Discrimination of the species of the Crassiphycus corneus/C. usneoides complex (Gracilariaceae, Rhodophyta) through geometric morphometric analysis

Nova Hedwigia ◽  
2019 ◽  
Vol 109 (3) ◽  
pp. 291-301 ◽  
Author(s):  
Martha Isabel Vilchis ◽  
Jiri Neustupa ◽  
Kurt Dreckmann ◽  
Alejandra Quintanar ◽  
Abel Sentíes
Keyword(s):  
Principal Component Analysis ◽  
Morphometric Analysis ◽  
Principal Component ◽  
Fourier Descriptors ◽  
Cortical Cells ◽  
Geometric Morphometric ◽  
Phenotypic Differences ◽  
Geometric Morphometric Analysis ◽  
Elliptic Fourier Descriptors ◽  
Manova Analysis

The results of the discrimination by geometric morphometry of the species within the Crassiphycus corneus/C. usneoides complex is presented, from the shape of its cortical, subcortical and medullary cells in the apical, medium and basal portions of thallus. Principal component analysis, based on the elliptic Fourier descriptors of cellular outline shapes and NP-MANOVA analysis, show that only the cortical cells in the medium portion were significantly wider in C. corneus than in C. usneoides. The isoperimetric quotients (Q) indicated that these cells were significantly more circular in C. corneus than in C. usneoides. We conclude that the outline analyses efficiently recovered phenotypic differences between the species defined by molecular systematics and considered to be cryptic, so far.

scholarly journals Digital Morphometrics: A Tool for Leaf Morpho- Taxonomical Studies

2021 ◽  
Vol 1 (2) ◽  
pp. 1-7
Author(s):  
Kavi K. Oza ◽  
Rinku J. Desai ◽  
Vinay M. Raole*
Keyword(s):  
Principal Component Analysis ◽  
Abiotic Factors ◽  
Leaf Shape ◽  
Principal Component ◽  
Component Analysis ◽  
Herbarium Specimens ◽  
Fourier Descriptors ◽  
Shape Variation ◽  
Quantitative Analysis Method ◽  
Elliptic Fourier Descriptors

Leaves are most important part of the plant and can be used for the identification of a taxon. An appropriate understanding of leaf development in terms of shape and responsible abiotic factors is necessary for improvement in plant. Leaf shape variation could be evaluated successfully, and the symmetrical and asymmetrical elements of the overall shape variation could be detected. The aim of the present study was to establish a quantitative analysis method of leaf shape by elliptic Fourier descriptors and principal component analysis (EF-PCA). EF-PCA describes an overall shape mathematically by transforming coordinate information concerning its contours into elliptic Fourier descriptors (EFDs) and summarizing the EFDs by principal component analysis. We can be able to extract six variables by using leaf specimen images from field and herbarium specimens. In the present study, total leaf area with respect to notch area is more variable within species. Within a species the major source of the symmetrical elements may be governed by genotypic features and the asymmetrical elements are strongly affected by the environment. We could discuss the value of morphometrics to detect subtle morphological variation which may be undetectable by human eye.

scholarly journals Geometric morphometric analysis of intratrackway variability: A case study on theropod and ornithopod dinosaur trackways from Münchehagen (Lower Cretaceous, Germany)

2016 ◽  
Author(s):  
Jens N Lallensack ◽  
Anneke H van Heteren ◽  
Oliver Wings
Keyword(s):  
Morphometric Analysis ◽  
Lower Cretaceous ◽  
Principal Component ◽  
Lower Saxony ◽  
Geometric Morphometric ◽  
Variable Regions ◽  
Substrate Properties ◽  
Geometric Morphometric Analysis ◽  
Left And Right

