The pes ofAustralovenator wintonensis(Theropoda: Megaraptoridae): analysis of the pedal range of motion and biological restoration

Abstract

The pedal range of motion in Australovenator wintonensis is investigated to determine what influence soft tissue had on range of motion in the foot. Fortunately, the theropod pes shares a close morphology with extant large cursorial birds. Therefore, to better understand the pedal range of motion of Australovenator, the pedal range of motion of Dromaius novaehollandiae (commonly known as the emu) was analysed with and without soft tissue. We used a variety of innovative digital techniques to analyse the range of motion and biologically restore the Australovenator pes. Computed tomography scans of Dromaius pes in fully flexed and fully extended positions provided the soft tissue range of motion limits. The bone on bone range of motion of the same specimen was replicated following the removal of soft tissue. It was identified that there was an increase in range of motion potential with the removal of soft tissue. This variation provided a guide to develop the potential range of motion of a fully fleshed Australovenator pes. Additionally, the dissection of the Dromaius pes provided a guide enabling the replication of the corresponding soft tissue and keratin sheaths of the Australovenator pes.

3‐D range of motion envelopes reveal interacting degrees of freedom in avian hind limb joints

“…; White et al. , ). An accurate assessment of ROM about each of a joint's DoFs can test hypotheses of behavior by eliminating those that require poses or movements outside the range of accessibility (Senter, , ; Brougham & Brusatte, ; Pierce et al.…”

“…Paleontologists often seek to make inferences about function in extinct taxa known only from skeletal remains (e.g. Galton, 1971;Bramwell & Whitfield, 1974;Stevens & Parrish, 1999;Gishlick, 2001;Senter & Robins, 2005;Senter 2006;Carpenter & Wilson, 2008;Senter, 2009;Mallison, 2010a,b;Pierce et al 2012;Hutson & Hutson, 2014, 2015Nyakatura et al 2015;White et al 2015White et al , 2016. An accurate assessment of ROM about each of a joint's DoFs can test hypotheses of behavior by eliminating those that require poses or movements outside the range of accessibility (Senter, 2005(Senter, , 2009Brougham & Brusatte, 2010;Pierce et al 2012).…”

Investigating the stratigraphy and palaeoenvironments for a suite of newly discovered mid-Cretaceous vertebrate fossil-localities in the Winton Formation, Queensland, Australia

“…As described by Hocknull et al (2009) andPoropat et al, (2015a,b), site locations are geographically within 10's km and also situated stratigraphically in the very uppermost exposed Winton Formation. Structurally, the welldocumented Cork and Wetherby fault systems lie between several of these, with, LQCP and BNP lying to the east of the fault, and sites (AODL85) described by Poropat et al (2015a,b, and others) lying to the west (Salisbury et al, 2006a;Hocknull and Cook, 2008;Hocknull et al, 2009;White et al, 2012, Leahey & Salisbury, 2013White et al,2013;Poropat 2015a,b;White, 2016). Yet, detrital samples collected from key stratigraphic levels on both sides of the fault systems indicate little vertical offset, as both preserve a youngest…”

“…However, fossils do not exhibit abrasion or rounding, suggesting that they were entombed near-to the location of death. , 2006b;Hocknull and Cook, 2008;Hocknull et al, 2009;Agnolin et al, 2010;Molnar, 2010;White et al 2012White et al , 2013Leahey and Salisbury, 2013;Poropat 2014a,b;White et al, 2015;Cook et al, 2016;Poropat et al, 2016;White et al 2016). …”

A methodology of theropod print replication utilising the pedal reconstruction of Australovenator and a simulated paleo-sediment

“…The variance of ROM with and without soft tissue was applied to the ROM of the Australovenator pes which provided an estimation for the soft tissue ROM (White et al., 2016). …”