Geometric Morphometric Methods Research Articles

Testing the accuracy of 3D automatic landmarking via genome-wide association studies.

Various advances in 3D automatic phenotyping and landmark-based geometric morphometric methods have been made. While it is generally accepted that automatic landmarking compromises the capture of the biological variation, no studies have directly tested the actual impact of such landmarking approaches in analyses requiring a large number of specimens and for which the precision of phenotyping is crucial to extract an actual biological signal adequately. Here, we use a recently developed 3D atlas-based automatic landmarking method to test its accuracy in detecting QTLs associated with craniofacial development of the house mouse skull and lower jaws for a large number of specimens (circa 700) that were previously phenotyped via a semiautomatic landmarking method complemented with manual adjustment. We compare both landmarking methods with univariate and multivariate mapping of the skull and the lower jaws. We find that most significant SNPs and QTLs are not recovered based on the data derived from the automatic landmarking method. Our results thus confirm the notion that information is lost in the automated landmarking procedure although somewhat dependent on the analyzed structure. The automatic method seems to capture certain types of structures slightly better, such as lower jaws whose shape is almost entirely summarized by its outline and could be assimilated as a 2D flat object. By contrast, the more apparent 3D features exhibited by a structure such as the skull are not adequately captured by the automatic method. We conclude that using 3D atlas-based automatic landmarking methods requires careful consideration of the experimental question.

The talar morphology of a hypochondroplasic dwarf: A case study from the Italian Late Antique period

AbstractThis project aims to test whether geometric morphometric (GM) and trabecular analyses may be useful tools in identifying talar characteristics related to hypochondroplasia. We quantified the external and internal talar morphology of a hypochondroplasic dwarf (T17) from Modena (northern Italy) dated to the sixth century AD. External talar morphology of T17 was compared with a broad sample of modern human tali (n = 159) using GM methods. Additionally, a subsample of these tali (n = 41) was used to investigate whole talar trabecular changes in T17. Our results show that GM and trabecular analyses identify a combination of traits linked to the dwarfing disorder of hypochondroplasia. These traits include decreased scaled talar dimensions compared with normal‐sized individuals, presence of an accessory antero‐lateral talar facet, high bone volume fraction, and high anisotropy values throughout the entire talus. In our case study, hypochondroplasia does not appear to substantially modify external talar morphology probably due to the fast growth of the talus. We suggest that small talar dimensions are associated with hypochondroplasia. An antero‐lateral talar facet may result from the talus and calcaneus coalition (i.e., talocalcaneal abnormal bridging) possibly related to an everted foot posture that was limited by overgrowth of the fibula. We suggest that high talar trabecular density and strut orientation provide insights into pathological development of the trabecular plates in T17. Finally, our study suggests that high talar trabecular density and strut orientation, and small talar dimensions, may be added as possible concomitant talar hallmarks for hypochondroplasia.

Larval clypeus shape provides an indicator for quantitative discrimination of species and larval stages in Japanese diving beetles Cybister (Coleoptera: Dytiscidae)

Morphological shapes of the larval clypei of seven Cybister diving beetles (Coleoptera: Dytiscidae) from Japan—namely C. brevis Aubé, 1838; C. chinensis Motschulsky, 1854; C. lewisianus Sharp, 1873; C. limbatus (Fabricius, 1775); C. rugosus (Macleay, 1825); C. tripunctatus lateralis (Fabricius, 1798); and C. sugillatus Erichson, 1834—were investigated using landmark-based geometric morphometrics (GM). Younger instar larvae possess clypei with smaller centroid sizes than older larvae in all species. Distinct morphological changes in clypeus are also observed during larval growth. Canonical variate (CV) analysis indicated that CV1 (53.5%) has the most contributing factor explaining shape variations representing clypeus length from anterior to posterior margin. Younger larvae have longer clypei than older ones in all species. Leave-one-out cross-validation indicates that larval clypeus morphology can identify species with greater than 90% accuracy. According to cluster analysis, clypeus shape can also categorize the same species with 99.8% for the first instar larvae and 100% accuracy for the second and third instars. Thus, the GM method can accurately identify species and developmental stages of larvae among the seven Cybister species.

