No functional sexual dimorphism in Minorcan horse assessed by geometric morphometric methods

SummaryThe existence of sexual dimorphism in the Minorcan horse, an autochthonous breed from Minorca Island in the Balearic archipelago (NW Mediterranean Sea), is established in the official standard, with females being shorter and longer than males as well as having slenderer necks and a squarer croup. However, no study so far has explored the size and shape components of this dimorphism separately. The aim of this study was to analyse the morphology of this breed using geometric morphometric methods in order to find size and shape differences between sire lines. The analysis was based on landmarks digitized in lateral view from 38 registered adult Minorcan horses (20 males and 18 females) within an age range of 3–14 years (average 7 years) with different performance goals. The analyses did not reveal any significant differences between the “shape” and “size” of male and female animals, for the landmarks studied, so the sexes are functionally similar.

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Shape and size variations of Aegla uruguayana (Anomura, Aeglidae) under laboratory conditions: A geometric morphometric approach to the growth

Iheringia Série Zoologia ◽

10.1590/1678-4766201510517683 ◽

2015 ◽

Vol 105 (1) ◽

pp. 76-83 ◽

Cited By ~ 2

Author(s):

Valeria P. Diawol ◽

Federico Giri ◽

Pablo A. Collins

Keyword(s):

Life Cycle ◽

Sexual Dimorphism ◽

Geometric Morphometrics ◽

Individual Growth ◽

Freshwater Crab ◽

Dorsal Region ◽

Geometric Morphometric ◽

Life Cycle Stages ◽

Morphometric Methods ◽

Shape And Size

Crustacean growth studies typically use modal analysis rather than focusing on the growth of individuals. In the present work, we use geometric morphometrics to determine how organism shape and size varies during the life of the freshwater crab, Aegla uruguayana Schmitt, 1942. A total of 66 individuals from diverse life cycle stages were examined daily and each exuvia was recorded. Digital images of the dorsal region of the cephalothorax were obtained for each exuvia and were subsequently used to record landmark configurations. Moult increment and intermoult period were estimated for each crab. Differences in shape between crabs of different sizes (allometry) and sexes (sexual dimorphism; SD) were observed. Allometry was registered among specimens; however, SD was not statistically significant between crabs of a given size. The intermoult period increased as size increased, but the moult frequency was similar between the sexes. Regarding ontogeny, juveniles had short and blunt rostrum, robust forehead region, and narrow cephalothorax. Unlike juveniles crabs, adults presented a well-defined anterior and posterior cephalothorax region. The rostrum was long and stylised and the forehead narrow. Geometric morphometric methods were highly effective for the analysis of aeglid-individual- growth and avoided excessive handling of individuals through exuvia analysis.

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New Geometric Morphometric Insights in Digital Taphonomy: Analyses into the Sexual Dimorphism of Felids through Their Tooth Pits

Applied Sciences ◽

10.3390/app11177848 ◽

2021 ◽

Vol 11 (17) ◽

pp. 7848

Author(s):

Darío Herranz-Rodrigo ◽

Silvia J. Tardáguila-Giacomozzi ◽

Lloyd A. Courtenay ◽

Juan-José Rodríguez-Alba ◽

Antonio Garrucho ◽

...

Keyword(s):

Sexual Dimorphism ◽

Geometric Morphometrics ◽

Applied Statistics ◽

Panthera Tigris ◽

Panthera Pardus ◽

Geometric Morphometric ◽

Male And Female ◽

New Horizons ◽

Carnivore Species ◽

Felid Species

Recent studies using geometric morphometrics for taphonomy have yielded interesting results, opening new horizons of research in both archaeological and paleontological sites. Here we present the analysis of tooth pits left by male and female individuals of two different carnivore species (Panthera tigris and Panthera pardus) in order to see if sexual dimorphism influences the morphology of tooth pit marks. In the process, 3D-scanning and applied statistics were used. Based on samples derived from two individuals of different sexes, the present results indicate sexual dimorphism in these felid species to not be a conditioning factor of tooth pit morphology.

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Nasal index among Students of People’s Dental College and Hospital

Europasian Journal of Medical Sciences ◽

10.46405/ejms.v1i1.11 ◽

2019 ◽

Vol 1 (1) ◽

pp. 21-27

Author(s):

Mangesh Bajracharya ◽

Samjhana Sharma

Keyword(s):

