Giant ants and their shape: revealing relationships in the genusTitanomyrmawith geometric morphometrics

Shape is a natural phenomenon inherent to many different lifeforms. A modern technique to analyse shape is geometric morphometrics (GM), which offers a whole range of methods concerning the pure shape of an object. The results from these methods have provided new insights into biological problems and have become especially useful in the fields of entomology and palaeontology. Despite the conspicuous successes in other hymenopteran groups, GM analysis of wings and fossil wings of Formicidae has been neglected. Here we tested if landmarks defining the wing shape of fossil ants that belong to the genusTitanomyrmaare reliable and if this technique is able to expose relationships among different groups of the largest Hymenoptera that ever lived. This study comprises 402 wings from 362 ants that were analysed and assigned with the GM methods linear discriminant function analysis, principal component analysis, canonical variate analysis, and regression. The giant ant genusTitanomyrmaand the parataxonFormiciumhave different representatives that are all very similar but these modern methods were able to distinguish giant ant types even to the level of the sex. Thirty-five giant ant specimens from the Eckfeld Maar were significantly differentiable from a collection of Messel specimens that consisted of 187Titanomyrma giganteafemales and 42T. giganteamales, and from 74Titanomyrma simillimafemales and 21T. simillimamales. Out of the 324 Messel ants, 127 are newly assigned to a species and 223 giant ants are newly assigned to sex with GM analysis. All specimens from Messel fit to the two species. Moreover, shape affinities of these groups and the speciesFormicium brodiei,Formicium mirabile, andFormicium berryi, which are known only from wings, were investigated.T. giganteastands out with a possible female relative in one of the Eckfeld specimens whereas the other groups show similar shape patterns that are possibly plesiomorphic. Formicidae are one of the most dominant taxa in the animal kingdom and new methods can aid in investigating their diversity in the present and in deep time. GM of the ant wing delivers significant results and this core of methods is able to enhance the toolset we have now to analyse the complex biology of the ants. It can prove as especially useful in the future when incorporated into better understanding aspects of evolutionary patterns and ant palaeontology.

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Leaf geometric morphometrics among populations of Dalbergia ecastaphyllum (L.) Taub.

Bioscience Journal ◽

10.14393/bj-v35n6a2019-39814 ◽

2019 ◽

Vol 35 (6) ◽

Author(s):

Daniel Vieira de Morais ◽

Lorena Andrade Nunes ◽

Vandira Pereira da Mata ◽

Maria Angélica Pereira de Carvalho Costa ◽

Geni da Silva Sodré ◽

...

Keyword(s):

Principal Component Analysis ◽

Geometric Morphometrics ◽

Cross Validation ◽

Abiotic Factors ◽

Principal Component ◽

Canonical Variate ◽

Validation Test ◽

Significant Difference ◽

Variate Analysis ◽

Geographical Distances

Leaves are plant structures that express important traits of the environment where they live. Leaf description has allowed identification of plant species as well as investigation of abiotic factors effects on their development, such as gases, light, temperature, and herbivory. This study described populations of Dalbergia ecastaphyllum through leaf geometric morphometrics in Brazil. We evaluated 200 leaves from four populations. The principal component analysis (PCA) showed that the first four principal components were responsible for 97.81% of variation. The non-parametric multivariate analysis of variance (NPMANOVA) indicated significant difference between samples (p = 0.0001). The Mentel test showed no correlation between geographical distances and shape. The canonical variate analysis (CVA) indicated that the first two variables were responsible for 96.77 % of total variation, while the cross-validation test showed an average of 83.33%. D. ecastaphyllum leaves are elliptical and ovate.

