の脊椎動物の祖先として,限界の歯と多重な皮膚の骨
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PubMedで要約を見る
まとめ
この要約は機械生成です。化石のを持つ脊椎動物 アカンソトラシドは 言語的に歯が付加され 前の理論に異議を唱えました この発見は 全てのの脊椎動物における 新しい祖先の歯の置換パターンを示唆しています
科学分野
- 古生物学
- 進化生物学
- 脊椎動物学
背景
- 現存する魚や陸上の脊椎動物における 歯の置換パターンは 顕著に変化しています
- 以前の仮説では,初期のの脊椎動物は,関節歯類に似た非縁の,放射的に並べられた歯のファイルを持っていたと示唆していた.
研究 の 目的
- 最古の歯を持つを持つ脊椎動物であるアカンソトラシドの 歯置換パターンを調べるため
- 全てのの脊椎動物の 祖先の歯の状態を決定する
主な方法
- シンクロトロンマイクロトモグラフィーは,化石の歯を分析するために使用されました.
- 考察された化石は,初期デボニアン期のラドティーナ,コソラスピス,トラマスピス属のものであった.
主要な成果
- アカントホラシドの歯は,の縁に沿って皮膚の骨に位置しています.
- アカンソトラシドの歯の付加は,言語的に発生し,後期の軟骨魚と骨魚と四足類で観察されたパターンです.
- これらの発見は 関節炎の歯のパターンと 根本的に異なっています
結論
- アカントソトラシドの限界的な,言語的に付加された歯のパターンは,すべてのを持つ脊椎動物の祖先条件として提案されています.
- これは昔から信じられてきた 早期のを持つ脊椎動物は 歯の非縁のファイルを持っていたという説に 異議を唱えるものである.
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