• New fossils of small and medium-sized bovids from the Early Pleistocene Site of Shanshenmiaozui in Nihewan Basin, North China

    分类: 生物学 >> 动物学 提交时间: 2022-04-16 合作期刊: 《古脊椎动物学报》

    摘要:Shanshenmiaozui site in Nihewan Basin in North China is a recently discovered Early Pleistocene site which yields rich and diverse mammalian fossils. In the fauna, the small and medium-sized bovid fossils are well represented and can be referred to the following taxa: Spirocerus wongi, Gazella sinensis, Ovis shantungensis and Megalovis piveteaui respectively, among which G. sinensis is the dominate species. S. wongi and G. sinensis are mainly represented by horn-cores and partial skull bones as well as mandibles; in addition, metacarpal and/or metatarsal bones were also recognized for all of the four species. The horn-cores are easy to be identified to the species level, while the dentitions and the postcranial bones underwent a series of examinations and comparisons before getting properly determined and referred to the most approximate taxa. Among the postcranial bones, the metapodials, especially to the metacarpal bones special attentions were paid, which are crucial not only for taxonomic identification, but also for phylogenetic and paleoecological reconstructions; the previously misidentified metapodial specimens in Nihewan fauna were reconsidered in this paper. In the SSMZ fauna, the bovid guild is dominated by Gazella and Bison, which indicates steppe was the most important biome in Nihewan Basin during Early Pleistocene.

  • New fossils of Late Pleistocene Sus scrofa from Yangjiawan Cave 2, Jiangxi, China

    分类: 生物学 >> 动物学 提交时间: 2020-09-15 合作期刊: 《古脊椎动物学报》

    摘要:The YJW (Yangjiawan) Cave 2 of Pingxiang in Jiangxi Province is a karst cave that developed in the Permian limestone of the Changxing Formation, which is filled with clay and grit of Late Pleistocene age. Six excavations have been conducted at the site since 2015. More than ten thousand mammalian fossils have been unearthed, and the wild boar fossils account for approximately 49%, which represents the richest wild boar fossil tooth collection of Pleistocene age in southern China. This study focuses on the studies of the canine teeth and the third molars, and mainly compares fossils of Sus peii and S. xiaozhu in South China and the data of extant S. scrofa respectively in dental morphology and odontometric data analyses which includes scatter plot analysis, regression analysis, coefficient of variation analysis and linear discriminant analysis. The typical scrofic type of the male’s lower canine teeth confirmed the identification of the suid fossils from YJW Cave 2 as S. scrofa. Although the male’s lower canines, the M2s and m3s, are among the most variable teeth in sizes, they stay in the ranges of S. scrofa; furthermore, the scatterplots of both the upper and lower third molars form two distinct clusters respectively, which can probably be attributed to sexual dimorphism rather than resulting from a mixture of different suid species. The post-Early Pleistocene suid fauna in southern China is almost only composed of S. scrofa, which is quite different from the adjacent Southeast Asia where the suid fauna is quite taxonomically diversified and dominated by the verrucosic type.

  • New fossils of Bos primigenius (Artiodactyla, Mammalia) from Nihewan and Longhua of Hebei, China