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Sex Estimation Using Geometric Morphometrics

Forensic Anthropology ◽

10.5744/fa.2020.0019 ◽

2021 ◽

Author(s):

Valda Black

Keyword(s):

Geometric Morphometrics ◽

Classification Accuracy ◽

Function Analysis ◽

Dorsal Surface ◽

Two Dimensions ◽

Pubic Bone ◽

Biological Anthropology ◽

Sex Estimation ◽

Linear Discriminant ◽

Shape Changes

Creating and testing efficient techniques for the sex estimation of modern human skeletal remains has been a significant focus in biological anthropology. It is well established that the innominate, particularly the pubic bone, is a sexually dimorphic part of the human skeleton, but prone to fragmentation. Using modern pubic bones of known age and sex, this study aims to capture shape differences using geometric morphometrics (GMM) to test classification accuracy of segments of the pubic bone. The sample consists of 70 left adult pubic bones from the William M. Bass Donated Skeletal Collection, with 35 males and 35 females of mixed age and population affinity. Landmarks were placed on the dorsal surface of the pubic body and ischiopubic ramus to capture their overall shape in two dimensions, so the study is easily replicable and applicable. The scans were separately run through a generalized Procrustes, principal components (PCA), and canonical linear discriminant function analysis (DFA). The DFA results show high classification accuracy for the pubic body (94% males, 100% females) and the ischiopubic ramus (100% females, 97% males), with the PCA DFA allowing a researcher to explore specific shape changes driving the differentiation between groups. GMM was able to quantify and successfully discriminant the shape changes between males and females for small elements of the pubis, which can be applied to fragmentary remains and future morphological methods.

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Morphometric Analysis of Cranial Shape in Fossil and Recent Euprimates

Anatomy Research International ◽

10.1155/2012/478903 ◽

2012 ◽

Vol 2012 ◽

pp. 1-7 ◽

Cited By ~ 5

Author(s):

C. Verity Bennett ◽

Anjali Goswami

Keyword(s):

Function Analysis ◽

Cranial Morphology ◽

Evolutionary Patterns ◽

Linear Discriminant ◽

Landmark Data ◽

Components Analysis ◽

Fossil Primates ◽

Procrustes Superimposition ◽

Linear Discriminant Function Analysis ◽

3D Landmarks

Quantitative analysis of morphology allows for identification of subtle evolutionary patterns or convergences in anatomy that can aid ecological reconstructions of extinct taxa. This study explores diversity and convergence in cranial morphology across living and fossil primates using geometric morphometrics. 33 3D landmarks were gathered from 34 genera of euprimates (382 specimens), including the Eocene adapiforms Adapis and Leptadapis and Quaternary lemurs Archaeolemur, Palaeopropithecus, and Megaladapis. Landmark data was treated with Procrustes superimposition to remove all nonshape differences and then subjected to principal components analysis and linear discriminant function analysis. Haplorhines and strepsirrhines were well separated in morphospace along the major components of variation, largely reflecting differences in relative skull length and width and facial depth. Most adapiforms fell within or close to strepsirrhine space, while Quaternary lemurs deviated from extant strepsirrhines, either exploring new regions of morphospace or converging on haplorhines. Fossil taxa significantly increased the area of morphospace occupied by strepsirrhines. However, recent haplorhines showed significantly greater cranial disparity than strepsirrhines, even with the inclusion of the unusual Quaternary lemurs, demonstrating that differences in primate cranial disparity are likely real and not simply an artefact of recent megafaunal extinctions.

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Comparison of Wing, Ovipositor, and Cornus Morphologies between Sirex noctilio and Sirex nitobei Using Geometric Morphometrics

Insects ◽

10.3390/insects11020084 ◽

2020 ◽

Vol 11 (2) ◽

pp. 84

Author(s):

Ming Wang ◽

Lixiang Wang ◽

Ningning Fu ◽

Chenglong Gao ◽

Tegen Ao ◽

...

Keyword(s):

