Paleontological study on the early phase of Cambrian Explosion based on the small shelly fossils and ichnofossils

基于小贝化石和化石的寒武纪大爆发早期古生物学研究

• 批准号: 21540482
• 负责人: OJI Tatsuo
• 金额: $ 2.75万
• 依托单位: Nagoya University (2010-2011)The University of Tokyo (2009)
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2009
• 资助国家: 日本
• 起止时间: 2009 至 2011
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-21540482/
• 关键词: カンブリア紀; 多細胞動物の多様化; 進化; 生痕化石; 小型有殻化石; ニューファンドランド; 貴州省; ゴビ・アルタイ; 多細胞動物; 多様化; 中国; 貴州; 適応放散

We investigated pattern of rapid evolution of metazoa occurred in the Early Cambrian, based on the ichnofossils and small shelly fossils sampled or observed from Newfoundland, Canada, Guizhou and Yunnan provinces, China and Gobi-Altai, Mongolia. As a result, following three things were clarified. 1. Two-staged, stepwise increase in the diversity and bedding plane bioturbation index were detected in the Treptichnus pedum and the Rusophycus avalonensis zones, the lowest biozones in the Lower Cambrian. In these zones, there were no development of a clear differentiation of ichnofossils according to different sedimentary facies, and also there is no clear ichnofossils detected on the upper surface of microbial mats. 2. Based on the detailed morphological studies on the protoconodonts from the lower Meishucun Stage in Yunnan Province, some of these are considered as grasping spines of chaetognaths(arrow worms). This discovery in turn suggests that there were predatory animals present in the mid-water column of the pelagic environment in the Early Cambrian. 3. We compared ichnofossils from two late Early Cambrian formations(Chintingshan and Balang), the former formation deposited slightly shallower environment than the latter. In this time, there was already differentiation of ichnofossils according to the different environments, which character was not detected in the ichnofossils from the earliest Cambrian of Newfoundland.

我们根据从加拿大纽芬兰省、中国贵州省和云南省以及蒙古戈壁-阿尔泰地区采样或观察到的化石和小型贝壳化石，研究了早寒武世后生动物快速演化的模式。结果，澄清了以下三件事。 1. 下寒武统最低生物带Treptichnus pedum和Rusophycus avalonensis带的多样性和层理面生物扰动指数呈两阶段逐步增加。这些区域没有发育出明显的不同沉积相的化石化石，微生物席上表面也没有发现明显的化石化石。 2.根据对云南省梅树村下阶段的原牙形动物的详细形态学研究，认为其中一些属于毛颌类（箭虫）的抓刺。这一发现反过来表明，早寒武世中上层水层中存在掠食性动物。 3、比较了早寒武世晚期的两个地层（金亭山地层和巴朗地层）的化石化石，前地层的沉积环境比后者略浅。此时，化石已根据环境的不同而出现分化，而这一特征在纽芬兰最早寒武纪的化石中并未发现。

项目成果

カンブリア紀最初期の動物多様化と化石記録:ニューファンドランド、中国およびモンゴルのデータより

早寒武世动物多样化和化石记录：来自纽芬兰、中国和蒙古的数据

• 发表时间: 2012
• 作者: 大路樹生;望月貴史;David Casenove
• 通讯作者: David Casenove

Preface for the symposium" The Mesozoic revolution : a global biologic transformation"

研讨会序言“中生代革命：全球生物转型”

• 发表时间: 2011
• 期刊: Paleontological Research
• 影响因子: 0.9
• 作者: Oji;T. and Amano;K
• 通讯作者: K

生痕化石の多様化から探るカンブリア爆発の解明

从遗迹化石的多样化阐释寒武纪大爆发

• 发表时间: 2010
• 作者: Nakazawa;T.;小野展嗣;望月貴史・大路樹生
• 通讯作者: 望月貴史・大路樹生

Preface (The Mesozoic revolution : a global biologic transformation)

前言（中生代革命：全球生物转型）

• DOI: 10.2517/1342-8144-15.2.053
• 发表时间: 2011
• 期刊: Paleontological Research
• 影响因子: 0.9
• 作者: Oji;T.;Amano;K
• 通讯作者: K

Staging of regeneration process of an arm of the feather star Oxycomn thus japonica focusing on oral-aboral boundary

羽星 Oxycomn 臂的再生过程分期，因此 japonica 着眼于口-口边界

• 发表时间: 2010
• 期刊: Developmental Dynamics
• 影响因子: 2.5
• 作者: Shibata;T.F.;Oji;T.;Akasaka;K.;Agata;K.
• 通讯作者: K.