Detecting dinosauromorphs among Triassic archosauriform trackways

[Ben Creisler <bcreisler@gmail.com>]

From: Ben Creisler
bcreisler@gmail.com


A new paper:

Tai Kubo and Mugino O. Kubo (2013)
Analysis of Triassic archosauriform trackways: difference in
stride/foot ratio between dinosauromorphs and other archosauriforms.
PALAIOS 28(4 ): 259-265
doi:10.2110/palo.2012.p12-099r
http://palaios.geoscienceworld.org/content/28/4/259.short?rss=1

Fossilized trackways have rarely been analyzed quantitatively to
examine major trends and patterns in evolution despite their potential
utility, especially in understanding locomotory evolution. In the
present study, trackways of Triassic archosauriforms were analyzed.
The analyses showed foot and stride lengths of archosauriforms
increased from the Early to Middle Triassic, especially those of
dinosauromorphs, which tripled. Dinosauromorphs were much smaller in
foot length and stride length compared to other archosauriforms during
the Early Triassic. They reached similar stride length compared with
other archosauriforms during the Middle Triassic and similar foot
length in the Late Triassic. Stride/foot ratio is significantly higher
in dinosauromorphs compared to other archosauriforms throughout the
Triassic. This relatively long stride length of dinosauromorphs is
attributed to either faster speed or higher relative hip height that
was probably caused by their digitigrade foot posture. Analyses of
trackway data sets, especially in combination with precise trackmaker
assignment and age determination, would bring us more thorough
knowledge about locomotory evolution of tetrapods that complements
body fossil evidence.