Geometric Morphometrics ◽

North Africa ◽

Principal Component ◽

Canonical Variate ◽

Native Range ◽

Sirex Noctilio ◽

Variate Analysis ◽

Global Presence ◽

And Cluster Analysis ◽

Taxonomic Studies

Sirex noctilio F. (Hymenoptera: Siricidae) is an invasive woodwasp from Europe and North Africa. Globalization has led to an expanding global presence in pine forests. S. noctilio has been previously introduced outside of its native range and now co-occurs in trees with native S. nitobei Matsumura (first discovered in 2016). Damage to Pinus sylvestris var. mongolica Litv in northeast China can be attributed to two types of woodwasp. To distinguish the two species by the traditional taxonomic morphology, we mainly differentiate the color of the male’s abdomen and the female’s leg. There remains intraspecific variation like leg color in the delimitation of related genera or sibling species of Sirex woodwasps. In this study, we used landmark-based geometric morphometrics including principal component analysis, canonical variate analysis, thin-plate splines, and cluster analysis to analyze and compare the wings, ovipositors, and cornus of two woodwasps to ascertain whether this approach is reliable for taxonomic studies of this group. The results showed significant differences in forewing venation and the shapes of pits in the middle of ovipositors among the two species, whereas little difference in hindwings and cornus was observed. This study assists in clarifying the taxonomic uncertainties of Siricidae and lays a foundation for further studies of the interspecific relationships of the genus Sirex.

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The application of pattern recognition techniques in metabolite fingerprinting of six differentPhyllanthusspp.

Spectroscopy An International Journal ◽

10.1155/2011/980109 ◽

2011 ◽

Vol 26 (1) ◽

pp. 69-78 ◽

Cited By ~ 3

Author(s):

Saravanan Dharmaraj ◽

Lay-Harn Gam ◽

Shaida Fariza Sulaiman ◽

Sharif Mahsufi Mansor ◽

Zhari Ismail

Keyword(s):

Pattern Recognition ◽

Principal Component ◽

Canonical Variate ◽

Batch Mode ◽

Mid Infrared ◽

Linear Discriminant ◽

Pattern Recognition Techniques ◽

Pattern Recognition Methods ◽

Ftir Spectrometer ◽

Component Models

FTIR spectroscopy was used together with multivariate analysis to distinguish six different species ofPhyllanthus. Among these speciesP. niruri,P. debilisandP. urinariaare morphologically similar whereasP. acidus,P. emblicaandP. myrtifoliusare different. The FTIR spectrometer was used to obtain the mid-infrared spectra of the dried powdered leaves in the region of 400–4000 cm−1. The region of 400–2000 cm−1was analyzed with four different pattern recognition methods. Initially, principal component analysis (PCA) was used to reduce the spectra to six principal components and these variables were used for linear discriminant analysis (LDA). The second technique used LDA on most discriminating wavenumber variables as searched by genetic algorithm using canonical variate approach for either 30 or 60 generations. SIMCA, which consisted of constructing an enclosure for each species using separate principal component models, was the third technique. Finally, multi-layer neural network with batch mode of backpropagation learning was used to classify the samples. The best results were obtained with GA of 60 gens. When LDA was run with the six wavenumbers chosen (1151, 1578, 1134, 609, 876 and 1227), 100% of the calibration spectra and 96.3% of the validation spectra were correctly assigned.

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Differentiation of Five Species of Megachile (Hymenoptera: Megachilidae), based on Wing Shape

Journal of Apicultural Science ◽

10.1515/jas-2016-0015 ◽

2016 ◽

Vol 60 (2) ◽

pp. 41-50 ◽

Cited By ~ 1

Author(s):

Shahram Falamarzi ◽

Behzad Habibpour ◽

Mohammad S. Mossadegh ◽

Alireza Monfared

Keyword(s):

Geometric Morphometrics ◽

Cross Validation ◽

Principal Component ◽

Wing Shape ◽

Canonical Variate ◽

Effective Technique ◽

Validation Test ◽

Variate Analysis ◽

Clear Differentiation ◽

Respective Species

Abstract In the present work we used landmark-based geometric morphometrics to compare the wing shapes of five species of Megachile (belonging to three subgenera) to confirm whether this technique may be used reliably for differentiation of this group. Analyses of wing shape by the use of principal component analysis (PCA), and canonical variate analysis (CVA) led to a clear differentiation among species. We found a close phenotypic similarity in wing shape between M. albisecta (belonging to the subgenus Creightonella) and M. picicornis (belonging to the subgenus Eutricharaea). According to the results of UPGMA, a higher degree of divergence between M. farinosa (belonging to the subgenus Pseudomegachile) and species belonging to other subgenera, was detected. The results of a cross-validation test indicated that geometric morphometrics is an effective technique to use for distinguishing between Megachile species. The reliability rate of this technique was between 85.71-100%. Using only two submarginal cell landmarks for generating shape variables, the cross-validation test correctly assigned individuals to their respective species, with a 92.85-100% reliability rate. Significant differences in wing size were obtained among the analysed species.

