Hippotherium Datum implies Miocene palaeoecological pattern

Tao Deng,Boyang Sun,Yan Liu,Shanqin Chen

doi:10.1038/s41598-022-07639-w

Abstract

Here, we report well–preserved skulls and postcranial specimens of genus Hippotherium from the Linxia Basin, Gansu, China. Based on morphological comparison, the species of Hippotherium in China, Hippotherium weihoense and Hippotherium chiai, should be ascribed to the same species, H. weihoense. We also reviewe other Old World hipparion species in the very early Late Miocene and figure out two evolutionary routes: the Hippotherium and Cormohipparion lineages. Analysis of locomotive ability indicates that H. weihoense likely lived in an open habitat, whereas other species of Hippotherium likely lived in closed habitats. This result shows a palaeoecological pattern in the early Late Miocene in Eurasia influenced by a series of geological events as aridification of mid–latitude Asia progressed, whereas Europe and North Africa remained relatively humid. As the genus originated from East Asia, hipparion horses divided rapidly into different groups with differing functional morphology to occupy diverse niches.

Highlights

Abbreviations HMV Hezheng Paleozoological Museum, Hezheng, China IVPP Institute of Vertebrate Paleontology and Paleoanthropology, Beijing, China AMNH American Museum of Natural History, New York, USA
The recent highaccuracy data of magnetostratigraphy performed by Fang et al.[16] provided an updated chronological framework for the Linxia Basin, with an absolute age for the lower boundary of the Guonigou Fauna of 11.5 Ma, which is the earliest record for a Hipparion-fauna in Eurasia
An et al.[38] argued that the northern part of the Tibetan Plateau had uplifted considerably in the early Late Miocene. They proposed that the northern part of the Tibetan Plateau appeared at 10–7 Ma, and that an important uplift/growth of the plateau occurred in the same period

Summary

Introduction

Lantian specimens and Fugu ones respectively attributed by L iu[10] and Li et al.[18] into H. chiai have subtriangular POFs. The dentition was regarded as another important feature to distinguish these two species in previous research.

Results

Conclusion