How did the trilobite see the world by using the Schizochroral eye?

三叶虫是如何用裂色眼看世界的？

• 批准号: 21740370
• 负责人: TANAKA Gengo
• 金额: $ 2.5万
• 依托单位: Gunma Museum of Natural History
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Young Scientists (B)
• 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-21740370/
• 关键词: 地層; 光学的古生物学; 光スイッチ; カンブリア紀; 進化; 例外的に保存の良い化石; 古生物; 節足動物; 機能形態学

By using an exceptionally preserved each ommatidia of the compound eye of the swimming trilobite genus Cyclopyge sp., I got exceptionally beautiful specimen cleaned to an accuracy of 20 um. First, I performed CT scaning of this specimen, got about 1, 200 sliced imaging dataset. Secondly, I made volume rendering image on the software(Molcer Plus), three three space coodinates were calculated on the 3D axes, and calculate normal vector of each 3D plane. Each origin of normal vector replaced to each center of ommatidium, and the optical axis of each ommatidium were determined. By makng globular chart of each optical axis, I estimated the visual field of the Cyclopyge sp. The result showed that the visual field of Cyclopyge sp. was narrow(about 120 degrees in each left and right lateral side) and their density was higher in the ventral side than the dorsal one. This result indicated that the Cyclopyge sp. was possible upside down swimmer.

利用保存完好的游泳三叶虫属Cyclopyge sp.复眼的每个小眼，我得到了非常漂亮的标本清洗到20微米的精度。首先，我对这个标本进行了CT扫描，得到了大约1200个切片的图像数据集。其次，在Molcer Plus软件上制作体绘制图像，在三维坐标轴上计算三个空间坐标，并计算每个三维平面的法向量。将每个法向量原点替换为每个小眼中心，并确定每个小眼的光轴。结果表明，剑水蚤的视野较窄（左右两侧各120 °），腹侧视野密度大于背侧视野密度。这一结果表明，Cyclopyge sp.可能是倒置游泳者。

项目成果

The Visual System and Paleoecology of the Silurian Ostracod Primitiopsis planifrons

• DOI: 10.1666/08-124.1
• 发表时间: 2009-05
• 作者: G. Tanaka;D. Siveter;A. Parker

Toshifumi Komatsu and Nguyen Duc Phong, Recent ostracod assemblages from the northeastern coast of Vietnam and the biogeographical significance of the euryhaline species

Toshifumi Komatsu 和 Nguyen Duc Phong，越南东北海岸的最新介形类群落以及广盐物种的生物地理学意义

• 期刊: Micropaleontology, accepted
• 作者: Gengo Tanaka;David Siveter and Andrew Parker;Gengo Tanaka;Gengo Tanaka;田中源吾;Gengo Tanaka;Gengo Tanaka
• 通讯作者: Gengo Tanaka

西南日本島根県中部中新統古江層から産出した介形虫化石群

日本西南部岛根县中部中新世古江组的幼虫化石

• 发表时间: 2009
• 期刊: 地質学雑誌 115
• 作者: Gengo Tanaka;Shin-ichi Nomura;田中源吾・野村律夫
• 通讯作者: 田中源吾・野村律夫

Original structural color preserved in an ancient leaf beetle

• DOI: 10.1130/g25353.1
• 发表时间: 2010-02
• 期刊: Geology
• 影响因子: 5.8
• 作者: G. Tanaka;H. Taniguchi;Haruyoshi Maeda;S. Nomura