining the neurocranial shape variation in chickens of the same age and sex, the study aims to understand the factors contributing to morphological diversity within this specific group. 3D geometric morphometrics was used to analyze 235 neurocrania from four chicken breeds. The analysis revealed significant differences in centroid size among the chicken breeds. The largest neurocranium centroid size was found in Sasso chickens., which were statistically separated from Atak-S. Additionally, centroid size effectively differentiates between Lohmann Brown and Lohmann Sandy chicken breeds. The most significant shape variation concerned the width of the rostral part of the frontal bone. However, according to the PC1 value, the shape variation was observed within rather than between groups. Lohmann Sandy chickens exhibited higher variability in neurocranial shape, suggesting greater shape diversity within this breed than others. As for shape analysis, the breeds showed closer similarity to each other. Lohmann Sandy chickens are characterized by positive PC1 value, with the rostral end of the frontal region inclined more ventrally, and a more extensive basioccipital region. Sasso chickens have a more dome-shaped middle part of the frontal region than other breeds. The study also identified the most significant shape variation among the study samples, observed at the rostral part of the frontal bone. These findings contribute to understanding the genetic and environmental influences shaping neurocranial morphology in chickens. Similar studies in different bird species and subspecies offer valuable insights into avian biology and adaptation. [ABSTRACT FROM AUTHOR]

Otitis media (OM) is among the most common of childhood illnesses. It has long been hypothesized that children under age two are predisposed to OM due to differences in the anatomy of the Eustachian tube (ET), including the angle of the ET. OM in later childhood is less common but does occur, begging the question, are there shape differences in the ET that persist underlying later occurrences of OM? To answer this question, a novel method, which applied geometric and morphometric shape analysis to landmarks obtained from MRI data, was used. MRI scans were performed on 16 children (5 control, 3 cOME, and 8 rAOM) between 2011 and 2015. Sixteen landmarks representing the shape of the ET, cranial base, and palate were analyzed. The results of a Procrustes ANOVA indicate that the shape of the ET varies significantly (p < 0.01) between the OM and control groups. The shape differences between the OM group and the control are a medial and low attachment site of the tensor veli palatini (TVP) muscle, a posterior and high torus tubarius, and an anteriorly projected palate. These results support previous findings that a relatively horizontal ET is associated with a predisposition for OM. This study used a novel approach to examine anatomical differences in children with and without OM. First, the data set is unique in that it includes MRI scans of children with a confirmed OM diagnosis. Second, the use of MRI scans in craniofacial anatomy OM research is novel and allows for the collection of soft tissue landmarks and the visualization of soft tissue structures. Third, geometric morphometric shape analysis is a statistical method that captures shape differences, offering a more universal picture of nuanced changes within the entire set of landmarks, in contrast to more traditional linear and angular measurements used in prior OM studies examining craniofacial anatomy.

Landmark-Based Geometric Morphometric Methods were used for the first time to quantitatively assess shape variations of the third epimeral plate (Ep3) of six Gammarus species (G. lordeganensis, G. parthicus, G. pretzmanni, G. pseudosyriacus, Gammarus sp1 and Gammarus sp2.) from five different localities in Iran. Two landmarks and 10 semi-landmarks on the posterior, anterior and inferior margins of the Ep3 were digitized on 78 adult male specimens. Shape diversity of samples and discrimination of all species were analyzed with Principal Components Analysis (PCA) and Canonical Variates Analysis (CVA). The results strongly supported the distinction in the posterior margin of Ep3 shape of the six species, while the inferior margin clearly showed similar morphological structure. A remarkable separation of G. lordeganensis as a distinct group from the rest of the species was found in both CVA and PCA analyses of anterior margin of Ep3 shape, while other species had overlaps with each other. Based on these findings, geometric morphometric data, could be used to identify diagnostic morphological traits. The shape of the Ep3 could be used as an appropriate character for separating closely related amphipod species of the genus Gammarus.

Inle Lake, an ancient lake located in the Shan Plateau of Myanmar, is a biogeographically attractive region with high fish endemism. Some endemic species inhabit the lake as well as the surrounding areas. The genetic and ecological relationships between populations in the lake and surrounding areas provide important insights into the process underlying ichthyofaunal formation in Inle Lake. In this study, the authors focused on red dwarf rasbora Microrasbora rubescens, an endemic genus and species in this region, and estimated its population structure and evolutionary scenario based on genome‐wide polymorphism, mtDNA and geometric morphometric analyses using samples from Inle Lake and three areas surrounding the lake. The results showed that M. rubescens comprises at least three genetically divergent lineages (Inle, Heho and Hopong) with distinct geographic structures consistent with nuclear and mtDNA data. In contrast, there was no clear regional differentiation in morphology. The divergence time estimation based on mtDNA suggests that the Hopong lineage diverged at 2.7 Ma and the Inle and Heho lineages diverged at 1.9 Ma – consistent with the nuclear DNA results. The deep divergence observed in the endemic species supports the ancient history of ichthyofaunal development in this region. The distinct regional differentiation and morphological conservatism of this species might have been shaped by niche conservatism in stagnant water environments that limit dispersal and morphological diversification. Future comprehensive genetic and morphological analyses and comparisons for other native species should reveal the geographic and ecological processes that shaped the ichthyofauna in this region. [ABSTRACT FROM AUTHOR]

