パレオントロジー. ストラッチ型恐竜のノック
M A Norell1, P J Makovicky, P J Currie
1American Museum of Natural History, Central Park West at 79th Street, New York, New York 10024-5192, USA. norell@amnh.org
Nature
|August 31, 2001
まとめ
新しい化石の発見は,初期のオルニトミミド恐竜は,歯のある祖先とは異なり,大きな獲物を狩るためではなく,水中の環境でフィルター餌のために歯のないノックを使用した可能性があることを明らかにしています.
科学分野:
- パレオントロジー・パレオントロジー
- 脊椎動物学 脊椎動物学
- メソゾイク時代の生態系
背景:
- オーニソミミミッドは,白亜紀のセロポッド恐竜の多様なグループである.
- 原始的なオルニトミミッドは歯を持ち,その派生形態は歯のないノックを進化させた.
- 派生オルニトミミドにおける歯のないの機能は,その食生活に関する議論の対象となっている.
研究 の 目的:
- の軟組織構造の分析を通じて,派生オルニトミミドの食習慣を調査する.
- これらの特殊な恐竜の古生態学と栄養戦略に関する新しい洞察を提供するために.
主な方法:
- 新たに発見された2つのオルニトミミド標本の記述.
- これらの標本のノック内の保存された軟組織構造の分析.
主要な成果:
- 研究されたオルニソミミミドのくちばしには,フィルターで栄養を供給するメカニズムと一致する特徴があります.
- 証拠によると,これらの恐竜は水中環境で餌を獲り,堆積物から餌を汲み取っていた.
- この発見は,以前,いくつかのオルニトミミドについて仮説を立てていた捕食性の餌戦略からの逸脱を示している.
結論:
- 派生したオルニソミミミドは,水生生息地での特殊なフィルター餌のために彼らのノックを使用した可能性が高い.
- この適応は,オルニソミミド系における重要な食生活の変化を表しています.
- この研究は,白亜期における恐竜の栄養の多様性についての理解を深める.
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