Morfometria y diferenciación craneal. Un caso en ovis
Skull morphometry and diferentation: a case in ovis
MetadataShow full item record
Techniques of traditional morphometry, based on the application of multivariate statistical methods on a set of linear variables, have been running since the appearance of personal computers. However, a variety of new techniques has emerged recently, grouped together in what has been called geometric morphometrics (GM) appropriate for the statistical study of variation and covariation of the form (shape + size). This is more useful and consistent for the study of the morphological variation than the traditional morphometry. For this GM study in domestic sheep, 39 skulls of adult animals (with at least the first two upper molars erupted) from 3 different areas of the pre-Pyrenees and Pyrenees were studied. Using digital pictures, 21 2D landmarks were recorded on their skull dorsal aspect. These individual coordinates were then adjusted by means of superimposing procrustes using the criterion of least squares or (Generalized Procrustes Analysis) generalized procrustes analysis. The analysis of the major components, using the variance-covariance matrix, detected 23 loading values > [0.1] from which we proceeded to the comparative study of the three populations resampling by using subsets of available data (jackknifing). The comparative study suggests that working with the size adds no more qualifying power for the differentiation of the sheep groups.