Ethnic Identity ◽

Sexual Dimorphism ◽

Female Students ◽

Baseline Data ◽

Craniofacial Surgery ◽

Male And Female ◽

Size And Shape ◽

Gender Differentiation ◽

Significant Difference ◽

The Mean

Introduction: Nasal anthropometry is a study that deals with the measurements of the proportion, size, and shape of the nose. The nasal index is considered as one of the major landmarks for craniofacial surgery, gender differentiation, and ethnic identity. This study is aimed to provide baseline data of the nasal index of Nepalese people and to assess the gender variation which will be of clinical, surgical interest in rhinology and craniofacial prosthetic purpose. Methods: BDS students from 17 to 25 years with various ethnicity were included in the study. A total of 160 students with an equal number of male and female students was included. Nasal parameters were measured and the nasal index was calculated for each student. Result: The mean nasal index was 78.03±7.07 suggesting Mesorrhine type of nose. The nasal width and height show statistically significant differences whereas there was no significant difference found between the nasal indices of male and female students. Hill Janajati showed the highest nasal index followed by Newar, Brahmin and Chettri; and Others. Conclusion: The study concludes the type of nose has an effect on gender when compared between the sex but the nasal index calculated to have a little contribution to sexual dimorphism. Mesorrhine nose was found to be most frequent. Among the population, Hill Janajati showed the highest nasal index. We recommend further study to compare the nasal index of various ethnical groups of the Nepalese population. Keywords: Anthropometry, Mesorrhine, Nasal Index

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Sexual Dimorphism in Maxillary First Molar among Nepalese Population of Eastern Nepal

Birat Journal of Health Sciences ◽

10.3126/bjhs.v6i2.40331 ◽

2021 ◽

Vol 6 (2) ◽

pp. 1492-1495

Author(s):

Sanjib Kumar Sah ◽

Suman Pokhrel ◽

Umesh Kumar Mehata ◽

Raju Kumar Chaudhary ◽

Rajesh Kumar Shah

Keyword(s):

Sexual Dimorphism ◽

P Value ◽

Eastern Region ◽

Tooth Crown ◽

Male And Female ◽

Full Size ◽

Dental Examination ◽

Best Parameter ◽

Maxillary Arch ◽

Shape And Size

Introduction: Sexual dimorphism refers to differences in size, stature and appearance between male and female. It is a known fact that tooth crown is formed to full size in childhood even before eruption into oral cavity. The shape and size of the teeth permits an interesting dimension of study for sexual dimorphism, we aimed to delineate the sexual dimorphism by measuring the mesiodistal (MD) and buccolingual (BL) diameters of permanent maxillary first molar in Nepalese population of Eastern Nepal. Objectives: The aim of this study was to evaluate the sexual dimorphism in maxillary first molar among Nepalese population of eastern Nepal Methodology: 100 participants of either sex (50 males & 50 females) aged between 17 to 25 years were enrolled in the study. After thorough dental examination, impression of the maxillary arch was made and MD diameter and BL diameters were measured with the help of vernier caliper. A P value of <0.05 was considered as statistically significant. Results: Sexual dimorphism was found in MD and BL diameters of maxillary first molar in males measuring higher than females. Right mesiodistal showed the highest sexual dimorphism, whereas right buccolingual showed the least. Conclusions: This study confirms that permanent maxillary first molar shows significant sexual dimorphism, out of which mesiodistal measurement stands out to be the best parameter in Nepalese population of Eastern region.

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Two new genera of long clawed Isohypsibioidea Guil, Jørgensen & Kristensen, 2019

Zootaxa ◽

10.11646/zootaxa.4729.2.10 ◽

2020 ◽

Vol 4729 (2) ◽

pp. 293-299 ◽

Cited By ~ 1

Author(s):

ŁUKASZ KACZMAREK ◽

TOMASZ BARTYLAK ◽

MILENA ROSZKOWSKA

Keyword(s):

Genetic Data ◽

Lateral View ◽

New Genera ◽

Size And Shape ◽

Pharyngeal Apparatus ◽

Shape And Size

Two new eutardigrade genera Vladimirobius gen. nov. and Weglarskobius gen. nov. are erected for the species Grevenius irregibilis (Biserov, 1992) and Isohypsibius altai Kaczmarek & Michalczyk, 2006a, respectively. They are characterized by strongly modified claws, bucco-pharyngeal apparatus of the Isohypsibius variant, pharyngeal apophyses, and placoids present. The primary branches of internal claws of Vladimirobius gen. nov. are wide in lateral view and have very prominent gibbosity-like projections, whereas primary branches of external claws are thin and extremely long. In Weglarskobius gen. nov. claws IV are similar in shape and size, but the primary branches are extremely long, and thin. Moreover, claws on legs I–III vary greatly in size and shape in Weglarskobius gen. nov. Such supposed autapomorphies fully justify erection of the two new genera, even if the genetic data are presently unavailable.

