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1. chinaXiv:201906.00053 [pdf]

New material of thelodonts from Lochkovian(Lower Devonian) of Qujing, Yunnan, China

CUI Xin-Dong(1,2,3); LI Qiang(4); QIAO Tuo(1,2); ZHU Min(1,2,3)
Subjects: Biology >> Zoology

We reconstructed a wealth of three-dimensional virtual models of vertebrate microremains from the Xitun Formation and lower part of the Xishancun Formation (Lochkovian,Lower Devonian) of Qujing, Yunnan by means of high-resolution computed tomography. One genus (Parathelodus) and seven species (P. trilobatus, P. asiaticus, P. cornuformis, P. scitulus, P. xitunensis sp. nov., P. wangi sp. nov. and P. liaokuoensis sp. nov.) of thelodonts are described. The new discovery extends the stratigraphic distribution of Parathelodus from the Xitun Formation and the upper part of the Xishancun Formation to the lower part of the Xishancun Formation, the horizon close to the Silurian-Devonian boundary. The three new species, P. xitunensis, P. wangi and P. liaokuoensis, enhance our knowledge of the thelodont diversity from the Early Devonian of China.

submitted time 2019-06-17 From cooperative journals:《古脊椎动物学报》 Hits103Downloads39 Comment 0

2. chinaXiv:201906.00025 [pdf]

The tetrapod fauna of the upper Permian Naobaogou Formation of China— 4. the diversity of dicynodonts

LIU Jun
Subjects: Biology >> Zoology

The Permian dicynodont records were previously rare in North China, but many dicynodont specimens have been collected from the Naobaogou Formation in Daqingshan area, Nei Mongol since 2009. Among these specimens, seven morphotypes have been identified, and they may represent seven different species: two of them are closely related to Daqingshanodon limbus, three or four are closely related to Jimusaria sinkianensis, and one may be closely related to Turfanodon. This study shows the dicynodonts also have a high diversity at the species level in North China.

submitted time 2019-06-11 From cooperative journals:《古脊椎动物学报》 Hits210Downloads106 Comment 0

3. chinaXiv:201906.00026 [pdf]

Molecular clock dating using MrBayes

ZHANG Chi
Subjects: Biology >> Zoology

This paper provides an overview and a protocol of molecular clock dating using MrBayes. Two modern approaches, total-evidence dating and node dating, are demonstrated using a truncated dataset of Hymenoptera with molecular sequences and morphological characters. The similarity and difference of the two methods are compared and discussed. Besides, a non-clock analysis is performed on the same dataset to compare with the molecular clock dating analyses.

submitted time 2019-06-11 From cooperative journals:《古脊椎动物学报》 Hits209Downloads108 Comment 0

4. chinaXiv:201906.00027 [pdf]

Metatarsal II osteohistology of Xixianykus zhangi (Theropoda: Alvarezsauria) and its implications for the development of the arctometatarsalian pes

QIN Zi-Chuan; ZHAO Qi; XU Xing
Subjects: Biology >> Zoology

The late-branching alvarezsaurian Xixianykus zhangi is among the smallest known non-avialan theropods. With great similarity to its close relatives, it is highly cursorial as indicated by proportionally long lower segments of the hindlimbs and the presence of an arctometatarsalian pes–a highly modified structure that has been suggested to improve cursorial capability in theropods. Here we describe the osteohistology of the metatarsal II of the holotype of X. zhangi (XMDFEC V 0011). Two rarely reported histological features, radial vascular canals and Sharpey’s fibers, are presented in this study. We suggest that both features are related to the development of the arctometatarsalian pes; however, further investigations of metatarsal osteohistology in theropods are required for the validation of our interpretation.

submitted time 2019-06-11 From cooperative journals:《古脊椎动物学报》 Hits205Downloads95 Comment 0

5. chinaXiv:201906.00028 [pdf]

Cladistic approach on chronological relationship of the Pleistocene mammalian faunas from China

