ジュラスのサウロポッド恐竜の2匹の首の姿勢と食生活
1Computer and Information Science, University of Oregon, Eugene, OR 97403, USA. Biological Sciences, Northern Illinois University, DeKalb, IL 60115, USA.
Science (New York, N.Y.)
|April 30, 1999
まとめ
デジタル再構築では,DiplodocusとApatosaurusの首は考えられていたより柔軟性が低いことが示され,地面レベルで餌を与えることを示唆しています. これらの長い首の恐竜は,おそらく高いのではなく,低いところに,以前の仮定に異議を唱えた.
科学分野:
- パレオントロジー・パレオントロジー
- バイオメカニクス バイオメカニクス
- 脊椎動物学 脊椎動物学
背景:
- サロポッド恐竜,特にディプロドコスやアパトサウルスのようなディプロドキッドは,非常に長い首を持っていた.
- 以前の仮説では,これらの長い首は,高い植生地に到達し,高いブラウジングを容易にしたと示唆されていました.
- サロポッドの首の生体力学と機能的形態学は,現在も進行中の研究と議論の対象となっている.
研究 の 目的:
- ディプロドックスとアパトサウルスの頸椎をデジタルで再構築する.
- ネックスの中立姿勢と運動範囲 (餌の範囲) を決定する.
- 再構築された子宮頸部の姿勢と柔軟性に基づいて栄養戦略を推論する.
主な方法:
- 2つのディプロドキド種の頸椎柱の関節化されたデジタル再構築.
- 中立で歪みのない首の姿勢と,体に対する頭部位置の分析.
- 首の柔軟性の評価,横側および背側 (上向き) の曲線能力を含む.
主要な成果:
- DiplodocusとApatosaurusの両方の中立の首の姿勢は,ほぼ直線で,下に向かって穏やかに低下していました.
- 頭は,首と頭の角度による中立姿勢で地面に近い位置に置かれました.
- 首の柔軟性は,慣例的に描かれているよりも少ない;Diplodocusは,アパトサウルスよりも横側と背中の移動性が少ないことを示しました.
結論:
- 再構築された子宮頸部の姿勢と限られた柔軟性は,地上給食または低ブラウジングに適応することを示唆しています.
- これらの発見は, diplodocid サウロポッドが高度なブラウザーであるという伝統的な見解に異議を唱える.
- この研究は,大型の草食恐竜の生態学的役割と食生活に関する新しい洞察を提供している.
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