10.5061/DRYAD.X3FFBG7N2
Wimberly, Alexa
0000-0002-2601-6540
University of Chicago
Natale, Rossy
University of Chicago
Higgins, Robert
University College London
Slater, Graham
University of Chicago
Choice of 3D morphometric method leads to diverging interpretations of
form-function relationships in the carnivoran calcaneus
Dryad
dataset
2022
locomotion
ecomorphology
mammal
macro-evolution
FOS: Biological sciences
en
28479 bytes
2
CC0 1.0 Universal (CC0 1.0) Public Domain Dedication
Three dimensional morphometric methods are a powerful tool for comparative
analysis of shape. However, morphological shape is often represented using
landmarks selected by the user to describe features of perceived
importance, and this may lead to over confident prediction of
form-function relationships in subsequent analyses. We used Generalized
Procrustes Analysis (GPA) of 13 homologous 3D landmarks and spherical
harmonics (SPHARM) analysis, a homology-free method that describes the
entire shape of a closed surface, to quantify the shape of the calcaneus,
a landmark poor structure that is important in hind-limb mechanics, for
111 carnivoran species spanning 12 of 13 terrestrial families. Both
approaches document qualitatively similar patterns of shape variation,
including a dominant continuum from short/stout to long/narrow calcanea.
However, while phylogenetic generalized linear models indicate that
locomotor mode best explains shape from the GPA, the same analyses find
that shape described by SPHARM is best predicted by foot posture and body
mass without a role for locomotor mode, though effect sizes for all are
small. User choices regarding morphometric methods can dramatically impact
macroevolutionary interpretations of shape change in a single structure,
an outcome that is likely exacerbated when readily landmarkable features
are few.
A ReadMe file has been attached to guide the reader through our datasets
and code.