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原始的なプラコデルマは,のある脊椎動物の顔の起源に光を当てています
Vincent Dupret1, Sophie Sanchez2, Daniel Goujet3
1Uppsala University, Department of Organismal Biology, Subdepartment of Evolution and Development, Norbyvägen 18A, SE-752 36, Uppsala, Sweden.
Nature
|February 14, 2014
まとめ
の脊椎動物の進化は,頭蓋骨の構造に明確な発達変化を伴いました. ロムンディナ (Romundina) のプラコダームの研究により,のない脊椎動物とを持つ脊椎動物の両方の特徴を組み合わせた原始的なの脊椎動物形態が明らかになった.
科学分野:
- 進化生物学の進化生物学について
- 発達生物学 発達生物学とは
- パレオントロジー・パレオントロジー
背景:
- 現存する脊椎動物は,のないサイクロストロマタとのあるグナソストロマタに分かれ,顔の発達が異なる.
- 主な発達上の違いには,鼻袋/鼻のプラコード起源と,エクトメセンキムの移動パターンが含まれる.
- 化石ののある脊椎動物は,のない形態からのある形態への進化のステップの洞察を提供します.
研究 の 目的:
- 先進的なイメージング技術を使用して,ロムンディーナのプラコダーマの頭蓋骨の解剖学を調査する.
- 初期ののある脊椎動物の原始的な頭蓋骨構造とその発達上の意味を理解する.
主な方法:
- 伝播相対照シンクロトロンマイクロトモグラフィーは,ロムンディナの頭蓋骨の解剖学をイメージするために使用されました.
- ロムンディナの頭蓋骨の特徴を,現存する脊椎動物と化石脊椎動物との比較分析.
主要な成果:
- Romundinaは,のない脊椎動物 (Cyclostomataとgaleaspids) に似た頭蓋骨と脳の比率を持つのある脊椎動物構造の組み合わせを示しています.
- このモザイクの解剖学は,を持つ脊椎動物の原始的な状態を示唆しています.
結論:
- の脊椎動物の起源は,エクトメンスキマの成長,増殖,脳の形状の変化の切り離しを伴う可能性があります.
- ロムンディナの解剖学は,脊椎動物の顔の発達の初期の進化を再構築するための重要な証拠を提供します.
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