scholarly journals Scyland3D: Processing 3D landmarks

2020 ◽  
Vol 5 (46) ◽  
pp. 1262
Author(s):  
Fidji Berio ◽  
Yann Bayle
Keyword(s):  
3D Landmarks

Visual SLAM Based on Rigid-Body 3D Landmarks

2011 ◽  
Vol 66 (1-2) ◽  
pp. 125-149 ◽  
Author(s):  
Patricio Loncomilla ◽  
Javier Ruiz del Solar
Keyword(s):  
Rigid Body ◽  
Visual Slam ◽  
3D Landmarks

scholarly journals Morphometric Analysis of Cranial Shape in Fossil and Recent Euprimates

2012 ◽  
Vol 2012 ◽  
pp. 1-7 ◽  
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.

scholarly journals Evolution of the Unique Anuran Pelvic and Hind limb Skeleton in Relation to Microhabitat, Locomotor Mode, and Jump Performance

2020 ◽  
Vol 60 (5) ◽  
pp. 1330-1345 ◽  
Author(s):  
Shannon M Buttimer ◽  
Natasha Stepanova ◽  
Molly C Womack
Keyword(s):  
Hind Limb ◽  
Evolutionary Rate ◽  
Morphological Changes ◽  
Body Plan ◽  
Individual Species ◽  
Museum Collections ◽  
Jump Performance ◽  
Anuran Species ◽  
The Relationship ◽  
3D Landmarks

Abstract Anurans (frogs and toads) have a unique pelvic and hind limb skeleton among tetrapods. Although their distinct body plan is primarily associated with saltation, anuran species vary in their primary locomotor mode (e.g., walkers, hoppers, jumpers, and swimmers) and are found in a wide array of microhabitats (e.g., burrowing, terrestrial, arboreal, and aquatic) with varying functional demands. Given their largely conserved body plan, morphological adaptation to these diverse niches likely results from more fine-scale morphological change. Our study determines how shape differences in Anura’s unique pelvic and hind limb skeletal structures vary with microhabitat, locomotor mode, and jumping ability. Using microCT scans of preserved specimens from museum collections, we added 3D landmarks to the pelvic and hind limb skeleton of 230 anuran species. In addition, we compiled microhabitat and locomotor data from the literature for these species that span 52 of the 55 families of frogs and ∼210 million years of anuran evolution. Using this robust dataset, we examine the relationship between pelvic and hind limb morphology and phylogenetic history, allometry, microhabitat, and locomotor mode. We find pelvic and hind limb changes associated with shifts in microhabitat (“ecomorphs”) and locomotor mode (“locomorphs”) and directly relate those morphological changes to the jumping ability of individual species. We also reveal how individual bones vary in evolutionary rate and their association with phylogeny, body size, microhabitat, and locomotor mode. Our findings uncover previously undocumented morphological variation related to anuran ecological and locomotor diversification and link that variation to differences in jumping ability among species.

scholarly journals Reproducibility of three-dimensional landmarking and Frankfort horizontal plane construction: a comparison of conventional and novel landmarks in presurgical computed tomography scans

2021 ◽  
Author(s):  
Gauthier Dot ◽  
Frederic Rafflenbeul ◽  
Adeline Kerbrat ◽  
Philippe Rouch ◽  
Laurent Gajny ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Ct Scan ◽  
Three Dimensional ◽  
Computed Tomography Scans ◽  
Repeatability And Reproducibility ◽  
Frankfort Horizontal Plane ◽  
Cephalometric Measurements ◽  
Iso 5725 ◽  
Overall Reliability ◽  
3D Landmarks

Objectives To assess manual landmarking repeatability and reproducibility (R&R) of a set of three-dimensional (3D) landmarks and to evaluate R&R of vertical cephalometric measurements using two Frankfort Horizontal (FH) planes as references for horizontal 3D imaging reorientation. Methods Thirty-three landmarks, divided into "conventional", "foraminal" and "dental", were manually located twice by 3 experienced operators on 20 computed tomography (CT) scans of orthognathic surgery patients. R&R of the landmark localization were computed according to the ISO 5725 standard. These landmarks were then used to construct 2 FH planes: a conventional FH plane (orbitale left, porion right and left) and a newly proposed FH plane (midinternal acoustic foramen, orbitale right and left). R&R of vertical cephalometric measurements were computed using these 2 FH planes as horizontal references for CT reorientation. Results Landmarks showing a 95% confidence interval (CI) of repeatability and/or reproducibility > 2mm were found exclusively in the "conventional" landmarks group. Vertical measurements showed excellent R&R (95% CI < 1mm) with either FH plane as horizontal reference. However, the 2 FH planes were not found to be parallel (absolute angular difference of 2.41°, SD 1.27°). The average time needed to landmark one CT scan was 14 ± 3 minutes. Conclusions The "dental" and "foraminal" landmarks tended to be more reliable than the "conventional" landmarks. Despite the poor overall reliability of the landmarks orbitale and porion, the construction of the conventional FH plane using 3 landmarks provided a reliable horizontal reference for 3D craniofacial CT scan reorientation.