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Pattern of Morphological Variability in Unrepaired Unilateral Clefts With and Without Cleft Palate May Suggest Intrinsic Growth Deficiency

Frontiers in Cell and Developmental Biology ◽

10.3389/fcell.2020.587859 ◽

2020 ◽

Vol 8 ◽

Author(s):

Benny S. Latief ◽

Mette A. R. Kuijpers ◽

Adam Stebel ◽

Anne Marie Kuijpers-Jagtman ◽

Piotr S. Fudalej

Keyword(s):

Cleft Lip ◽

Cleft Lip And Palate ◽

Function Analysis ◽

Morphological Variability ◽

Vertical Direction ◽

Principal Component ◽

Canonical Variate ◽

Growth Deficiency ◽

Lateral Cephalograms ◽

Incisor Inclination

In individuals with cleft lip and palate (CLP) an iatrogenic effect of operations on subsequent maxillary growth is well-known. Much less is known about the association between occurrence of CLP and intrinsic growth deficiency of the maxillofacial complex. The aim of this study was to compare morphological variability in subjects with unilateral cleft lip and alveolus/palate and unaffected controls using geometric morphometric methods. The research hypothesis was that if subjects with unrepaired unilateral CLP have intrinsic growth deficiency, the pattern of their craniofacial growth variation may differ from that in unaffected individuals. Lateral cephalograms were available of three groups of the same ethnic background (Proto-Malayid): (a) non-syndromic unrepaired unilateral complete cleft lip, alveolus, and palate (UCLP), N = 66, mean age 24.5 years (b) non-syndromic unrepaired unilateral complete cleft lip and alveolus (UCLA), N = 177, mean age 23.7 years, and (c) NORM (N = 50), mean age 21.2 years without a cleft. Using geometric morphometrics shape variability in groups and shape differences between groups was analyzed. Principal component analysis (PCA) was used to examine shape variability, while differences between groups and sexes were evaluated with canonical variate analysis. Sexual dimorphism was evaluated with discriminant function analysis (DA). Results showed that in comparison to NORM subjects, shape variability in UCLA and UCLP is more pronounced in the antero-posterior than in vertical direction. Pairwise comparisons of the mean shape configurations (NORM vs. UCLA, NORM vs. UCLP, and UCLA vs. UCLP) revealed significant differences between cleft and non-cleft subjects. The first canonical variate (CV1, 68.2% of variance) demonstrated that differences were associated with maxillary shape and/or position and incisor inclination, while in females, the CV1 (69.2% of variance) showed a combination of differences of “maxillary shape and/or position and incisor inclination” and inclination of the cranial base. Shape variability demonstrated considerable differences in subjects with UCLA, UCLP, and NORM. Moreover, in subjects with a cleft, within-sample variability was more pronounced in the antero-posterior direction, while in non-cleft subjects, within-sample variability was more pronounced in the vertical direction. These findings may suggest that subjects with unilateral clefts have intrinsic growth impairment affecting subsequent facial development.

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Use of neural networks to diagnose acute myocardial infarction. I. Methodology

Clinical Chemistry ◽

10.1093/clinchem/42.4.604 ◽

1996 ◽

Vol 42 (4) ◽

pp. 604-612 ◽

Cited By ~ 7

Author(s):

J S Jørgensen ◽

J B Pedersen ◽

S M Pedersen

Keyword(s):

Myocardial Infarction ◽

Neural Networks ◽

Acute Myocardial Infarction ◽

Discriminant Function ◽

Discriminant Function Analysis ◽

Function Analysis ◽

Principal Component ◽

Clinical Problem ◽

Usual Practice ◽

Linear Discriminant

Abstract We investigated several aspects of using neural networks as a diagnostic tool: the design of an optimal network, the amount of patients' data needed to train the network, the question of training the network optimally while avoiding overfitting, and the influence of redundant variables. The specific clinical problem chosen for illustration was the diagnosis of acute myocardial infarction, given only the electrocardiogram and the concentration of potassium in serum at the time of admission. We found that, in contrast to usual practice, the termination of the training process should be based on the generalization performance and not on the training performance. We also found that a principal component analysis can be used to eliminate redundant variables, thereby reducing the data space. The diagnostic performance of the neural network we used was 78%--superior to that of linear discriminant function analysis but similar to that of quadratic discriminant function analysis.

