Land of the giants: Body mass estimates of Palaeoloxodon from the Pleistocene of Taiwan

Abstract

The sea bottom of Taiwan Strait harbors a Late Pleistocene paleo-ecosystem significantly distinct from the present ecosystem structure in Taiwan. The assemblage constitutes fossil remains from the genus Palaeoloxodon, the largest known lineage of proboscideans to have walked on Earth. Body mass holds a pivotal role in our understanding of an organism's biology, ecology, life history, and susceptibility to extinction, and thus, is a key trait while working with extinct taxa. Here we, for the first time, assess the body mass of Palaeoloxodon specimens from Taiwan using well-established allometric scaling equations derived from both extant and extinct species. Our results indicate that Palaeoloxodon individuals from Taiwan exceed 10 tonnes in body mass with a mean body mass of 9.32 tonnes, similar in size to Palaeoloxodon antiquus across Eurasia, and an average shoulder height of 3.49 m. Additionally, our statistical pairwise analysis of body mass distribution shows that Palaeoloxodon specimens from Taiwan significantly differ from the largest species in the genus, Palaeoloxodon namadicus. We further employ equations from extant proboscideans and show notable discrepancies due to differences in body shape between extinct and extant proboscideans. Our estimated body masses offer novel insights into the paleoecology and extinction pressures of the Palaeoloxodon population during the Pleistocene of Taiwan. Further research promises to reveal the habitats capable of sustaining megafaunal populations and extinction events along the easternmost margin of Eurasia.