A New Species ofAgriotheriumfrom North America, and Implications for Understanding Transformations in the Metaconid-Entoconid Complex of Bears

doi:10.1007/s10914-019-09480-x

	A New Species ofAgriotheriumfrom North America, and Implications for Understanding Transformations in the Metaconid-Entoconid Complex of Bears
	Jiangzuo, Qigao 1,2,3,4; Flynn, John J.4
刊名	JOURNAL OF MAMMALIAN EVOLUTION
	2020-12-01
卷号	27 期号:4 页码:775-787
关键词	Agriotherium Indarctos Ursidae Miocene Hemphillian NALMA Quiburis Formation Metaconid-entoconid complex
ISSN号	1064-7554
DOI	10.1007/s10914-019-09480-x
英文摘要	New material ofAgriotheriumfrom the late Hemphillian (~6 Ma) Quiburis Formation in Arizona, North America is reported. These specimens represent a new species,Agriotherium hendeyi, sp. nov., of small size and with a bucco-lingually narrow lower dentition distinguishing it from North American "Agriotherium"schneiderias well as the genotype and other Old World species ofAgriotherium. Strikingly, the m1 metaconid-entoconid complex of the new species exhibits a morphologically transitional state between the pattern observed inIndarctos(three cusps) and the typicalAgriotheriumpattern (two cusps). Together with a review of the variation inA. africanum, a geometric morphometric analysis permits identification and discussion of a proposed transformation pathway from theIndarctospattern to theAgriotheriumpattern. It is shown that the two cusps in the metaconid-entoconid complex inAgriotheriumcorrespond to the two entoconids inIndarctos, whereas the ancestral metaconid is reduced or lost inAgriotherium. From a developmental perspective, the metaconid fused to the anterior entoconid as a result of the shortening of the talonid, rather than via replacement of the metaconid by a posterior shift of the entoconid, presumably under selective pressure towards a more typically hypercarnivorous tooth morphology and carnivorous diet.
WOS关键词	MAMMALIAN DENTITION ; TEETH ; EVOLUTION ; PATTERNS ; LINES ; FAUNA
WOS研究方向	Evolutionary Biology ; Zoology
语种	英语
出版者	SPRINGER
WOS记录号	WOS:000579835600012
内容类型	期刊论文
源URL	[http://119.78.100.205/handle/311034/18143]
专题	中国科学院古脊椎动物与古人类研究所
通讯作者	Jiangzuo, Qigao
作者单位	1.Univ Chinese Acad Sci, Beijing 100049, Peoples R China 2.Chinese Acad Sci, Inst Vertebrate Paleontol & Paleoanthropol, Key Lab Vertebrate Evolut & Human Origins, Beijing 100044, Peoples R China 3.CAS Ctr Excellence Life & Paleoenvironm, Beijing 100044, Peoples R China 4.Amer Museum Nat Hist, Div Paleontol, New York, NY 10024 USA
推荐引用方式 GB/T 7714	Jiangzuo, Qigao,Flynn, John J.. A New Species ofAgriotheriumfrom North America, and Implications for Understanding Transformations in the Metaconid-Entoconid Complex of Bears[J]. JOURNAL OF MAMMALIAN EVOLUTION,2020,27(4):775-787.
APA	Jiangzuo, Qigao,&Flynn, John J..(2020).A New Species ofAgriotheriumfrom North America, and Implications for Understanding Transformations in the Metaconid-Entoconid Complex of Bears.JOURNAL OF MAMMALIAN EVOLUTION,27(4),775-787.
MLA	Jiangzuo, Qigao,et al."A New Species ofAgriotheriumfrom North America, and Implications for Understanding Transformations in the Metaconid-Entoconid Complex of Bears".JOURNAL OF MAMMALIAN EVOLUTION 27.4(2020):775-787.