How to get rid of diploid bumblebee males – variability in wing size and shape does not allow within‐colony ploidy discrimination

AbstractThe bumblebee Bombus terrestris L. (Hymenoptera: Apidae) is an effective pollinator of both wild and cultivated plants and essential for the pollination of various important greenhouse crops. Because of its sex determination mechanism, homozygosity of the complementary sex determination (csd) locus due to inbreeding causes fertilized eggs to develop into diploid males, which represent a serious disadvantage for the colonies as their presence decreases colony growth and survival. The identification of diploid males is thus important from both ecological and economic points of view. In the present study, we applied the geometric morphometrics method on wing shape and size of B. terrestris diploid and haploid males at overall and intra‐colony levels to investigate wing changes between the two groups. We found that changes in wing shape concerned almost all cells investigated and male diploidy resulted in a narrower and slightly longer configuration. In addition, diploid male wings presented a very high variation both in size and shape, likely due to sub‐optimal temperature of incubation and food availability during their larval development. This strong variation of diploid male wings makes the ploidy discrimination by wing geometric morphometrics inaccurate based on small reference samples at the intra‐colony level even with allometric data correction, whereas it is accurate (precision >90%) at the overall level, in which sample size is high enough (i.e., 500 individuals). Therefore, our results indicated the need to create a large dataset to allow the analysis of few samples, as is the case with studies of wild bumblebee populations, small rearing companies, or preserved museum specimens. For this reason, we provide a large database of B. terrestris wing Procrustes coordinates (500 samples) to the bumblebee scientific community for use in the analysis of the determination of diploid male individuals.

The contribution of ontogenetic growth trajectories on the divergent evolution of the crocodylian skull table.

To explore shape variability among crocodylian skull tables, an analysis using geometric morphometric methods is conducted with the inclusion of extant and fossil taxa. Skull tables are variable and the differences likely play a role in hydrodynamics, species recognition, and biomechanical adaptations. Comparisons of allometric change within taxa are explored revealing that adults significantly diverge from juvenile skull table morphologies in most species and these changes happen in a stereotyped way. In all analyses, adults of the smallest extant taxa plot alongside the juveniles of related taxa and heterochrony may explain the maintenance of these morphologies into adulthood. When landmarks representing the supratemporal fenestrae are included, longirostrine taxa are broadly separated from one another due to variation in the size of the supratemporal fenestrae. The hypotheses of previous studies suggesting that the size of the supratemporal fenestrae is influenced by snout length-with longer snouts corresponding to larger fenestrae-must be re-evaluated. Although species of the crocodyloids Tomistoma and Euthecodon approach or exceed the length of the snout in gavialoids, their supratemporal fenestrae are proportionally smaller-this suggests a phylogenetic constraint in crocodyloids regardless of snout length.

Medfly Phenotypic Plasticity as A Prerequisite for Invasiveness and Adaptation

The hypothesis of this study was that different plant hosts of the medfly Ceratitis capitata may cause variability as a prerequisite for its invasiveness. The main objective was to determine population variability based on medfly wing shape in three favorable medfly host plants (peach, fig and mandarin) from different agroecological growing areas with different pest management practices, and to evaluate phenotypic plasticity as a basis for future expansion into new areas and new hosts. Using geometric morphometric methods across 14 specific landmarks on the medfly wings, 10 populations were tested from infested peach, fig and mandarin fruits, as well as laboratory-grown sterile populations. The studies led to the following main findings: (1) all of the medfly populations that were studied exhibited sexual dimorphism in wing shape; (2) the hosts in which the medfly develops influence wing shape and condition its variability; (3) there is significant variability between laboratory mass-reared sterile and wild individuals in male and female populations; (4) a high phenotypic plasticity of medfly populations was observed along the study sites. Even the low but clearly detected variability between different agroecological conditions and localized variability indicate genotypic stability and high phenotypic plasticity, which can be considered as a prerequisite for medfly invasiveness and dispersal to new areas.