The bonnethead Sphyrna tiburo is a wide-spread, small species of coastal hammerhead shark with a long history of taxonomic uncertainty, including, according to some authors, disjoint subspecies in the western Atlantic and eastern Pacific oceans. The present study investigates the level of morphometric and genetic variation within the Sphyrna tiburo complex throughout most of its distributional range including the western Atlantic, the Gulf of Mexico, the Caribbean, and the eastern Pacific. A morphometric study, including a comparison of ampullary densities, and a molecular analysis of two mitochondrial genes, was performed. We analyzed variation in cephalofoil shape between and within lineages, based on landmarks and Fourier analysis of the silhouettes. All tests delineated discrete morphological groups, including differences of ampullae density for those lineages in which this information could be unambiguously assessed. Both morphometric and molecular analysis support the existence of three different evolutionarily significant units (two in the Atlantic: one northern and one south-central, and a third in the eastern Pacific) that deserve specific taxonomic status. We urge a deep taxonomic review of this complex to gather biological data on each lineage and develop adequate independent conservation strategies and actions to protect the various evolutionary units. [ABSTRACT FROM AUTHOR]

(1) Background: Oaks have achieved notoriety for sufficient levels of sympatric species richness allowing hybridization, thus generating substantial phenotypic variation. Leaf fluctuation asymmetry is an important attribute, as it reflects not only genetic variability but also species buffering capacity. (2) Methods: We investigated the phenotypic diversity of four-oak species (Quercus acutissima, Q. variabilis, Q. fabri, and Q. serrata var. brevipetiolata) using leaf geometric morphometric analysis. Eight leaf morphological indicators (length, width, perimeter, area, left and right areas, areal ratio, and normalized symmetry index) were used to determine the hybridization level, whereas bilateral symmetry indicators were used to assess species environmental adaptation; (3) Results: Phenotypic variation ranged from 1.54 to 29.35 folds and significantly diverged among the studied species. Taxonomically species in Section Quercus (Q. fabri and Q. serrata var. brevipetiolata) are lower than those in Section Cerris (Q. acutissima and Q. variabilis) with good bilateral symmetry. The bilateral symmetry index of Q. variabilis had a larger range of variation, indicating better environmental adaptability; (4) Conclusions: We presume that species in Section Quercus with less leaf fluctuation asymmetry have a high level of genetic heterozygosity; however, this assumption requires further verification. The observed phenotypic diversity reflects a combination of environmental and genetic factors. [ABSTRACT FROM AUTHOR]

Cephalanthera, Limodorum and Neottia, which are known as primitive orchids, are rhizomatous orchids and commonly distributed in Turkey. This study aims to investigate orchid seed variation between some representatives of Neottieae, Cephalanthera rubra, Limodorum abortivum, Neottia nidus-avis, and Neottia ovata, naturally distributed in Turkey by using geometric morphometric analyses based on 2-dimensional landmarks. For this purpose, a total of 95 specimens were evaluated and photographed using scanning electron microscopy. Using software, 12 homologous landmarks were obtained to reflect the main aspects of the seed shape. Species were compared with various statistical methods by calculating the data obtained from shape and size variables with the Procrustes method. The difference in both size and shape were significant between the species. Shape differences were most prominent in the chalazal and micropylar regions of the seed as well as the whole seed width. Discriminant analysis and cross-validation scores were a highly powerful to distinguish the species with scores ranging from 60% to 88%. Regression analyses also revealed allometric effect of the size on seed shape with a similar trend across species. Based on current results, geometric morphometric analysis is encouraging in the research of structural variation within plant parts. The present study is also significant in terms of the widespread use of such studies in the field of botany, especially in the context of systematic or functional morphology. [ABSTRACT FROM AUTHOR]

Abstract Identifying the molecular mechanisms facilitating adaptation to new environments is a key question in evolutionary biology, especially in the face of current rapid and human‐induced changes. Translocations have become an important tool for species conservation, but the attendant small population sizes and new ecological pressures might affect phenotypic and genotypic variation and trajectories dramatically and in unknown ways. In Scotland, the European whitefish (Coregonus lavaretus) is native to only two lakes and vulnerable to extirpation. Six new refuge populations were established over the last 30 years as a conservation measure. In this study, we examined whether there is a predictable ecological and evolutionary response of these fishes to translocation. We found eco‐morphological differences, as functional traits relating to body shape differed between source and refuge populations. Dual isotopic analyses suggested some ecological release, with the diets in refuge populations being more diverse than in source populations. Analyses of up to 9117 genome‐mapped SNPs showed that refuge populations had reduced genetic diversity and elevated inbreeding and relatedness relative to source populations, though genomic differentiation was low (FST = 0.002–0.030). We identified 14 genomic SNPs that showed shared signals of a selective response to translocations, including some located near or within genes involved in the immune system, nervous system and hepatic functions. Analysis of up to 120,897 epigenomic loci identified a component of consistent differential methylation between source and refuge populations. We found that epigenomic variation and genomic variation were associated with morphological variation, but we were not able to infer an effect of population age because the patterns were also linked with the methodology of the translocations. These results show that conservation‐driven translocations affect evolutionary potential by impacting eco‐morphological, genomic and epigenomic components of diversity, shedding light on acclimation and adaptation process in these contexts.