DONG Wei; LIU Wen-Hui; BAI Wei-Peng
Subjects: Biology >> Zoology

There are many localities yielding the Pleistocene mammalian faunas in China. It offers excellent material for the study of mammalian evolution, biochronology,paleoecology,paleoenvironment, paleozoogeography, etc. Faunal assemblage characters and taxonomic extinction rates were widely used for determining the faunal ages in biochronology. Faunal binary similarity coefficients sequenced according to Brainerd-Robinson’s rule and antiquity coefficients were further developed methods in biochronology for dating the faunal ages. The faunal binary similarity coefficients are based on the presence or absence of a taxon in a fauna. It is similar to the presence or absence of a character of a species in cladistic analyses for phylogeny, and all faunas have a special ancestor-descendant relationship. The present work is an attempt to find the relationship of the faunas with cladistic methods by selecting three groups of faunas sequenced by faunal binary similarity coefficients according to Brainerd-Robinson’s rule and antiquity coefficients, to compare the results with different methods, and then to estimate the ages of the faunas not yet dated by physical or chemical methods. The estimations are as follow: Gulongshan in Dalian, Liaoning Province: 16–20 ka; Shanchengzi at Benxi, Liaoning Province: 20–30 ka; Hualongdong at Dongzhi Man site, Anhui Province: 150–400 ka; Xinghuashan at Nanzhao Man site, Henan Province: 150–400 ka; Donghe at Luonan Man site, Shaanxi Province: 500–700 ka; Bailongdong at Yunxi Man site, Hubei Province: 500–850 ka; Meipu at Yunxian, Hubei Province: 500–850 ka; Mohui at Tiandong Man site, Guangxi Autonomous Region: 1.2–1.8 Ma; Juyuandong at Liucheng, Guangxi Autonomous Region: 1.2–1.5 Ma; Chutoulang at Chifeng, Nei Mongol Autonomous Region: 1.6–1.9 Ma; Renzidong at Fanchang, Anhui Province: 1.9–2.4 Ma.

submitted time 2019-06-11 From cooperative journals:《古脊椎动物学报》 Hits212Downloads103 Comment 0

6. chinaXiv:201906.00095 [pdf]

Molecular clock dating using MrBayes

ZHANG Chi
Subjects: Biology >> Zoology

This paper provides an overview and a protocol of molecular clock dating using MrBayes. Two modern approaches, total-evidence dating and node dating, are demonstrated using a truncated dataset of Hymenoptera with molecular sequences and morphological characters. The similarity and difference of the two methods are compared and discussed. Besides, a non-clock analysis is performed on the same dataset to compare with the molecular clock dating analyses.

submitted time 2019-06-11 From cooperative journals:《古脊椎动物学报》 Hits85Downloads42 Comment 0

7. chinaXiv:201906.00096 [pdf]

Metatarsal II osteohistology of Xixianykus zhangi (Theropoda: Alvarezsauria) and its implications for the development of the arctometatarsalian pes

QIN Zi-Chuan; ZHAO Qi; XU Xing
Subjects: Biology >> Zoology

The late-branching alvarezsaurian Xixianykus zhangi is among the smallest known non-avialan theropods. With great similarity to its close relatives, it is highly cursorial as indicated by proportionally long lower segments of the hindlimbs and the presence of an arctometatarsalian pes–a highly modified structure that has been suggested to improve cursorial capability in theropods. Here we describe the osteohistology of the metatarsal II of the holotype of X. zhangi (XMDFEC V 0011). Two rarely reported histological features, radial vascular canals and Sharpey’s fibers, are presented in this study. We suggest that both features are related to the development of the arctometatarsalian pes; however, further investigations of metatarsal osteohistology in theropods are required for the validation of our interpretation.

submitted time 2019-06-11 From cooperative journals:《古脊椎动物学报》 Hits105Downloads51 Comment 0

8. chinaXiv:201906.00097 [pdf]

Cladistic approach on chronological relationship of the Pleistocene mammalian faunas from China