Unique foot posture in Neanderthals reflects their body mass and high mechanical stress

Neanderthal foot bone proportions and morphology are mostly indistinguishable from those of Homo sapiens, with the exception of several distinct Neanderthal features in the talus. The biomechanical implications of these distinct talar features remain contentious, fueling debate around the adaptive meaning of this distinctiveness. With the aim of clarifying this controversy, we test phylogenetic and behavioral factors as possible contributors, comparing tali of 10 Neanderthals and 81 H. sapiens (Upper Paleolithic and Holocene hunter-gatherers, agriculturalists, and postindustrial group) along with the Clark Howell talus (Omo, Ethiopia). Variation in external talar structures was assessed through geometric morphometric methods, while bone volume fraction and degree of anisotropy were quantified in a subsample (n = 45). Finally, covariation between point clouds of site-specific trabecular variables and surface landmark coordinates was assessed. Our results show that although Neanderthal talar external and internal morphologies were distinct from those of H. sapiens groups, shape did not significantly covary with either bone volume fraction or degree of anisotropy, suggesting limited covariation between external and internal talar structures. Neanderthal external talar morphology reflects ancestral retentions, along with various adaptations to high levels of mobility correlated to their presumably unshod hunter-gatherer lifestyle. This pairs with their high site-specific trabecular bone volume fraction and anisotropy, suggesting intense and consistently oriented locomotor loading, respectively. Relative to H.sapiens, Neanderthals exhibit differences in the talocrural joint that are potentially attributable to cultural and locomotor behavior dissimilarity, a talonavicular joint that mixes ancestral and functional traits, and a derived subtalar joint that suggests a predisposition for a pronated foot during stance phase. Overall, Neanderthal talar variation is attributable to mobility strategy and phylogenesis, while H. sapiens talar variation results from the same factors plus footwear. Our results suggest that greater Neanderthal body mass and/or higher mechanical stress uniquely led to their habitually pronated foot posture.

Quantifying Inter- and Intrasexual Head-Shape Polymorphism in Eurycea cf. wilderae (Blue-Ridge Two-Lined Salamanders)

Distinct morphological differences between and within sexes may reflect reproductive behaviors that have evolved under natural and sexual selection. In some members of the Eurycea bislineata (Two-Lined Salamander) species complex, inter- and intrasexual variation in head morphology result from secondary sexual characters used in locating, courting, and guarding mates. In populations of Eurycea cf. wilderae (Blue-Ridge Two-Lined Salamander), males possess one of two suites of morphological traits corresponding to alternative reproductive tactics. “Searching” males appear to be adapted for locating and courting females in terrestrial habitats and are characterized by the seasonal development of mental glands, protruding premaxillary teeth, and elongate cirri. “Guarding” males appear to be adapted for aggressively guarding females in aquatic habitats, lack all three aforementioned traits, and are instead characterized by seasonally enlarged jaw musculature. Traditionally, males have been categorized by treating these traits as binary (i.e., present or absent), but this fails to capture any continuous variation. Here, we evaluated the utility of geometric morphometric methods to quantify and describe differences in head morphology among female, searching male, and guarding male E. cf. wilderae. In the left-lateral view, we found significant pairwise differences among all three morph–sex groups. In the ventral view, we found significant pairwise differences between searching males and guarding males and between searching males and females, but not between guarding males and females. Deformation grids clearly demonstrated the enlarged jaw musculature of guarding males and wider, flatter rostrum of searching males. Our results demonstrate utility of geometric morphometric methods for describing head shape differences among these alternative reproductive tactics and provide baseline data for future studies of spatial and temporal variation.

Characteristics of the Donkey's Dorsal Profile in Relation to Its Functional Body Condition Assessment.

