A new rhinoceros clade from the Pleistocene of Asia sheds light on mammal dispersals to the Philippines

Abstract

Rhinoceroses are among the most endangered mammalian species today. Their past diversity is well documented from the Eocene onward, although their evolutionary history is far from being fully understood. Here, we elucidate the systematic affinities of a Pleistocene rhinoceros species represented by a partial skeleton from 709 ± 68 kya archaeological deposits in Luzon Island, Philippines. We perform a comprehensive phylogenetic analysis, including all living species and a wide array of extinct rhinocerotid species. We confirm the early split between Elasmotheriinae and Rhinocerotinae at c. 35.5 Mya and constrain the divergence between recent Asian and African rhinoceroses at c. 24 Mya, with contrasting phenotypic evolutionary rates in Diceroti and Rhinoceroti. Dental features reveal the existence of an unsuspected Asian Pleistocene clade, referred to as Nesorhinus gen. nov.. It includes the rhinoceros from the Philippines and another extinct species from Taiwan, N. hayasakai. Nesorhinus is the sister-group to a cluster comprising Dicerorhinus and Rhinoceros. Our phylogenetic results strongly suggest an island-hopping dispersal for Nesorhinus, from the Asian mainland towards Luzon via Taiwan by the Late Miocene or later, and Pleistocene dispersals for representatives of Rhinoceros. Nesorhinus philippinensis would be the first perissodactyl species supporting the island-rule hypothesis, with decreased body weight and limb-bone robustness.

Origin and Demographic History of Philippine Pigs Inferred from Mitochondrial DNA

“…One is via NEA through Taiwan, in parallel with the Neolithic expansion into ISEA and Oceania, and the other is via Southeast Asia, particularly from the Indochinese Peninsula via the Sundaic Region (Sundaland) to Palawan and Sulu Archipelago, which spread to the rest of the Philippine islands since prehistoric times. The latter could be consistent with the previously suggested north to south dispersal pattern ( Koenigswald, 1956 ; Arenas et al, 2020 ; Antoine et al, 2021 ), while the former might agree the dispersal routes proposed by ( Porr et al, 2012 ; Mijares, 2014 ; Louys et al, 2018 ; Arenas et al, 2020 ). Despite geographic barriers to migration, these animals have been able to expand their range across the various islands of the Philippines, and variation in morphological patterns has evolved among these populations.…”

An Early Miocene skeleton ofBrachydiceratheriumLavocat, 1951 (Mammalia, Perissodactyla) from the Baikal area, Russia, and a revised phylogeny of Eurasian teleoceratines

“…Character distribution at each node and corresponding indices are detailed in S2. Suprageneric relationships within Rhinocerotinae are consistent with those proposed by Antoine (2002, Antoine et al (2010Antoine et al ( , 2022, Becker et al (2013), and Pandolfi et al (2021: Plesiaceratherium mirallesi is the earliest offshoot among Rhinocerotinae (node 1; 26 unambiguous synapomorphies; Bremer Support [BS] > 5). Aceratheriini (node 3; nine unambiguous synapomorphies; BS = 2) and Rhinocerotini (node 5; eight unambiguous synapomorphies; BS = 2) are sister clades (node 2; 13 unambiguous synapomorphies; BS = 4).…”

“…Aside from the outgroup, we have included a branching group (Antoine, 2002, 2003; Orliac et al, 2010; Boivin et al, 2019), consisting of 12 species classically assigned to all suprageneric groups but Teleoceratina among Rhinocerotinae, and aimed at i) further testing the monophyly of the in-group and ii) replacing it among Rhinocerotinae. The branching group includes an early-diverging representative of Rhinocerotinae ( Plesiaceratherium mirallesi (Crusafont, Villalta & Truyols, 1955)), three species among Aceratheriini ( Aceratherium incisivum Kaup, 1832, Acerorhinus zernowi (Borissiak, 1914), and Alicornops simorrense (Lartet, 1851)), and eight members of the Rhinocerotina, encompassing all five living rhinoceroses, namely the Indian rhino ( Rhinoceros unicornis Linnaeus, 1758), the Javan rhino ( Rhinoceros sondaicus Desmarest, 1822), the Sumatran rhino ( Dicerorhinus sumatrensis (Fischer, 1814)), the white rhino ( Ceratotherium simum (Burchell, 1817)), and the black rhino ( Diceros bicornis (Linnaeus, 1758)), but also three fossil species: Lartetotherium sansaniense (Miocene of Europe; Heissig, 2012), Gaindatherium browni Colbert, 1934 (Miocene of South Asia; Heissig, 1972 ; Antoine, in press), and Nesorhinu s philippinensis (Von Koenigswald, 1956) (early Middle Pleistocene of the Philippines; Antoine et al, 2022 and references therein).…”

Adaptation to graviportality in Rhinocerotoidea? An investigation through the long bone shape variation in their hindlimb

“…1). To date, the relationships between the five modern taxa remain controversial, especially regarding the position of the Sumatran rhinoceros (Dicerorhinus sumatrensis) and its extinct relatives (e.g., Tougard et al, 2001;Orlando et al, 2003;Fernando et al, 2006;Price & Bininda-Emonds, 2009;Steiner & Ryder, 2011;Yuan et al, 2014;Welker et al, 2017;Cappellini et al, 2019;Antoine et al, 2021). These uncertainties are likely due to a hard polytomy at the base of the crown-group containing the five modern species (Willerslev et al, 2009;Gaudry, 2017).…”