プロザオロポッド恐竜の生命史における発達的な可塑性
P Martin Sander1, Nicole Klein
1Institut für Paläontologie, Universität Bonn, Nussallee 8, D-53115 Bonn, Germany. martin.sander@uni-bonn.de
まとめ
初期の恐竜であるプラテオサウルス・エンゲルハーディ (Plateosaurus engelhardti) は,爬虫類に似た環境要因の影響を受けた成長とともに,多様な生命の歴史を示した. ヒストロジーは,この一般的なプロザオロポッドの成長マークと体サイズとの間の矛盾した相関を明らかにしました.
科学分野:
- パレオントロジー・パレオントロジー
- 脊椎動物生物学 脊椎動物生物学
- メソゾイク時代の生態系
背景:
- プラテオサウルス・エンゲルハーディ (Plateosaurus engelhardti) のようなプロザウロポッド恐竜は,最も初期の恐竜群の1つであった.
- 恐竜の生命の歴史を理解することは,過去の生態系と進化の動態を再構築するために不可欠です.
- 化石化した骨の組織学的分析は,個々の成長パターンと生命史戦略の洞察を提供します.
研究 の 目的:
- 初期のプロザオロポッド恐竜プラテオサウルス (Plateosaurus engelhardti) の生命史の変動性を調査する.
- プラテオサウルスの骨組織学,成長率,体サイズとの関係を決定する.
- プラテオサウルスの生命史の可塑性を,現代の爬虫類,哺乳類,鳥類,その他の恐竜と比較するために.
主な方法:
- Plateosaurus engelhardtiの化石の長骨組織学的分析について.
- 成長速度を評価するために,繊維細細骨の骨構造の検査.
- 成長パターンを推測するために,成長マーク (例えば,LAG) の質的および定量的分析.
- 組織学的特徴と推定体のサイズとの相関分析.
主要な成果:
- プラテオサウルスは,恐竜の特徴である急速な成長率を示しており,その証拠は,繊毛細骨である.
- 成長停止とマークカウントを含む組織学的特徴は,体サイズと相関性が悪いことを示しました.
- プラテオサウルスの個々の生歴は,環境要因によって大きく影響を受けた.
- 生命の歴史に対するこの環境の影響は,現代の熱中性爬虫類に見られるものと並行しています.
結論:
- Plateosaurus engelhardtiは,単純なサイズ-成長関係から逸脱して,変動する生命の歴史を持っていた.
- 環境要因は,プラテオサウルスのオントゲニスを形成する上で重要な役割を果たしました.
- プラテオサウルスの生命史の可塑性は,内熱性の哺乳類,鳥類,または他の恐竜ではなく,外熱性の爬虫類と一致しています.
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