Simple SummaryEven though animal posture is known to reflect an emotional state, the presence of chronic postures associated with poor welfare has already been investigated in horses. Measuring, quantifying, and comparing postures requires an application of an objective tool, such as geometric morphometrics. This study aimed to use geometric morphometrics to characterize the dorsal profile of donkeys in relation to their individual features. Forty donkeys were photographed and characterized using the body condition score (BCS), fatty neck score (FNS), dental condition score (DCS), sex, and breed. Then, photographs were analyzed using geometric morphometrics and the differences in dorsal profile between the examined criteria were tested. Within the entire set of donkey dorsal profiles, deformation related to BCS and FNS was observed. FNS measurement seems to have the strongest influence on a donkey’s dorsal profile among the examined criteria. Concluding, the donkeys’ body condition affects their dorsal profile, and both FNS and BCS measurements should be considered when the donkeys’ dorsal profiles are investigated. However, to evaluate the link between the dorsal profile and the welfare state of donkeys, more studies are required.As the breeding of donkeys has increased due to different types of use, welfare evaluation importance increases. This equid’s welfare state has been described using body condition indicators and the geometric morphometrics method. However, the dorsal profile has not yet been assessed in donkeys. In this study, the body condition score (BCS), fatty neck score (FNS), dental condition score (DCS), sex, and breed were used as criteria of dorsal profile deformations. Photographs of 40 donkeys were analyzed using geometric morphometrics. Within the entire set of dorsal profiles, the variance of the first three principal components (PCs) was PC1 = 37.41%, PC2 = 23.43%, and PC3 = 13.34%. The dorsal profiles displayed deformation as an effect of FNS and BCS on size (FNS p = 0.012; BCS p = 0.024) and shape (FNS p < 0.0001; BCS p < 0.0001), rather than as an effect of DCS (p < 0.0001), sex (p = 0.0264), and breed (p < 0.0001) only on shape. The highest distances among the categories (Mahalanobis distances: MD ≥ 13.26; Procrustes distances: PD ≥ 0.044) were noted for FNS. The lowest distances were noted between jennets and males (MD = 4.58; PD = 0.012) and between BCS 1 and BCS 2 (MD = 4.70; PD = 0.018). Donkeys’ body condition affects their dorsal profile and both FNS and BCS measurements should be considered when a donkey’s dorsal profile is investigated.

Can geometric morphometrics and traditional methods work for evaluation of body shape plasticity of exotic fishes? A case study of topmouth gudgeon, Pseudorasbora parva (Teleostei: Gobionidae)

Introduction of species outside their native distribution ranges, followed by population establishment and becoming an invasive element, has been a common task and a controversial issue in the last century. The topmouth gudgeon Pseudorasbora parva is a gobionid fish native to southeast Asia, with a high dispersion potential, which succeeded in spreading out in many countries of Eurasia and north Africa including Iran during the almost 50 years. In this study, we are addressing the following research questions: (1) how do fish morphology differ in different water bodies by applying traditional, and geometric morphometric methods? (2) does morphology of P. parva show previous molecular-phylogenetic research based on mtDNA? Results revealed that traditional morphometric characters do not demonstrate a high phenotypic variation among 20 populations of P. parva collected from nine basins/river drainages. The cluster analysis of Euclidean distances among groups of P. parva populations (nine basins/river drainages) revealed segregation of three populations (Harirood, Esfahan and Mashkid basins). Based on the genetic background and colonisation history of P. parva using the mitochondrial DNA control region (806 bp) and a cytochrome c oxidase subunit I barcode database (615 bp), presence of three matrilineal haplotypes belonging to two distinct lineages; (1) a widespread lineage with a common haplotype found throughout the country and one exclusive haplotype confined to the Mashkid basin, whose origin can be traced back to a single introduction of a small number of propagules from Japan, and (2) a Chinese lineage represented by a single haplotype found in the Shafarood River of the Caspian Sea basin but also translocated to central Iran. This genetic clustering is somehow in correspondence to the dendrogram derived from the cluster analysis of geometric-morphometrics of P. parva populations and might be due to habitat-induced or genetically induced changes (e.g., fish origin), or it may arise due to the combination of both.

