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最古の復元可能な四足類であるParmastega aelidaeの形状
Pavel A Beznosov1, Jennifer A Clack2, Ervīns Lukševičs3
1Institute of Geology, Komi Science Centre, Ural Branch of the Russian Academy of Sciences, Syktyvkar, Russia.
Nature
|October 25, 2019
まとめ
ロシアの初期のデボニアン四足動物である パルマステガ・エリーダは 脊椎動物の進化について 新しい洞察を提示しています この化石は 初期の四足類の解剖学と 進化の関係に関する重要なデータを 提供しています
科学分野:
- 古生物学
- 進化生物学
- 脊椎動物 古生物学
背景:
- デボニアン四足類の多様性は増えているが 化石はしばしば断片化している.
- イチオステガやアカントステガのような 重要な化石が 初期の四足類の理解を 支配しています
- 現存する化石は 最古の四足の足跡や断片よりも若い.
研究 の 目的:
- 新しい初期フェメニウス四足類の パーマステガ・エリダを記述する
- 3D素材を使ってP. aelidaeの頭蓋骨と肩帯を再現する.
- P. aelidaeの古生物学と遺伝学的な位置を推測する.
主な方法:
- ロシアの化石素材の説明
- 頭蓋骨と肩帯の再構築
- ベイジアンとパルシモニーに基づく 系統遺伝分析
主要な成果:
- パルマステガ・アエリダ (Parmastega aelidae gen. et sp.) について nov. は,最も初期のファメンニアン (約. 3億7200万年前のことです
- 3D素材で 頭蓋骨と肩帯を再現できた
- P. aelidaeは水中で水面を巡る生活様式を示唆する特徴を示しています.
- 系統遺伝学的分析では,ほとんどの木において,パルマステガは他のすべての四足類の姉妹である.
結論:
- パルマステガ・エリーダは,最も古く,最も基礎的な四足類の1つである.
- この発見により 初期の四足類の進化と多様化に関する理解が深まります
- この発見は水生生物から陸生生物への移行に 重要なデータポイントを提供します
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