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Detection of Morphometric Differentiation of Liza aurata (Pisces: Mugilidae) in Southeastern of the Caspian Sea, Iran

Our Nature ◽

10.3126/on.v11i2.9595 ◽

2014 ◽

Vol 11 (2) ◽

pp. 126-137 ◽

Cited By ~ 3

Author(s):

S. Kohestan-Eskandari ◽

H. AnvariFar ◽

H. Mousavi-Sabet

Keyword(s):

Caspian Sea ◽

Function Analysis ◽

Univariate Analysis ◽

Principal Component ◽

The Caspian Sea ◽

Morphometric Measurements ◽

Linear Discriminant ◽

Liza Aurata ◽

High Degree ◽

Management And Conservation

A 13-landmark morphometric truss network system was used for 135 specimens to investigate the hypothesis differentiation of golden grey mullet along the southeastern Caspian Sea. Univariate analysis of variance showed significant differences among the means of the three groups for 35 standardized morphometric measurements out of 78 characters studied. In linear discriminant function analysis (DFA), the overall assignment of individuals into their original groups was 66.7%. The proportions of individuals correctly classified into their original groups were 62.5%, 59.1%, 76.5% in Neka, Behshahr and Galogah populations, respectively. The Principal Component Analysis (PCA) showed that the specimens grouped into 2 areas with high degree of overlap. Clustering analysis based on Euclidean square distances among the studied groups of centroids using an UPGMA resulted segregation of the three populations into two distinct clusters. These results could be of interest for management and conservation programs of this species in the Caspian Sea.DOI: http://dx.doi.org/10.3126/on.v11i2.9595 Our Nature 2013, 11(2): 126-157

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Studying the Shape Variations of the Back, the Neck, and the Mandibular Angle of Horses Depending on Specific Feeding Postures Using Geometric Morphometrics

Animals ◽

10.3390/ani11030763 ◽

2021 ◽

Vol 11 (3) ◽

pp. 763

Author(s):

Federica Raspa ◽

Angela Roggero ◽

Claudia Palestrini ◽

Martina Marten Canavesio ◽

Domenico Bergero ◽

...

Keyword(s):

Geometric Morphometrics ◽

Management Practices ◽

Mixed Model ◽

Principal Component ◽

Canonical Variate ◽

Long Term Effects ◽

Mandibular Angle ◽

Variate Analysis ◽

The Right

The effects of specific feeding positions upon the horse’s shape variations of the back and neck postures as well as the variations of the mandibular angle have never been objectively studied. For this reason, geometric morphometrics was applied. Six horses, aged 14 ± 8 years (mean ± standard deviation, SD), were video-recorded while using three different feeding positions: on the ground—control position (CP); neck held 15 ± 3° below withers height with low hay net position (LP); neck held 15 ± 3° above withers height with high hay net position (HP). Data were analyzed using principal component analysis (PCA), multivariate analysis of variance (MANOVA), and partial least squares (PLS). A mixed model procedure was applied to evaluate differences in the magnitude of the mandibular angle. Whilst differences between individual horses were confirmed by canonical variate analysis (CVA), PCA analysis showed that a characteristic feeding position could also be identified on a group level. During the HP hay net position, the back and neck postures as well the mandibular angle were different compared to those exhibited by horses feeding from CP. In LP hay net position, the back posture more closely resembled those exhibited while feeding from CP; however, no similarity between LP and CP was found for neck posture and mandibular angle. Since only a few degrees of variation of the feeding position can influence back and neck postures, this aspect should be further investigated. The right compromise between horse welfare, horse safety, and management practices need to be further explored and long-term effects should be investigated.

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