Assessing cervical spine and craniofacial morphology in Class II and Class III malocclusions: A geometric morphometric approach

ABSTRACT To compare craniofacial and cervical morphology between skeletal Classes II and III applying Geometric Morphometric Methods (GMM). Twenty-six cervical and craniofacial landmarks of 40 Class II and 39 Class III individuals were digitalized on lateral cephalograms. Procrustes ANOVA, generalized Procrustes, principal component analyses, and thin-plate spline function were applied to assess the pattern of shape variation of craniofacial structure and the cervical spine in relation to skeletal classes. Compared with Class III, Class II individuals presented a maxillary protrusion, mandibular retrusion, shorter mandibular corpus, posterior mandibular ramus rotation, anterior cranial base rotation, and a smaller centroid size. Furthermore, a forward and smaller cervical spine were observed. With GMM, the shape and size differences between skeletal classes can be analyzed visually and numerically.

Application of Shape Analyses to Recording Structures of Marine Organisms for Stock Discrimination and Taxonomic Purposes

Morphometric analysis of biogenic recording structures within marine organisms has applications in stock assessment, taxonomics, and ecomorphological studies, with shape variation markedly influenced by both genetics and the surrounding environment. Geometric morphometrics (GM) is an alternative approach to the “traditional” method of collecting linear measurements and applying multivariate statistical methods to these data. Landmark- and outline-based GM methods are suggested to have several advantages over the “traditional” method. Due to the increasing popularity of GM methods in the modern literature, this chapter first compares different morphometric techniques, and then reviews the methods applied to recording structures, with a focus on GM outline-based analyses. It is clear that outline methods have become a popular method of analysis for structures such as otoliths, particularly for the purpose of distinguishing between population components. However, for other structures such as beaks this technique is only in its early stages of application and is more difficult to apply but shows great promise for future studies. The advantages of using a holistic approach, incorporating several techniques including outline analysis for stock identification purposes is discussed.

The mandibles of the Honamli and Hair goat (Capra hircus); a geometric morphometric study

The aim of the study was to analyze mandible of the Honamli and Hair goats according to the sex factor by geometric morphometric methods. A total of 36 adult goat mandibles including 9 males and 9 females for each breed, were used in the study. After the mandibles were photographed from the left lateral side, 10 homolog landmarks were marked. Generalized Procrustes, Relative Warp, and Principal Component Analysis were performed for the data of landmark coordinates. In the study, the first principal component explained 28.752% and 37.325% of the total shape difference in the Honamli and Hair goat, respectively. In the analysis made among goat breeds according to the sex factor, the first principal component explained 40.809% of the total shape difference in females and 30.486% of the total shape difference in males. Consequently, the Hair goat showed a significant sex difference compared to the Honamli goat. Besides, it was remarkable that male goats clustered clearly compared to female goats in terms of the breed factor.

Leaf geometric morphometric analyses of Callicarpa and Geunsia (Lamiaceae) in the Malesian region

Abstract. Danila JS, Alejandro GJD. 2021. Leaf geometric morphometric analyses of Callicarpa and Geunsia (Lamiaceae) in the Malesian region. Biodiversitas 22: 4379-4390. Leaves are one of the most substantial organs of plants for it serves as a basis of species identification. Leaf morphology provides distinguishing features that help in the discrimination of plant species as well as investigation of leaf features among populations. This study aimed to investigate leaf shape variations between the two genera Geunsia Blume group and its closely related taxon, Callicarpa L. (Lamiaceae) using a landmark-based geometric morphometric method. The differences in the leaf shape among former members of Geunsia, namely C. apoensis, C. basilanensis, C. flavida, C. paloensis, C. pentandra, C. ramiflora, and C. surigaensis are also evaluated. Two primary landmarks and 14 semilandmarks were assigned in all samples to represent changes around the leaf margin. The Procrustes fit was generated using MorphoJ software which displays the mean and landmark position for individual configurations. Canonical Variate Analysis (CVA) and Mahalanobis Distance (MD) were able to discriminate all samples of Geunsia species using a scatter plot. Furthermore, Procrustes ANOVA showed a significant difference (P = 0.0082) among the seven species of the Geunsia group. Based on the results obtained, geometric morphometrics of leaf shape is effective in interspecific discrimination within members of Geunsia. However, the result of Discriminant Analysis (DA) showed that Geunsia and Callicarpa groups made leaf shape differences inefficient in discriminating the two genera. Therefore, further morphological studies on landmark-based geometric morphometrics of leaf shape involving a larger number of samples especially in the study of intergeneric classification are suggested.