    分类: 地球科学 >> 地质学 提交时间: 2017-08-24 合作期刊: 《古脊椎动物学报》

    摘要: The new fossils of Bos primigenius in this study came from two regions in Hebei Province: Nihewan Basin (one partial skull with right horn-core and one humerus) and Longhua County (one humerus, one tibia, 2 calcanea and 3 astragali). The humerus from Nihewan has a total length of 457.3 mm, which almost represents the largest aurochs individual which has a two-meter shoulder height. The biggest humerus and other big cranial specimens in northern China can be correlated with the European counterparts of late Middle Pleistocene, and they should be contemporary. The smaller sized limb-bones from Longhua were unearthed from loess deposits, which can be attributed to Late Pleistocene. The current knowledge shows that aurochs may have arrived in China earlier than Late Pleistocene, because its associated taxa, e.g. Canis lupus, Panthera tigris, Mammuthus primigenius, Equus caballus, Coelodonta antiquitatis, Sus scrofa, Camelus knoblochi, Cervus elaphus, Alces alces and Bison priscus have appeared as early as late Middle Pleistocene or even earlier in Eastern Europe and Northern Eurasia. Furthermore, new numerical dating results show that the aurochs’ occurrences from some sites in China can be traced back to Middle Pleistocene. This study proposes that the larger sized aurochs should be of a late Middle Pleistocene age. In China, aurochs fossils mainly occur in the northern part and the transitional zone along the Huaihe River, but are absent in southern China and Southeast Asia, which resulted in the hypothesis of “Central Asian Corridor” through which aurochs reached China. In recent years as more bovini fossils were recovered in Africa, the Bos phylogeny was proposed, which assumed that the evolution of Bos lineage took place in Africa rather than in Eurasia as thought before, and the earliest ancestor of B. primigenius is Pelorovis turkanensis, finally the genus Bos dispersed into Eurasia at the beginning of the Middle Pleistocene. The present authors think that the African Pelorovis species are too different from the Bos lineage in morphology; on the contrary, the early Bos species from Siwalik in South Asia resembles B. primigenius very much. In China, most of the B. primigenius fossils were recovered from fluvio-lacustrine deposits in North China Plain, Loess Plateau and Song-Nen Plain, whereas few of them were from loess deposit, which means that the aurochs fossils could be employed as an indicator of warm climate and wet environment. 原始牛(Bos primigenius)化石新材料包括泥河湾盆地禾尧庄的1件角心、上沙嘴的1件肱骨和承德隆化的1件肱骨、1件胫骨、1件踝骨、2件跟骨和3件距骨;其中上沙嘴的肱骨化石长达457.3 mm, 代表迄今在我国境内发现的最大原始牛个体,也是该种的最大记录之一,推算其所属动物的肩高接近2 m; 北京门头沟珠窝的原始牛头骨的眶后宽度及角心周长数据也是该种的最大记录之一;禾尧庄的角心标本稍小,但也比晚更新世多数同类要大;这些巨大的化石与欧洲中更新世晚期同类十分接近,其时代也应当与之相当,为中更新世晚期;过去认为原始牛在我国只出现于晚更新世地层,但现在看来该种在中更新世晚期就已扩散到中国。东欧及北亚的最新化石证据表明,过去认为与原始牛共生的晚更新世化石组合的常见属种早在中更新世晚期或更早时期就已出现,其中包括灰狼、虎、真猛犸象、马、真披毛犀、野猪、诺氏驼、赤鹿、驼鹿及草原野牛等。最新测年数据也表明中国北方有几个含原始牛化石的遗址是形成于中更新世晚期;本文认为华北和西北地区个体巨大的原始牛,代表中更新世晚期,而个体较小的则可能代表晚更新世或全新世;近些年在东北地区发现大量原始牛化石,但其中少见个体巨大者。在我国,原始牛化石分布只局限于北方及淮河过渡区,而在南方及毗邻的东南亚地区均未发现此类化石;因此,有人提出原始牛很可能是在中更新世中、晚期通过中亚走廊(Central Asian Corridor)进入中国。不过,近些年在非洲也发现了一些牛属(Bos)化石,因此有人又提出了牛属非洲起源的“奥杜威牛–牛属演化谱系”(Pelorovis–Bos lineage), 但该学说所依据的奥杜威牛化石材料,在形态结构上与牛属相去甚远,难以归入同类;此外,非洲可靠的牛属化石记录均未超过1 Ma。本文作者支持传统的牛属“南亚起源学说”,因为在南亚西瓦里克地区发现的早期牛属化石不仅时代更古老(早于2 Ma), 并且在形态上与原始牛更为相似。中国北方的原始牛化石主要发现于华北平原、黄土高原和松嫩平原的河湖相堆积层,仅极个别出现于黄土地层;由此推断原始牛可能更喜欢水系发育的林缘和/或沼泽环境。

  • Association of echocardiographic left ventricular structure and-344C/T aldosterone synthase gene variant: A meta-analysis

    分类: 生物学 >> 生物物理学 提交时间: 2016-05-15

    摘要:Background: Aldosterone synthase (CYP11B2) is one of the most studied candidate genes related to essential hypertension (EH) and left ventricular hypertrophy (LVH). Some studies have focused on the relationship between -344C/T polymorphism (rs1799998) in the CYP11B2 gene and LVH, but the results are controversial. This meta-analysis is purposed to reveal the relationship between the -344C/T and the left ventricular structure and function, including left ventricular end diastolic dimension (LVEDD), left ventricular end systolic diameter (LVESD), left ventricular mass/left ventricular mass index (LVM/LVMI), left ventricular posterior wall thickness (LVPWT), and interventricular septal wall thickness (IVS). Methods: A literature search of PubMed and Embase databases was conducted on articles published before January 27, 2014. The odds ratios with 95% confidence intervals were calculated. Heterogeneity analyses were performed using meta-regression. Tests for publication bias were also performed and biased studies should be removed from subsequent analyses. Results: There were 20 studies with a total of 6780 subjects meeting the inclusion criteria. The main finding was that concentration levels of LVEDD and LVESD were higher in CC homozygous individuals than in TT homozygous individuals in the whole group. In the Asian subgroup, TT homozygous individuals had larger IVS than CC homozygous individuals. In the Caucasian normotension subgroup, CC homozygous individuals had larger LVM/LVMI than TT homozygous individuals. In the Asian essential hypertension subgroup, TT homozygous individuals had larger LVPWT values than CC homozygous individuals. Conclusions: The present findings support the hypothesis that CC homozygous individuals may have greater left ventricular diameters (LVEDD and LVESD) regardless of their ethnicities or physical conditions.