A profound understanding of the influence of trackmaker anatomy, foot movements and substrate properties is crucial for any interpretation of fossil tracks. In this case study we analyze variability of footprint shape within one large theropod (T3), one medium-sized theropod (T2) and one ornithopod (I1) trackway from the Lower Cretaceous of Münchehagen (Lower Saxony, Germany) in order to determine the informativeness of individual features and measurements for ichnotaxonomy, trackmaker identification, and the discrimination between left and right footprints. Landmark analysis is employed based on interpretative outline drawings derived from photogrammetric data, allowing for the location of variability within the footprint and the assessment of covariation of separate footprint parts. Objective methods to define the margins of a footprint are tested and shown to be sufficiently accurate to reproduce the most important results. The lateral hypex and the heel are the most variable regions in the two theropod trackways. As indicated by principal component analysis, a posterior shift of the lateral hypex is correlated with an anterior shift of the margin of the heel. This pattern is less pronounced in the ornithopod trackway, indicating that variation patterns can differ in separate trackways. In all trackways, hypices vary independently from each other, rendering their relative position a questionable feature for ichnotaxonomic purposes. Most criteria commonly employed to differentiate between left and right footprints assigned to theropods are found to be reasonably reliable. The described ornithopod footprints are asymmetrical, again allowing for a left-right differentiation. Strikingly, 12 out of 19 measured footprints of the T2 trackway are stepped over the trackway midline, rendering the trackway pattern a misleading left-right criterion for this trackway. Traditional measurements were unable to differentiate between the theropod and the ornithopod trackways. Geometric morphometric analysis reveals potential for improvement of existing discriminant methods.

scholarly journals Geometric morphometric analysis of intratrackway variability: A case study on theropod and ornithopod dinosaur trackways from Münchehagen (Lower Cretaceous, Germany)

2016 ◽  
Author(s):  
Jens N Lallensack ◽  
Anneke H van Heteren ◽  
Oliver Wings
Keyword(s):  
Morphometric Analysis ◽  
Lower Cretaceous ◽  
Principal Component ◽  
Lower Saxony ◽  
Geometric Morphometric ◽  
Variable Regions ◽  
Substrate Properties ◽  
Geometric Morphometric Analysis ◽  
Left And Right

A profound understanding of the influence of trackmaker anatomy, foot movements and substrate properties is crucial for any interpretation of fossil tracks. In this case study we analyze variability of footprint shape within one large theropod (T3), one medium-sized theropod (T2) and one ornithopod (I1) trackway from the Lower Cretaceous of Münchehagen (Lower Saxony, Germany) in order to determine the informativeness of individual features and measurements for ichnotaxonomy, trackmaker identification, and the discrimination between left and right footprints. Landmark analysis is employed based on interpretative outline drawings derived from photogrammetric data, allowing for the location of variability within the footprint and the assessment of covariation of separate footprint parts. Objective methods to define the margins of a footprint are tested and shown to be sufficiently accurate to reproduce the most important results. The lateral hypex and the heel are the most variable regions in the two theropod trackways. As indicated by principal component analysis, a posterior shift of the lateral hypex is correlated with an anterior shift of the margin of the heel. This pattern is less pronounced in the ornithopod trackway, indicating that variation patterns can differ in separate trackways. In all trackways, hypices vary independently from each other, rendering their relative position a questionable feature for ichnotaxonomic purposes. Most criteria commonly employed to differentiate between left and right footprints assigned to theropods are found to be reasonably reliable. The described ornithopod footprints are asymmetrical, again allowing for a left-right differentiation. Strikingly, 12 out of 19 measured footprints of the T2 trackway are stepped over the trackway midline, rendering the trackway pattern a misleading left-right criterion for this trackway. Traditional measurements were unable to differentiate between the theropod and the ornithopod trackways. Geometric morphometric analysis reveals potential for improvement of existing discriminant methods.

Elliptic Fourier analysis and perceptual matching for the evaluation of bioinspired sketching in conceptual design

2017 ◽  
Vol 32 (1) ◽  
pp. 92-107
Author(s):  
Zhongliang Yang ◽  
Yumiao Chen ◽  
Zheng Liu
Keyword(s):  
Principal Component Analysis ◽  
Conceptual Design ◽  
Pearson Correlation ◽  
Principal Component ◽  
Component Analysis ◽  
Fourier Descriptors ◽  
Elliptic Fourier Analysis ◽  
Elliptic Fourier Descriptors ◽  
Matching Degree ◽  
Perceptual Matching