Comparison of the fish functional arrangement of two contrasting localities in the Gulf of Mexico

AbstractA central objective of ecological research is to understand the causes and links of diversity. Trophic and morphological variation has been recognized as the baseline to determine communities’ functional arrangement; however, few morphological structures have been explored. In the present study, the fish assemblage of two contrasting localities within the Gulf of Mexico, the Campeche Bank (CB) and the Perdido Fold Belt (PFB), was examined to (1) analyse and compare the size, weight, trophic, and morphological (fish body and otolith) variation and (2) test if the otoliths morphological variation can be used to estimate the fish‐body variation. Fish and otolith size, fish and stomach–intestine weight, and stomach content were determined and geometric morphometric methods were applied to the fish body and otoliths. The fish body shows a relationship with the weight measurement and the otolith size, no differences in these variables were found between the two localities. In both localities Annelida, Mollusca, Osteichthyes, and Crustacean are the most common preys; however, the CB assemblage was more diverse in both diet and morphology and six trophic groups and 18 ecomorphological groups were determined, while in PFB, four trophic groups and 13 ecomorphological groups were determined. Finally, according to the morphological comparison in both localities, the otolith variation can be used to estimate the fish‐body morphological diversity. This study reports important information in the understanding of the links between morphological structures and highlights the importance of the otoliths as a morphological variable that reflects a wide range of ecomorphological variation of the fish body.

Two kinds of asymmetry in spring wheat leaf blade

The aim of the study was to find differences in the shape and asymmetry of the leaf blade of spring wheat grown at different dose of fertilizer. 52 landmarks were applied to the digitized images of the leaf blade and using the methods of geometric morphometrics the shape configuration was aligned. The components of the shape and asymmetry were estimated using Procrustes distances. Two types of asymmetry – fluctuating and directional were evaluated in Procrustes analysis of variance. The Procrustes distance showed a difference in the shape of the leaves of plants grown on mineral fertilizers in compare to the control (0.003; p <0.001). Visually, the width of the leaf blade of the plants formed with fertilization was bigger than in the control leaves. With an increase in the fertilizer dose, the Goodall criterion value increased from 30.0 to 46.2 (directional asymmetry; p <0.0001) and from 3.8 to 23.02 (fluctuating asymmetry; p <0.0001). There was no change in overall asymmetry of the experimental leaves, as Procrustean distance showed no difference between the centers of the sets in experimental variables (p ≥0.05). Thus, an increase in the dose of mineral-organic fertilizer influenced both the shape and the asymmetry including the structure of the bilateral asymmetry of spring wheat leaf blades, influencing the homeostasis of plant development.

The relationship between sternum variation and mode of locomotion in birds

BackgroundThe origin of powered avian flight was a locomotor innovation that expanded the ecological potential of maniraptoran dinosaurs, leading to remarkable variation in modern birds (Neornithes). The avian sternum is the anchor for the major flight muscles and, despite varying widely in morphology, has not been extensively studied from evolutionary or functional perspectives. We quantify sternal variation across a broad phylogenetic scope of birds using 3D geometric morphometrics methods. Using this comprehensive dataset, we apply phylogenetically informed regression approaches to test hypotheses of sternum size allometry and the correlation of sternal shape with both size and locomotory capabilities, including flightlessness and the highly varying flight and swimming styles of Neornithes.ResultsWe find evidence for isometry of sternal size relative to body mass and document significant allometry of sternal shape alongside important correlations with locomotory capability, reflecting the effects of both body shape and musculoskeletal variation. Among these, we show that a large sternum with a deep or cranially projected sternal keel is necessary for powered flight in modern birds, that deeper sternal keels are correlated with slower but stronger flight, robust caudal sternal borders are associated with faster flapping styles, and that narrower sterna are associated with running abilities. Correlations between shape and locomotion are significant but show weak explanatory power, indicating that although sternal shape is broadly associated with locomotory ecology, other unexplored factors are also important.ConclusionsThese results display the ecological importance of the avian sternum for flight and locomotion by providing a novel understanding of sternum form and function in Neornithes. Our study lays the groundwork for estimating the locomotory abilities of paravian dinosaurs, the ancestors to Neornithes, by highlighting the importance of this critical element for avian flight, and will be useful for future work on the origin of flight along the dinosaur-bird lineage.