DONG Wei; LIU Wen-Hui; BAI Wei-Peng
Subjects: Biology >> Zoology

There are many localities yielding the Pleistocene mammalian faunas in China. It offers excellent material for the study of mammalian evolution, biochronology,paleoecology,paleoenvironment, paleozoogeography, etc. Faunal assemblage characters and taxonomic extinction rates were widely used for determining the faunal ages in biochronology. Faunal binary similarity coefficients sequenced according to Brainerd-Robinson’s rule and antiquity coefficients were further developed methods in biochronology for dating the faunal ages. The faunal binary similarity coefficients are based on the presence or absence of a taxon in a fauna. It is similar to the presence or absence of a character of a species in cladistic analyses for phylogeny, and all faunas have a special ancestor-descendant relationship. The present work is an attempt to find the relationship of the faunas with cladistic methods by selecting three groups of faunas sequenced by faunal binary similarity coefficients according to Brainerd-Robinson’s rule and antiquity coefficients, to compare the results with different methods, and then to estimate the ages of the faunas not yet dated by physical or chemical methods. The estimations are as follow: Gulongshan in Dalian, Liaoning Province: 16–20 ka; Shanchengzi at Benxi, Liaoning Province: 20–30 ka; Hualongdong at Dongzhi Man site, Anhui Province: 150–400 ka; Xinghuashan at Nanzhao Man site, Henan Province: 150–400 ka; Donghe at Luonan Man site, Shaanxi Province: 500–700 ka; Bailongdong at Yunxi Man site, Hubei Province: 500–850 ka; Meipu at Yunxian, Hubei Province: 500–850 ka; Mohui at Tiandong Man site, Guangxi Autonomous Region: 1.2–1.8 Ma; Juyuandong at Liucheng, Guangxi Autonomous Region: 1.2–1.5 Ma; Chutoulang at Chifeng, Nei Mongol Autonomous Region: 1.6–1.9 Ma; Renzidong at Fanchang, Anhui Province: 1.9–2.4 Ma.

submitted time 2019-06-11 From cooperative journals:《古脊椎动物学报》 Hits96Downloads53 Comment 0

9. chinaXiv:201901.00103 [pdf]

Cranial osteology of Beipiaosaurus inexpectus (Theropoda: Therizinosauria)

LIAO Chun-Chi(1,2,3); XU Xing(1,2)
Subjects: Biology >> Zoology

Beipiaosaurus inexpectus, a key taxon for understanding the early evolution of therizinosaurians, has not been fully described since it was briefly reported on by Xu, Tang and Wang in 1999. Here we present a detailed description of the cranial anatomy of the holotype of this theropod dinosaur. B. inexpectus is unique in some of its cranial features such as the postorbital process of the frontal is large and its abrupt transition from the orbital rim, a long and sharp anterior process of the parietal, the elongate ventral ramus of the squamosal process of parietal, and external mandibular fenestra deep dorsoventrally and extremely posteriorly located. A number of plesiomorphic cranial features (such as relatively large dentary and less downturned degree of dentary symphysis) suggest that B. inexpectus is an early-branching Therizinosaurian, as proposed by previous studies. New information derived from our study is not only important for our understanding of the cranial anatomy of B. inexpectus but also significant to the study of the evolution of Therizinosauria.

submitted time 2019-01-16 From cooperative journals:《古脊椎动物学报》 Hits427Downloads5 Comment 0

10. chinaXiv:201812.00640 [pdf]

菊粉的生理功能及其在畜禽生产中的应用

陈佳亿(1); 陈凤鸣(1); 欧淑琦(1); 赵玉蓉(1)
Subjects: Biology >> Zoology

菊粉是一类植物源性的天然果聚糖,具有平衡肠道微生物、调节免疫和脂质代谢以及促进矿物质吸收等作用。作为一种天然的饲料添加剂,菊粉有改善畜禽肠道健康、提高免疫力等功效,具有良好的应用前景。本文综述了菊粉的理化性质、提取工艺、主要生理功能及其在畜禽生产中的应用状况,以期为菊粉在畜禽饲料中的应用提供参考。

submitted time 2018-12-25 From cooperative journals:《动物营养学报》 Hits2023Downloads352 Comment 0

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