10.5061/DRYAD.PN12533
Lallensack, Jens N.
University of Bonn
Engler, Thomas
University of Bonn
Barthel, H. Jonas
University of Bonn
Data from: Shape variability in tridactyl dinosaur footprints: the
significance of size and function
Dryad
dataset
2019
Functional morphology
Ornithischia
Theropoda
dinosaur tracks
2019-11-19T00:00:00Z
2019-11-19T00:00:00Z
en
https://doi.org/10.1111/pala.12449
137536 bytes
2
CC0 1.0 Universal (CC0 1.0) Public Domain Dedication
The functional anatomy of the hindlimb of bipedal dinosaurs has been
intensively studied. Yet, surprisingly little work has been done
concerning functional adaptations in the digits for terrestrial
locomotion. While complete and articulated pes skeletons are scarce, pes
shape is abundantly recorded by fossil footprints. Here we aim to
elucidate the significance of footprint shape and size for locomotion
using a large sample (n = 303) of tridactyl dinosaur footprints from a
broad range of geographic localities and time slots. Size and shape
variation is characterised separately for theropods and ornithischians,
the two principal trackmaker taxa. At smaller sizes, theropod footprints
are best discriminated from ornithischian footprints based on their
smaller interdigital angle and larger projection of digit III, while at
larger sizes digital widths are effective discriminants. Ornithischian
footprints are shown to increase in size from the Early Jurassic to the
Late Cretaceous, a trend not observed in theropod footprints. Size and
function are argued to be important determinants of footprint shape, and
an attempt made to infer function from shape. Digit III projection and
length-to-width ratio of the footprints are negatively correlated with
size in both trackmaker groups, while digit impression widths are
positively correlated with size only in ornithischians. Digit III
projection is proposed to be positively correlated with cursorial ability.
Increased interdigital angles are associated with a decrease in digital
widths, possibly representing an adaptation for stability. Footprints are
found to yield great unrecognised potential for the understanding of the
functional morphology of dinosaur feet.
Table S1Spreadsheet containing collected data, with literature sources
indicated.Supplementary Material S1.csvTable S2Tables with correlation
coefficients and p-values for 1) the complete sample of tridactyl dinosaur
tracks, 2) theropod tracks, and 3) ornithischian tracks.Supplementary
Material S2.pdfSupplementary Material S3Variable loadings of the PCA of
the theropod subsample (Fig. 5A)Supplementary Material S4Variable loadings
of the PCA of the ornithischian subsample (Fig. 5B)Supplementary Material
S5Canonical coefficients of the CVA (Fig. 4A)