ティラノサウルスは速いランナーではなかった

John R Hutchinson¹, Mariano Garcia

¹Department of Integrative Biology, University of California, Berkeley, California 94720-3140, USA. jrhutch@stanford.edu

Nature

|March 5, 2002

まとめ

ティラノサウルスのような大型の肉食恐竜は,おそらく速く走ることができなかった. ランニングに必要な筋肉質の推定は,彼らの巨大なサイズが彼らの速度を制限することを示唆しています.

科学分野:

パレオントロジー・パレオントロジー
バイオメカニクスバイオメカニクス
恐竜の移動方法恐竜の移動方法

背景:

ティラノサウルスを含む大型のセロポッド恐竜の最大速度と歩行は,依然として議論の余地があります.
以前の研究では,歩行だけでできる速度から20m/sを超える速度まで推薦されていた.

研究の目的:

恐竜の走行能力を推定するためのバイオメカニカルモデルを開発および検証.
大型のセロポッドの高速移動に必要な筋肉質を測定するために.

主な方法:

速く走るのに必要な最小の伸縮筋質量を推定するモデルを開発した.
既存のワニやニワトリのデータを用いて検証されたモデル予測.
このモデルを,ティラノサウルスを含む様々な絶滅した恐竜種に適用した.

主要な成果:

このモデルは,現代の動物の走行能力を成功裏に予測しました.
より小さな恐竜は,潜在的に走行能力があることが判明しました.
計算によると,成人のティラノサウルスは,高速に走るには信じられないほど大きな筋肉を必要としていた.

結論:

バイオメカニカルモデルは,非常に大きな恐竜 (約. 6,000kg) は走る能力がなかった可能性が低い.
ティラノサウルスや同様の巨大セロポッドは,質量の制約により,ゆっくりとした歩行に限定されていた可能性が高い.

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