コレカントの神経頭蓋骨の発達とサルコプテリガスの頭の進化
Hugo Dutel1,2, Manon Galland3, Paul Tafforeau4
1School of Engineering and Computer Science, Medical and Biological Engineering Research Group, University of Hull, Hull, UK. h.dutel@bristol.ac.uk.
Nature
|April 19, 2019
まとめ
この研究では コレカントスの脳がどのように発達するか示し ノトコルドが頭蓋骨の構造と頭蓋骨内関節に影響を与えることを示しています これはサルコプテリギウム魚の進化の 洞察力を与えてくれます
科学分野:
- 古生物学
- 発達生物学
- 比較解剖学
背景:
- サーコプテリジアン魚の脳は大きく進化し,頭蓋内関節があり,後に肺魚と初期の四足類に融合した.
- サルコプテリギアにおける神経の変異を誘発する発達メカニズムは十分に理解されていません.
- コレカントス (Latimeria) は頭蓋内関節を保持している唯一の生き物で,その神経頭蓋の発達は進化論の研究にとって極めて重要です.
研究 の 目的:
- ラティメリア・チャルマネの脳と脳神経形成を調査する
- 最も初期の段階から主要なオントジェネティック変化までの神経頭蓋骨の発達を記述する.
- 神経頭蓋骨の発達と軟組織との相互作用を解明する.
主な方法:
- 従来のX線とシンクロトロンX線マイクロコンピュータトモグラフィーを利用した.
- ラティメリアの広範囲な成長シリーズに磁気共鳴画像を用いた.
- 神経頭蓋骨と脳の発達を様々なオントジェネティック段階で調べました
主要な成果:
- ラティメリアの最も初期の発達段階における 神経頭蓋骨を記述した.
- オントゲニスの間に神経頭蓋骨の幾何学的な変化を記録した.
- 脳の大きさの極端な縮小とノトコルドの拡大が観察され,ノトコルドは頭蓋骨の部位に影響を与え,潜在的に頭蓋骨内関節を形成する.
結論:
- ノトコルドは,発達中の神経の形成に重要な役割を果たし,ラティメリアの頭蓋内関節形成を支える可能性があります.
- ラティメリアの脳脳の発達を理解することで サルコプテリジアン魚の脳脳の多様性の進化の洞察が得られます
- この研究は 脊椎動物の進化における 軟組織と骨格の発達との 重要な相互作用を強調しています
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