Several elasmobranch species undergo shifts in body proportions during their ontogenetic growth. Such morphological changes could reflect variation in diet, locomotion, or, more broadly, in the species’ interactions with their environment. However, to date, only a few studies have been conducted on this topic, and most of them focused on particular body regions. In the present study, the ontogenetic growth of five different demersal shark species was investigated by using both traditional linear morphometry of the entire body and shape analysis of the caudal fin. A total of 449 sharks were analysed: 95 little gulper sharks, 80 longnose spurdogs, 103 kitefin sharks, 124 velvet belly lanternsharks, and 47 angular roughsharks. From each specimen, 36 linear morphometric measurements were taken. While a first canonical analysis of principal coordinates ruled out the possibility of different growth patterns between males and females, the same analysis statistically discriminated between small and large individuals in every species based on their morphology. A Similarity Percentage analysis revealed that the most important measurements in distinguishing these two groups were those related to body lengths, indicating that large individuals are more elongated than small individuals. The shape analysis of caudal fins revealed allometric growth during ontogenetic development, with adult individuals having a wider fin (discriminant analysis, p < 0.05). These findings could be related to changes in predatory skills, supporting the hypothesis of a shift in the ecological role that these sharks play in their environment, thus providing new essential information for their conservation.

Copyright of Harran University Journal of the Faculty of Veterinary Medicine / Harran Üniversitesi Veteriner Fakültesi Dergisi is the property of Harran University, Faculty of Veterinary Medicine 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.)

Ophiuroidea are one of the most diverse classes among extant echinoderms, characterized by their flexible arms composed of a series of ossicles called vertebrae, articulating with each other proximally and distally. Their arms show a wide range of motion, important for feeding and locomotion, associated with their epizoic and non‐epizoic lifestyles. It remains to be explored to what degree the phenotypic variation in these ossicles also reflects adaptations to these lifestyles, rather than only their phylogenetic affinity. In this study, we analyzed the 3D shape variation of six arm vertebrae from the middle and distal parts of an arm in 12 species, belonging to the intertidal, subtidal and bathyal zones and showing epizoic and non‐epizoic behaviors. A PERMANOVA indicated a significant difference in ossicle morphology between species and between lifestyles. A principal component analysis showed that the morphology of epizoic ophiuroids is distinct from non‐epizoic ones; which may reflect variation in arm function related to these different lifestyles. The Phylogenetic MANOVA and phylogenetic signal analysis showed that shape variation in the vertebral articulation seems to reflect ecological and functional adaptations, whereas phylogeny controls more the lateral morphology of the vertebrae. This suggests a convergent evolution through ecological adaptation to some degree, indicating that some of these characters may have limited taxonomic value. [ABSTRACT FROM AUTHOR]

Variations in the shape and elemental microchemistry of sagittal otoliths in Channapunctatus (Bloch, 1793) populations of three different rivers (Gomti, Ganga and Ken) of Gangetic basin sampled at three geographically distant locations (Lucknow, Kanpur and Banda) were analyzed. In this study, otolith shape was analyzed using shape indices, geometric morphometrics and Fourier analysis and tested through univariate and multivariate statistical procedures. 3 shape indices namely circularity, roundness and rectangularity out of 6 were significantly different in ANOVA (p < 0.05) between the three population groups. Principal component analysis of shape variables in geometric morphometrics and normalized elliptical Fourier descriptors (NEFDs) accounted for 82.25% and 80.10% of total variance respectively. Visualization of shape variation explained by principal components was depicted in the form of shape deformation grids (relative warps) and otolith contour reconstruction. The elemental concentrations in the otoliths of the three rivers also differed, and elements Sr and Ba, Mn and Pb, and Fe were significantly higher (ANOVA, p < 0.05) in the otoliths of river Ken, Gomti and Ganga respectively. Discriminant function analysis (DFA) of the shape variables, NEFDs and otolith elemental concentration clearly differentiated the otoliths of different rivers in scatter plots with isolated distant population groups and 100% classification of all the specimens into their respective river population. The study indicated regional variations in the shape and otolith microchemistry and also that fish from different rivers lived in different environmental conditions. These variations in the present study might be due to geographical isolation and river fragmentation due to the change in the habitat that limits fish movements. Thus, C. punctatus of river Gomti, Ganga and Ken sampled at Lucknow, Kanpur and Banda districts respectively existed as three different phenotypic stocks. This study is useful for the development of effective plans for sustainable fisheries management with the aim of conservation of this economically exploited fish in the Ganga basin. [ABSTRACT FROM AUTHOR]