AbstractBiologically inspired design can be used to aid in conceptual design. Sketching is an important ideation process in conceptual design for recording and evaluating flashing moments of inspiration. The present study aims to provide a framework for exploring the effects of biological examples on the sketching contours of products, as well as the perceptual matching degree between design ideas generated via sketching and the desired functions. Elliptic Fourier descriptors with principal component analysis and perceptual matching were used to evaluate and compare the effects of biological examples, no examples, and human-engineered examples from different product categories and within one product category on the sketches in an experiment that involved 28 participants. The application of elliptic Fourier descriptors with principal component analysis shows that there are significant differences in the third and seventh principal components. It is also found that exposure to biological examples can produce more sketches with high perceptual matching degree than the other three conditions, but there are no significant effects of the example exposure on the Pearson correlation coefficients of semantic differential evaluation value vectors between design problems and sketches. These results demonstrate that exposure to biological examples will correlate with Elliptic Fourier descriptors of sketches and will not significantly increase the perceptual matching degree between sketches and the desired function.

scholarly journals Geometric morphometric analysis of intratrackway variability: a case study on theropod and ornithopod dinosaur trackways from Münchehagen (Lower Cretaceous, Germany)

PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e2059 ◽  
Author(s):  
Jens N. Lallensack ◽  
Anneke H. van Heteren ◽  
Oliver Wings
Keyword(s):  
Morphometric Analysis ◽  
Lower Cretaceous ◽  
Principal Component ◽  
Lower Saxony ◽  
Geometric Morphometric ◽  
Variable Regions ◽  
Substrate Properties ◽  
Geometric Morphometric Analysis ◽  
Left And Right

A profound understanding of the influence of trackmaker anatomy, foot movements and substrate properties is crucial for any interpretation of fossil tracks. In this case study we analyze variability of footprint shape within one large theropod (T3), one medium-sized theropod (T2) and one ornithopod (I1) trackway from the Lower Cretaceous of Münchehagen (Lower Saxony, Germany) in order to determine the informativeness of individual features and measurements for ichnotaxonomy, trackmaker identification, and the discrimination between left and right footprints. Landmark analysis is employed based on interpretative outline drawings derived from photogrammetric data, allowing for the location of variability within the footprint and the assessment of covariation of separate footprint parts. Objective methods to define the margins of a footprint are tested and shown to be sufficiently accurate to reproduce the most important results. The lateral hypex and the heel are the most variable regions in the two theropod trackways. As indicated by principal component analysis, a posterior shift of the lateral hypex is correlated with an anterior shift of the margin of the heel. This pattern is less pronounced in the ornithopod trackway, indicating that variation patterns can differ in separate trackways. In all trackways, hypices vary independently from each other, suggesting that their relative position a questionable feature for ichnotaxonomic purposes. Most criteria commonly employed to differentiate between left and right footprints assigned to theropods are found to be reasonably reliable. The described ornithopod footprints are asymmetrical, again allowing for a left–right differentiation. Strikingly, 12 out of 19 measured footprints of the T2 trackway are stepped over the trackway midline, rendering the trackway pattern a misleading left–right criterion for this trackway. Traditional measurements were unable to differentiate between the theropod and the ornithopod trackways. Geometric morphometric analysis reveals potential for improvement of existing discriminant methods.

scholarly journals Geometric morphometric analysis of spore shapes improves identification of fungi

PLoS ONE ◽  
2021 ◽  
Vol 16 (8) ◽  
pp. e0250477
Author(s):  
Alexander Ordynets ◽  
Sarah Keßler ◽  
Ewald Langer
Keyword(s):  
Species Identification ◽  
Morphometric Analysis ◽  
Fungal Spores ◽  
Principal Component ◽  
Test System ◽  
Linear Measurements ◽  
Geometric Information ◽  
Geometric Morphometric ◽  
Geometric Morphometric Analysis ◽  
Shape And Size

