![\"Life](\"https:\/\/cdn.sci.news\/images\/enlarge13\/image_14425e-Taotienimravus-songi.jpg\")
<\/a><\/p>\nLife reconstruction of Taotienimravus songi in Chinese painting style. Image credit: Yuefeng Song.<\/p>\n
Taotienimravus songi lived in what is now China during the middle Oligocene, approximately 28 million years ago.<\/p>\n
The ancient species belongs to Nimravidae<\/a>, an extinct family of saber-toothed hypercarnivores, sometimes known as false saber-toothed cats<\/a>.<\/p>\n \u201cThe order Carnivora exhibits one of the widest ranges of body size diversity within Mammalia, spanning from approximately 50 g for the least weasel Mustela nivalis to an average of over three tons in the pinniped Mirounga,\u201d said Dr. Qigao Jiangzuo from the Institute of Vertebrate Paleontology and Paleoanthropology at the Chinese Academy of Sciences and colleagues.<\/p>\n \u201cWith few exceptions such as Ursidae, large-bodied terrestrial carnivores \u2014 particularly those exceeding 20 kg \u2014 typically adopt a macrocarnivorous diet, preying on large animals of comparable or greater size.\u201d<\/p>\n \u201cThe family Nimravidae, commonly referred to as false sabertooths, represents one of the earliest diverging lineages of Carnivora, characterized by large body size, hypercarnivorous craniodental morphology and presumably a macrocarnivorous diet,\u201d they added.<\/p>\n \u201cThe earliest confirmed fossil records of the family in the middle Eocene belong to already highly specialized species with felid-like craniodental morphology.\u201d<\/p>\n \u201cNimravidae underwent a radiation during the Eocene-Oligocene, with the best-preserved records found in North America, where numerous skulls and complete skeletons have been discovered.\u201d<\/p>\n \u201cFossil remains are also abundant in Eurasia but are less well preserved.\u201d<\/p>\n \u201cAs the first lineage of Carnivora to evolve large body size, Nimravidae is an ideal group to study exploration of the early macrocarnivorous niche by Carnivora in an environmental context vastly different from that of the modern world.\u201d<\/p>\n The skeletal remains of Taotienimravus songi were discovered in the Qingshuiying Formation in northern China.<\/p>\n The analysis of the specimens shows that the new species represents a non-sabertooth ecomorph form with initial bone-cracking adaptation \u2014 a unique form among the Nimravidae gamily.<\/p>\n The animal probably had a killing behavior that was different from any other felid-like carnivores but probably used a tearing bite as seen in hyenas.<\/p>\n \u201cThe most distinctive characters of the new nimravid are the very short and robust upper canine and the overall broad palatal region,\u201d the paleontologists said.<\/p>\n \u201cThe rostrum is very wide, probably one of the widest among the known nimravids.\u201d<\/p>\n \u201cUnlike in many other felid-like carnivores, the premolars are not reduced in size but instead enlarged, leaving no diastema between the canine and the cheek teeth.\u201d<\/p>\n \u201cThis contrasts with the condition in most felid-like carnivorans, where a diastema is almost invariably present.\u201d<\/p>\n \u201cWe interpret this gap as correlated with a strong canine bite and using canines to deeply puncture into the prey.\u201d<\/p>\n The team\u2019s phylogenetic analysis places Taotienimravus songi within Nimravinae, where it forms the sister lineage to European and North American Nimravus and Dinaelurus.<\/p>\n This clade is sister to the European lineage Eofelis + Dinailurictis + Quercylurus.<\/p>\n \u201cAn increase in body size among Nimravidae appears to have coincided with the demise of Oxyaenidae, another carnivorous clade in the Paleogene,\u201d the researchers said.<\/p>\n \u201cThe initial emergence of macrocarnivorous adaptation of Carnivora by a felid-like ecomorph probably reflects competition dynamics.\u201d<\/p>\n \u201cNimravidae successfully occupied several ecological niches that were not exploited by Felidae, probably owing to the lack of competition within Carnivora during much of their evolutionary history.\u201d<\/p>\n \u201cOur study underscores the role of both abiotic and biotic factors in shaping niche availability for these animals, emphasizing the need for discussions on niche change and evolution to be grounded in these considerations.\u201d<\/p>\n