
Explore the concept of morphometrics, contrasting traditional measurements with landmark-based geometric approaches, and apply 2d shape analysis to biological specimens using landmarks and coordinates.
Define biological two-dimensional landmarks on each specimen, ensuring identical point order and correspondence, using semi and geometric landmarks and tools like Mathematica and Morpheus, while addressing acquisition error and repeatability.
Explore two-dimensional morphometric analysis with landmarks visualization, detailing how landmark coordinates are aligned using Procrustes methods to reveal shape differences among taxa and visualize principal components.
Explore statistical analysis in practical morphometrics, including tests for differences in means between groups, discriminant and regression analysis, centroid size from landmarks, and permutation-based significance.
learn to acquire landmarks on 2d images with tpsDig, including preparing and naming images, importing them, and digitizing x and y coordinates to generate lmp landmark data.
Learn to acquire and digitize 2d morphometric landmarks with stereoMorph, including preparing images, labeling landmarks, exporting coordinates, and evaluating data formats and workflow challenges.
Explore landmark acquisition for two-dimensional morphometrics using the geomorph package, and practice digitizing 20 images with predefined landmark descriptions.
Assess digitizing error in 2d morphometrics by analyzing landmark coordinate variability from imaging, repeat measurements, and differences between operators and devices across specimens.
Explore GPA alignment and PCA analysis of 2D landmark morphometrics using Morpheus and Past to derive mean shapes and eigenvalues.
Explore the lollipop graph visualization for morphometrics, including threshold changes, TPS and wireframe representations, and comparing male and female specimens while addressing interpretation challenges.
Explore error assessment in procrustes anova by separating subject data, aligning 2d landmark configurations, and computing variance components to evaluate measurement error in morphometrics.
Learn landmark visualization in PAST 2.7 and 3.0, including importing data, configuring plots, and comparing groups for morphometric analysis.
Assess differences in mean morphometric measures between two groups, such as male and female, using ANOVA. Interpret the F value and the p value to determine group differences.
Compare ANOSIM and PERMANOVA as tests of group differences using distance measures like Euclidean; describe permutation-based p-values, power, and sample size effects on significance.
Explore regression analysis in 2D morphometrics by using central size as the predictor and shape coordinates as the response, evaluating transformations, plotting results, and comparing size effects across sexes.
Apply MANOVA to explore how size affects ship sites and maneuvers, interpreting lambda and p-values to assess significance and the impact of constraints on morphometric data.
This lecture demonstrates how to apply linear discriminant analysis to two-group morphometric data, interpret group separation, significance values, and classification results, and how choosing variables affects discriminatory power.
Measure euclidean distance between landmarks to quantify metric distances in a 2d morphometrics analysis; this lesson shows computing and presenting distances, with Python support.
Explore a practical walk-through of racial discrimination analysis using MR2 DB in 2D morphometrics, with 74 color images of European, African, and East Asian descent.
Morphometrics has experienced a major revolution through the invention of coordinate-based methods, the discovery of the statistical theory of shape, and the computational realization of deformation grids. The ubiquitous application of fast personal computers and modern analytical tools have ushered in a new era of data analysis, permitting the exploration and visualization of large high-dimensional data sets along with exact statistical tests based on resampling procedures. This new morphometric approach has been termed geometric morphometrics as it preserves the geometry of the landmark configurations throughout the analysis and thus permits to represent statistical results as actual shapes or forms. Therefore, these lectures aim at teaching practically, the concept of statistical shape analysis from 2D images. To encourage learning by exploration; images, annotations and data reports from the hand study are made available for download.