Morphology of organisms is an essential source of evidence for taxonomic decisions and understanding of ecology and evolutionary history. The geometric structure (i.e., numeric description of shape) provides richer and mathematically different information about an organism’s morphology than linear measurements. A little is known on how these two sources of morphological information (shape vs. size) contribute to the identification of organisms when implied simultaneously. This study hypothesized that combining geometric information on the outline with linear measurements results in better species identification than either evidence alone can provide. As a test system for our research, we used the microscopic spores of fungi from the genus Subulicystidium (Agaricomycetes, Basidiomycota). We analyzed 2D spore shape data via elliptic Fourier and principal component analyses. Using flexible discriminant analysis, we achieved the highest species identification success rate for a combination of shape and size descriptors (64.7%). The shape descriptors alone predicted species slightly better than size descriptors (61.5% vs. 59.1%). We conclude that adding geometric information on the outline to linear measurements improves the identification of the organisms. Despite the high relevance of spore traits for the taxonomy of fungi, they were previously rarely analyzed with the tools of geometric morphometrics. Therefore, we supplement our study with an open access protocol for digitizing and summarizing fungal spores’ shape and size information. We propagate a broader use of geometric morphometric analysis for microscopic propagules of fungi and other organisms.

scholarly journals A Geometric Morphometric Analysis of the Crown Form of the Maxillary Central Incisor in Humans

2018 ◽  
Vol 24 (1) ◽  
pp. 1-10
Author(s):  
Akiko Kato ◽  
Makiko Kouchi ◽  
Masaaki Mochimaru ◽  
Ayamoto Isomura ◽  
Norikazu Ohno
Keyword(s):  
Morphometric Analysis ◽  
Measurement Errors ◽  
Principal Component ◽  
T Test ◽  
Scaling Analysis ◽  
Micro Ct ◽  
Human Teeth ◽  
Geometric Morphometric ◽  
Significant Difference ◽  
Geometric Morphometric Analysis

Dental traits have been studied over a long period and grossly evaluated using standard reference plaques. However, grading by subjective observation may result in inter-observer measurement errors. We aimed to analyze crown models three-dimensionally to assess the morphology of the lingual surface termed shovel shape. Micro-CT scanned data of 38 maxillary central incisors stored at two different laboratories were used to create crown models of the outer enamel surface (OES) and the dentinoenamel junction (DEJ). Original crown data were evaluated according to the grade of shoveling into weak and strong groups. Homologous models consisting of the same number of data points were created and the distance matrices between tooth models of OES and DEJ were respectively analyzed by using multidimensional scaling analysis (MDS) and principal component analysis. Student’s t-test was used to compare corresponding scores between the two groups based on shovel-shape. The results of a t-test in the OES model indicated significant differences between the two groups. In contrast, the result in the DEJ model did not reveal a statistically significant difference. Our results indicate that geometric morphometric analysis of micro-CT scanned tooth crowns represents a powerful solution for the objective shape assessment of human teeth.

Description of a new Late Cretaceous species ofBulimulusLeach, 1814 (Orthalicoidea: Bulimulidae) using geometric morphometric analysis

2021 ◽  
Vol 87 (2) ◽  
Author(s):  
Fernanda Cabrera ◽  
Abraham S H Breure ◽  
Walter Norbis ◽  
Sergio Martínez
Keyword(s):  
Late Cretaceous ◽  
Morphometric Analysis ◽  
Principal Component ◽  
Canonical Variate ◽  
Geometric Morphometric ◽  
Fossil Species ◽  
Extant Species ◽  
Variate Analysis ◽  
Geometric Morphometric Analysis ◽  
A New Species

ABSTRACTIn the Late Cretaceous fossil record of Uruguay, three morphotypes of Bulimulus (Bulimulidae) have been recorded: Bulimulus klappenbachi and two undescribed ones. A geometric morphometric analysis was conducted to show whether the three morphotypes represent one or more species. With this aim, the three fossils were compared with three extant species of the same genus: Bulimulus bonariensis, B. guadalupensis and B. rushi. Variability within and among these three well-known extant species was tested to evaluate differences in the fossil morphotypes. Twenty-eight landmarks were selected (9 permanent landmarks and 19 semi-landmarks) and principal component analysis and canonical variate analysis were performed. Results indicate that only one of the unnamed morphotypes can be described as a new species and that the other is a variant of B. klappenbachi. The latter fossil species is described as Bulimulus frenguellii n. sp.

Sign in / Sign up

Export Citation Format

Share Document