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Mammalian Fossils (mammalian + fossil)

Distribution by Scientific Domains
Earth and Environmental Science75%

Selected Abstracts

Geological age of the Yokawa Formation of the Kobe Group (Japan) on the basis of terrestrial mammalian fossils

ISLAND ARC, Issue 3 2007
Takehisa Tsubamoto
Abstract The age of the Yokawa Formation of the Cenozoic Kobe Group distributed in Hyogo Prefecture of western Japan based on mammalian fossils is discussed. Two fossil dental specimens of terrestrial mammals discovered from the lowest part of the Yokawa Formation in the Sanda area are described. These two fossils described here are: (i) a right mandibular fragment with p2,m3 of Bothriodon sandaensis sp. nov. (selenodont anthracotheriid artiodactyl), which appears to be the most primitive among the species of the genus; and (ii) right m1,m3 of cf. Hyrachyus sp. (primitive rhinocerotoid perissodactyl). In the lower part of the Yokawa Formation, Zaisanamynodon (amynodontid perissodactyl) was previously reported. The morphology (,evolutionary stage') of B. sandaensis is indicative of the latest Middle to Late Eocene, that of cf. Hyrachyus sp. is indicative of the Early to Middle Eocene, and Zaisanamynodon is indicative of the Late Middle to Late Eocene. Therefore, the fossil mammals of the Yokawa Formation indicate an latest Middle Eocene (ca. 38 Ma) correlation for the lower part of the formation, as a working hypothesis. Although the resolution of the geological age based on these mammalian fossils is relatively low compared to that based on marine index fossils, this result is concordant with the recent radiometric correlation of the lower part of the Yokawa Formation in the Sanda area. [source]

Earliest Miocene hominoid from Southeast Asia

AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 2 2004
Yutaka Kunimatsu
Abstract A new hominoid fossil site, Chiang Muan in northern Thailand, yielded the first finding of a large-bodied Miocene hominoid in Southeast Asia. This specimen (CMu6-1,00) was preliminarily reported by Kunimatsu et al. ([2000a] Primate Res. 16:299). Later, Chaimanee et al. ([ 2003] Nature 422:61,65) reported additional hominoid teeth from the same site, but all of them were collected from younger deposits (the Upper Lignite Member, in Nagaoka and Suganuma [ 2002] Primate Res 18:159,164). The specimen described here (CMu6-1,00) was recovered from the Lower Lignite Member (Nagaoka and Suganuma [ 2002] Primate Res 18:159,164), which is probably several hundred thousand years older than the Upper Lignite Member (Suganuma et al. [ 2002] Primate Res. 18:165,173). This article provides a detailed description of this hominoid specimen and paleontological/geological data of the fossil site at Chiang Muan. The hominoid specimen (CMu6-1,00) is an isolated upper molar (right M1 or M2), similar in size to modern orangutans (Pongo pygmaeus). This upper molar has low and voluminous cusps, relatively thick enamel, and relatively low relief of the dentine/enamel junction, with only a faint remnant of the lingual cingulum. The age of Chiang Muan is estimated to be the latest Middle Miocene (ca. 11,12 Ma), based on the mammalian fossils (Nakaya et al. [ 2002] Primate Res. 18:131,141) and paleomagnetic study (Suganuma et al. [ 2002] Primate Res. 18:165,173). This suggests that the Chiang Muan Hominoid in the present study is an earlier member of Eastern Eurasian Miocene hominoids. Am J Phys Anthropol, 2003. © 2003 Wiley-Liss, Inc. [source]

Sequence of the Cenozoic Mammalian Faunas of the Linxia Basin in Gansu, China

ACTA GEOLOGICA SINICA (ENGLISH EDITION), Issue 1 2004
DENG Tao
Abstract In the Linxia Basin on the northeast margin of the Tibetan Plateau, the Cenozoic strata are very thick and well exposed. Abundant mammalian fossils are discovered in the deposits from the Late Oligocene to the Early Pleistocene. The Dzungariotherium fauna comes from the sandstones of the Jiaozigou Formation, including many representative Late Oligocene taxa. The Platybelodon fauna comes from the sandstones of the Dongxiang Formation and the conglomerates of the Laogou Formation, and its fossils are typical Middle Miocene forms, such as Hemicyon, Amphicyon, Platybelodon, Choerolophodon, Anchitherium, and Hispanotherium. The Hipparion fauna comes from the red clay of the Liushu and Hewangjia Formations, and its fossils can be distinctly divided into four levels, including three Late Miocene levels and one Early Pliocene level. In the Linxia Basin, the Hipparion fauna has the richest mammalian fossils. The Equus fauna comes from the Wucheng Loess, and it is slightly older than that of the classical Early Pleistocene Nihewan Fauna. The mammalian faunas from the Linxia Basin provide the reliable evidence to divide the Cenozoic strata of this basin and correlate them with European mammalian sequence. [source]