シャンシ (中国) の基礎カンブリア期のミオファウナルのデウテロストームです
Jian Han1, Simon Conway Morris2, Qiang Ou3,4
1State Key Laboratory of Continental Dynamics, Department of Geology, Northwest University, Xi'an 710069, China.
Nature
|January 31, 2017
まとめ
初期のカンブリア期の化石,サッコーライトス・コロナリウスは,デウテロストームの進化の鍵を明らかにしています. これらの化石は,側開口が初期デウテロストームの発達と機能に不可欠であったことを示唆しています.
科学分野:
- パレオントロジー・パレオントロジー
- 進化生物学の進化生物学について
- 生命の初期形態について
背景:
- 脊椎動物を含むデュテロストームは,カンブリア時代の様々な形態を含んでいる.
- 最古のデウテロストームとその進化的中間体の性質については,依然として議論が続いている.
- 初期のデウテロストームの化石証拠は,しばしば論争の的である.
研究 の 目的:
- 最古のカンブリア時代から,新しい化石種,サッコリュタス・コロナリウス (Saccorhytus coronarius) を記述するために.
- 初期デウテロストームの進化を理解する上でサッコリュタスの潜在的な役割を調査する.
- デウテロストームの起源における横の開口の重要性を探求する.
主な方法:
- 中国南部のオルステンのような Lagerstätte のミリメートルの化石の分析.
- ストラティグラフィック・デッティングにより,化石はカンブリア紀の初期に位置する.
- 既知のデウテロストーム群との比較形態学的分析.
主要な成果:
- 新しい属と種であるSaccorhytus coronariusの発見.
- Saccorhytusは口と並べられた側面の開口を持つ袋状の身体を示し,門がない可能性があります.
- ベトゥリコリアンとベトゥロシスティドとの形態学的類似性が確認された.
結論:
- 横開きの開口の発達は,デウテロストームの進化における重要な一歩であり,おそらく喉として採用された.
- Saccorhytusのミエオファウナルの習慣は,化石と分子時計の分岐推定値の間の不一致を調和させることができる.
- これらの発見は,デウテロストームの起源と初期の多様化についての洞察を提供します.
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