The smallest of the largest: new volumetric body mass estimate and in-vivo restoration of the dwarf elephant Palaeoloxodon ex gr. P. falconeri from Spinagallo Cave (Sicily)

ABSTRACT

In the present paper we provide a new estimate of the body mass (BM) of the dwarf elephant Palaeoloxodon ex gr. P. falconeri from Spinagallo cave (Sicily) at three different ontogenetic stages. The new estimates are based on 3D in-vivo restorations, digitally sculpted on anatomically updated photogrammetric models of the skeletons mounted at the Museo Universitario di Scienze della Terra (MUST), University of Rome (Italy). The new method provided an average BM of 249.98 kg for the adult male, 150.47 kg for the adult female, 38.81 kg for the juvenile male and 7.83 kg for the new-born male. Assuming as reliable these estimates, the values previously obtained by applying the regression formulae based on pad circumferences, shoulder height and long bone circumferences substantially would underestimate or overestimate the Spinagallo elephant BM up to 103%. The results obtained indicate that the volumetric methods can be regarded as the most solid and reliable to estimate the BM in those extinct vertebrates for which accurate mounted skeletons are available. This new method is therefore of critical importance for inferring the BM of taxa characterised by peculiar osteological proportions, such as those shown by the insular dwarf elephant analysed in the present work.

KEYWORDS:

• In-vivo restoration
• body mass estimate
• insular dwarfism
• Elephantidae
• pleistocene
• photogrammetry

Acknowledgments

The Editor-in-Chief Gareth J. Dyke and two anonymous reviewers are thanked for their suggestion and correction that greatly improved an early version of the manuscript. Linda Riti is warmly thanked for allowing us access to the specimens at the Museo Universitario di Scienze della Terra (MUST), University of Rome (Italy) and for her assistance in the collection. Part of this work was made possible by financial support from the DST/NRF Centre of Excellence for Palaeosciences (CoE in Palaeosciences), the NRF African Origins Platform and the Paleontological Society Sepkoski Grant 2018 to M.R.

Disclosure statement

No potential conflict of interest was reported by the authors.