まとめ
化石骨の酸素同位体組成は,体温を明らかにする. ティラノサウルス・レックスは,体温が安定した状態を維持していた可能性があり,これはエンドサーミックな特徴を示唆している.
科学分野:
- パレオントロジー・パレオントロジー
- バイオジオケミストリー バイオジオケミストリー
- パレオサーモメトリー (旧熱測定法)
背景:
- 脊椎動物の骨リン酸塩 (delta(p)) の酸素同位体組成は,骨形成中に摂取した水と体温を反映しています.
- 骨リン酸塩の酸素同位体は,体水と均衡状態にあり,体全体で生理的に安定しています.
研究 の 目的:
- よく保存された化石の脊椎動物における骨内温度変化と骨間温度差を測定する.
- ティラノサウルスの体温調節と代謝率を評価する.
主な方法:
- 化石の脊椎動物の骨のリン酸における酸素同位体組成 (デルタp) の分析.
- デルタ (p) 変数を用いて,骨内および骨間における温度変動を推論する.
主要な成果:
- ティラノサウルス・レックス化石から得られた酸素同位体データは,体温の変動が4°C未満であることを示している.
- この安定した体温は,ティラノサウルスのホメオサーミーを示唆している.
結論:
- ティラノサウルスのホメオサーミーは,現代のエンドサームと比較できる比較的高い代謝率を意味します.
- 骨のリン酸塩の酸素同位体分析は,絶滅した脊椎動物の熱調節を再構築するための有効な方法です.
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