scholarly journals Big Choanae, Larger Face: Scaling Patterns Between Cranial Airways in Modern Humans and African Apes and Their Significance in Middle and Late Pleistocene Hominin Facial Evolution

2019 ◽  
Vol 31 (1-2) ◽  
pp. 5-13 ◽  
Author(s):  
M. Bastir
Keyword(s):  
Energy Demand ◽  
Regression Models ◽  
High Energy ◽  
Middle Pleistocene ◽  
Facial Skeleton ◽  
Large Airways ◽  
Middle And Late Pleistocene ◽  
Shed Light ◽  
3D Landmarks ◽  
Large Face

This study aimed to understand the ontogenetic and allometric relationships in scaling between the anterior and posterior openings of the cranial airways and facial size, in order to shed light on the mechanisms that might underlie the evolution of a large face and large airways in Middle Pleistocene hominins and Neandertals. Sizes were calculated from 3D landmarks measured on the facial skeleton and airway structures of 403 skulls from two ontogenetic series of H. sapiens and P. troglodytes, an adult sample of gorillas and 11 Middle Pleistocene hominins and Neandertals. RMA regression models were used to compare the patterns in scaling between the anterior and posterior airways in relation to overall facial size. Our results show that the size of the anterior airways correlates more positively with facial size than the size of the posterior airways. This ontogenetic mechanism could explain the large faces and noses in the Neandertal lineage despite the adverse effects of such a phenotype for respiratory air-conditioning in cold climates. A large facial size could be a developmentally constrained consequence of generating airways large enough to provide the necessary oxygen for high energy demand in this large-brained and heavy-bodied hominin lineage.

scholarly journals 3D revelation of phenotypic variation, evolutionary allometry, and ancestral states of corolla shape: a case study of clade Corytholoma (subtribe Ligeriinae, family Gesneriaceae)

GigaScience ◽  
2020 ◽  
Vol 9 (1) ◽  
Author(s):  
Hao-Chun Hsu ◽  
Wen-Chieh Chou ◽  
Yan-Fu Kuo
Keyword(s):  
Morphological Traits ◽  
Spatial Information ◽  
Shape Variation ◽  
Micro Computed Tomography ◽  
3D Images ◽  
X Ray ◽  
Evolutionary Allometry ◽  
Ancestral States ◽  
3D Landmarks

Abstract Background Quantification of corolla shape variations helps biologists to investigate plant diversity and evolution. 3D images capture the genuine structure and provide comprehensive spatial information. Results This study applied X-ray micro-computed tomography (µCT) to acquire 3D structures of the corollas of clade Corytholoma and extracted a set of 415 3D landmarks from each specimen. By applying the geometric morphometrics (GM) to the landmarks, the first 4 principal components (PCs) in the 3D shape and 3D form analyses, respectively, accounted for 87.86% and 96.34% of the total variance. The centroid sizes of the corollas only accounted for 5.46% of the corolla shape variation, suggesting that the evolutionary allometry was weak. The 4 morphological traits corresponding to the 4 shape PCs were defined as tube curvature, lobe area, tube dilation, and lobe recurvation. Tube curvature and tube dilation were strongly associated with the pollination type and contained phylogenetic signals in clade Corytholoma. The landmarks were further used to reconstruct corolla shapes at the ancestral states. Conclusions With the integration of µCT imaging into GM, the proposed approach boosted the precision in quantifying corolla traits and improved the understanding of the morphological traits corresponding to the pollination type, impact of size on shape variation, and evolution of corolla shape in clade Corytholoma.

scholarly journals TINA manual landmarking tool: software for the precise digitization of 3D landmarks

2012 ◽  
Vol 9 (1) ◽  
pp. 6 ◽  
Author(s):  
Anja C Schunke ◽  
Paul A Bromiley ◽  
Diethard Tautz ◽  
Neil A Thacker
Keyword(s):  
3D Landmarks
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