グナトストームと関連したデボニアン期ののない脊椎動物におけるランプリーのような
Philippe Janvier1, Sylvain Desbiens, Jason A Willett
1UMR 5143, CNRS, Muséum National d'Histoire Naturelle, CP38, 57 rue Cuvier, 75231 Paris Cedex 05, France. janvier@mnhn.fr
Nature
|April 28, 2006
まとめ
化石ののない魚エンデリオレピスは,魚に似た繊維を囲む袋を明らかにしています. この発見は,の袋が原始的な脊椎動物の特徴であり,の脊椎動物では失われている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
- 脊椎動物の進化について
- イクチオロジー イクチオロジー
背景:
- パレオゾーイク時代ののない脊椎動物 (オストラコダーム) は,の組織に関する直接的な証拠を欠いていた.
- 以前の知識は,状の状繊維の模糊な印象に依存していた.
研究 の 目的:
- 絶滅したのない脊椎動物の糸と袋の組織に関する最初の直接的な証拠を提供すること.
- 初期の脊椎動物における状構造の進化的影響を調査する.
主な方法:
- デヴォン後期ミガシャ Lagerstätteからの例外的に保存された化石のEndeiolepisの分析.
- 化石の状構造と現存する脊椎動物の状組織を比較した解剖学的研究.
主要な成果:
- エンドイオレピスの袋に閉じ込められた線によって支えられている可能性のある糸繊維の直接的な証拠の発見.
- Endeiolepisは,現存するランプレイに似たの組織を示しているが,の袋の数がかなり多い.
- この発見は,の袋が原始的な脊椎動物の特徴であり,その後の脊椎動物に失われたことを示しています.
結論:
- Endeiolepisの袋の存在は,脊椎動物におけるその原始的な性質を支持しています.
- のある脊椎動物における袋の喪失は,重要な進化的差異を表しています.
- この発見は,脊椎動物の呼吸器系の初期の進化に関する新しい洞察を提供します.
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