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A Comparison of Traditional and Geometric Morphometric Techniques for the Study of Basicranial Morphology in Horses: A Case Study of the Araucanian Horse from Colombia

Animals ◽

10.3390/ani10010118 ◽

2020 ◽

Vol 10 (1) ◽

pp. 118

Author(s):

Pere Miquel Parés-Casanova ◽

Arcesio Salamanca-Carreño ◽

René Alejandro Crosby-Granados ◽

Jannet Bentez-Molano

Keyword(s):

Geometric Morphometrics ◽

Domestic Animal ◽

New Techniques ◽

Geometric Morphometric ◽

Animal Populations ◽

Morphometric Methods ◽

Mature Group ◽

Geometric Morphometric Analysis ◽

Shape And Size

Skull size and shape have been widely used to study domestic animal populations and breeds. Although several techniques have been proposed to quantify cranial form, few attempts have been made to compare the results obtained by different techniques. While linear morphometrics has traditionally been used in breed characterization, recent advances in geometric morphometrics have created new techniques for specifically quantifying shape and size. The objective of this study was to compare two morphometric methods for their ability to describe external morphology. For this purpose, 20 skull specimens of adult male Araucanian horses were examined. Two age categories were established (the “mature group”, M3 not fully erupted to moderately worn, n = 7; and the “senile group”, M3 totally erupted and highly worn, n = 13). Both methods showed that there were statistical differences between generations, but discrimination rates were different between methods with the geometric morphometric analysis obtaining a rate of 97.5%. Although linear morphometrics was found to be compatible with geometric morphometrics, the latter was better able to discriminate the two groups and it also provides more information on shape.

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Geometric morphometrics for the study of hemicoxae sexual dimorphism in a local domestic equine breed

Journal of Morphological Sciences ◽

10.4322/jms.063513 ◽

2014 ◽

Vol 31 (04) ◽

pp. 214-218 ◽

Cited By ~ 1

Author(s):

P. Parés-Casanova

Keyword(s):

Sexual Dimorphism ◽

Morphometric Analysis ◽

Reliable Method ◽

Sex Differentiation ◽

Horse Breed ◽

Geometric Morphometric ◽

Photographic Images ◽

Average Accuracy ◽

Pelvic Shape ◽

Shape And Size

Abstract Introduction and material and methods. Twenty-height skeletonised hemicoxae from young animals (yearlings, 13 males and 15 females) belonging to the “CavallPirinencCatalà” horse (Catalan Pyrenean Horse) breed were studied by means of geometric morphometric (GM) methods. Morphometric analysis was based on coordinates of 16 landmarks of the ilium and ischiopubic regions that were digitised on 2D photographic images. Sexes did not appear separated either by size or shape, the latter being independent of the former.K-means clustering of shape variables were used in order to classify individuals by sex and an average accuracy of 57.1% was achieved. Results. Males were misclassified more frequently than females. For the iliac landmarks, which contributed to the total variance of shape with the higher degree, the value obtained increased to 60.7% for k-means. The ischiopubic complex contributed less to sex differentiation according to shape. Conclusion. It is concluded that the use of GM and multivariate statistics is not a reliable method to quantify pelvic shape and size differences between the sexes for equine yearlings. This is the irst known study to apply GM to the hip of an equine breed.

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Size and shape analysis of two close Cyprinidae species (Garra variabilis-Garra rufa) by geometric morphometric methods

Survey in Fisheries Sciences ◽

10.18331/sfs2016.2.2.3 ◽

2016 ◽

Vol 2 (2) ◽

pp. 35-44 ◽

Cited By ~ 2

Author(s):

T. Cicek ◽

A. Kaya ◽

S. Bilici ◽

E. Ünlu

Keyword(s):

Shape Analysis ◽

Geometric Morphometric ◽

Size And Shape ◽

Garra Rufa ◽

Morphometric Methods

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Mobility in Ancient Egypt from the shape and strength of the femurs

Anthropological Review ◽

10.2478/anre-2021-0014 ◽

2021 ◽

Vol 84 (2) ◽

pp. 181-199

Author(s):

Herrerín Jesús ◽

Carmenate Margarita

Keyword(s):

Physical Activity ◽

Sexual Dimorphism ◽

Body Mass ◽

Ancient Egypt ◽

Daily Activities ◽

Sex Distribution ◽

Size And Shape ◽

Daily Occupation ◽

Intense Physical Activity ◽

Shape And Size

Abstract The aim of the study was to establish the degree of robustness and to infer the level of mobility of a group from ancient Thebes (Middle Egypt). Seventy-one left femurs of adult individuals from the 1st century AD from the tomb of Monthemhat (Luxor) were studied. Metrical, non-metrical variables, shape and size indices of femur were considered. Stature, body mass and Body Mass Index were calculated. All variables showed higher values in males, the vertical diameter of the femoral head was the variable with the highest sexual dimorphism. Non-metric variables also indicated low robustness, with heterogeneous sex distribution. The robustness, pilastric and platymeric indices indicated that the values were close to those of gracile populations in both sexes. Subtrochanteric size and shape showed no sexual dimorphism. The robustness, size and shape in the middle of the diaphysis suggested a mobility related to a daily occupation without intense physical activity in the legs. The results indicate a profile of low robustness, relative sedentarism with apparent sexual division in daily activities.

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