カルシート骨格を持つ化石のペアリングしたの裂け目
Patrício Dominguez1, Antone G Jacobson, Richard P S Jefferies
1Department of Palaeontology, The Natural History Museum, Cromwell Road, London SW7 5BD, UK.
Nature
|June 21, 2002
まとめ
化石のエチノデルマであるJaekelocarpus oklahomensisは,以前は半径対称性が欠けると考えられていたが,内部にの裂け目があった. この発見は,初期のデュテロストームの進化と骨格の発達に関する私たちの理解を洗練します.
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
- 比較解剖学 比較解剖学とは
背景:
- デウテロストミア (Deuterostomia) は,帯状動物,半帯状動物,皮動物で構成され,確立されたモノフィレティック群である.
- エキノダームは通常,放射性対称性を表し,カルシート骨格を持っているが,化石形態は時に放射性対称性が欠けている.
- 上炭鉱期の化石であるJaekelocarpus oklahomensisは,外見上ほぼ双方向対称であり,伝統的にミトラタ群の中に置かれている.
研究 の 目的:
- Jaekelocarpus oklahomensisの内部解剖学と機能的形態論を調査する.
- デュテロストミア族内のジャケロカルプス・オクラホメンシスの系統遺伝的位置を明確にするために.
主な方法:
- コンピューターのX線マイクロトモグラフィーを用いて,ジャケロカルパス・オクラホメンシスの詳細な解剖を調査した.
- 機能的解剖学は,詳細な解剖学的データに基づいて解釈されました.
主要な成果:
- Jaekelocarpus oklahomensisの詳細な内部解剖学が明らかにされ,以前の記述を上回りました.
- Jaekelocarpus oklahomensis.の内部でペアリングされたのスリートの証拠が特定されました.
- Jaekelocarpus oklahomensisの機能的解剖学が解釈されました.
結論:
- Jaekelocarpus oklahomensisは,外側の双方向対称性にもかかわらず,内部にの裂け目があり,従来の分類に異議を唱えた.
- この発見は,Deuterostomia内のJaekelocarpus oklahomensisの改訂された系統遺伝的位置を示唆しています.
- この研究は,初期のデウテロストームにおける骨格構造と対称性の多様性と進化を理解するのに寄与します.
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