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ドイツのエオセンのトカゲは,アンフィスベニアの起源を明らかにしています
Johannes Müller1, Christy A Hipsley, Jason J Head
1Museum für Naturkunde, Leibniz-Institut für Evolutions- und Biodiversitätsforschung an der Humboldt-Universität zu Berlin, Invalidenstr. 43, 10115 Berlin, Germany.
Nature
|May 20, 2011
まとめ
化石のトカゲの発見は,ラセルチドとアンフィスベニアの間の関連性を支持し,穴掘りは四肢の喪失の前に進化したことを示唆しています. この発見は,化石 (掘る) ワニの進化的起源を明らかにします.
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
- 脊椎動物学 脊椎動物学
背景:
- アンフィスベニア (虫) は,議論の余地のある進化的起源を持つ化石である.
- 分子データは,ラセルチド類との親和性を示唆しているが,形態学では蛇と結びついている.
- 以前,アンフィスベニア人の起源に関する化石の証拠は,信頼性がありませんでした.
研究 の 目的:
- アンフィスベニア人の系統的関係と祖先の生態学を調査する.
- アンフィスベニア起源に関する競合する仮説をテストする最初の化石ベースの証拠を提供すること.
- アンフィスベニアの化石化に至る進化のステップを解明する.
主な方法:
- ドイツのメッセルから発見された新しいエオセンのトカゲの化石の発見と記述.
- 頭蓋骨と頭蓋骨後の解剖学の比較形態学的分析.
- スクワメットの体型と推論された生態学の形態測定分析.
主要な成果:
- 新しい化石は,強化されたアキネティックな頭蓋骨と脳蓋骨を含むラセリドのような特徴を示しています.
- この形態学は,ラセリド-アンフィスベニアン単一体を支持する最初の証拠を提供します.
- 後頭蓋骨の解剖学は,好機的な掘削を示唆し,頭蓋骨の強化は,頭先掘削の初期の進化を示唆しています.
結論:
- この発見は,アンフィスベニアやヘビにおける無肢の独立した進化を裏付けている.
- 首を先に掘ることは,アンフィスベニアの進化において,体長が大きく伸びる前に起こった可能性が高い.
- この化石は,アンフィスベニアンの初期の生態学的適応に関する重要な洞察を提供します.
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