Exploratory Analysis of Color Forms' Variability in the Invasive Asian Lady Beetle Harmonia axyridis (Pallas 1773).

Simple SummaryIn the following study, methods of geometric morphometrics were used to identify invasive forms of Harmonia axyridis. The study confirms the efficiency of geometric morphometrics as a tool for identifying minimal shape plasticity in wing shape and patterns of sexual shape dimorphism among invasive forms. Although more detailed studies are needed for further clarity, the study demonstrates that these methods can analyze phenotypic differences among the forms and reveal subtle phenotypic changes that explain genetic alterations within an invasive H. axyridis species.The Asian ladybird (Harmonia axyridis Pallas), native to Asia, is one of the 100 most invasive species in the world and has spread worldwide. This study aimed to characterize color forms of H. axyridis in Croatia and to analyze the variability of wing shape between populations and indicated forms. Geometric morphometric methods were used to analyze a total of 129 left and right wings in males and 126 left and right wings in females of H. axyridis collected from four different sites in Croatia. The results show a significant difference in wing shapes between the studied forms. Each form had its own specific morphotype that likely originated under the influence of genetic changes in the species. This study demonstrates that the use of geometric morphometric analysis is effective in studying the variability in H. axyridis populations. As this study is the first of its kind, for further clarity, it is necessary to conduct additional studies on a larger number of sites and an equal number of individuals of all forms.

Body shape variation of Garra rufa (Teleostei, Cyprinidae) populations in the Tigris basin in Iran using geometric morphometric analysis

Geometric morphometric method was used to examine the body shape variations among the six populations of Garra rufa , in Iranian part of Tigris basin. A total of 15 landmark-points was used for 170 specimens to hypothesize population differentiation of G. rufa in the six rivers and reservoir. In discriminant function analysis, 85.9% of original grouped cases correctly classified. Principal component analysis (PCA) and canonical variates analysis (CVA) confirmed the significant difference between the populations. The results revealed that the studied populations are divided into three clades based on differences in body depth, caudal peduncle length, backward moving of anal fin. Caudal peduncle showed shortening trend in five populations. Narrower body shape was dominated among specimens of four regions. Studies on body shape provide supporting data on fisheries, stock management, and conservative programs.

Development of novel artificial intelligence systems to predict facial morphology after orthognathic surgery and orthodontic treatment in Japanese patients

From a socio-psychological standpoint, improving the morphology of the facial soft-tissues is regarded as an important therapeutic goal in modern orthodontic treatment. Currently, many of the algorithms used in commercially available software programs that are said to provide the function of performing profile prediction are based on the false assumption that the amount of movement of hard-tissue and soft-tissue has a proportional relationship. The specification of the proportionality constant value depends on the operator, and there is little evidence to support the validity of the prediction result. Thus, the present study attempted to develop artificial intelligence (AI) systems that predict the three-dimensional (3-D) facial morphology after orthognathic surgery and orthodontic treatment based on the results of previous treatment. This was a retrospective study in a secondary adult care setting. A total of 137 patients who underwent orthognathic surgery (n = 72) and orthodontic treatment with four premolar extraction (n = 65) were enrolled. Lateral cephalograms and 3-D facial images were obtained before and after treatment. We have developed two AI systems to predict facial morphology after orthognathic surgery (System S) and orthodontic treatment (System E) using landmark-based geometric morphometric methods together with deep learning methods; where cephalometric changes during treatment and the coordinate values of the faces before treatment were employed as predictive variables. Eleven-fold cross-validation showed that the average system errors were 0.94 mm and 0.69 mm for systems S and E, respectively. The total success rates, when success was defined by a system error of < 1 mm, were 54% and 98% for systems S and E, respectively. The total success rates when success was defined by a system error of < 2 mm were both 100%. AI systems to predict facial morphology after treatment were therefore confirmed to be clinically acceptable.