恐竜の生理学について. 恐竜におけるメソサーミーの証拠

John M Grady¹, Brian J Enquist², Eva Dettweiler-Robinson³

¹Department of Biology, University of New Mexico, Albuquerque, NM 87131, USA. jgrady@unm.edu.

Science (New York, N.Y.)

|June 14, 2014

まとめ

恐竜は,現代のエンドサームとエクトサームの間の中間代謝率を持っていた可能性が高い. これは単純な二分法に異議を唱え,恐竜の生理学と代謝のより複雑な見解を示唆しています.

科学分野:

パレオントロジー・パレオントロジー
脊椎動物生理学脊椎動物生理学
進化生物学の進化生物学について

背景:

恐竜の代謝戦略 (エクトーミー対エンドーミー) は依然として議論されている.
エンドサーミーの証拠は,化石の骨の分析から推測された急速な成長率に依存する.
以前の研究では,包括的な比較データとエネルギーに関する枠組みが欠けていました.

研究の目的:

比較的アプローチを用いて恐竜の代謝率を調査する.
恐竜の成長と代謝率が理論的予測と一致するかどうかを判断する.
新しいデータに照らして,Endotherm vs. ectothermの分類を再評価する.

主な方法:

主要な恐竜のクラードを含む,現存する脊椎動物と化石脊椎動物のためのコンパイルされたオントジェネティック成長データ.
成長と代謝率を分析するために代謝スケーリングアプローチを適用しました.
体のサイズと環境温度の影響も考慮した.

主要な成果:

恐竜の成長と代謝率は一般的に理論的な予測に従っており,いくつかのグループ偏差があります.
サイズと温度を考慮すると,恐竜の代謝率は,エンドサームとエクトサームの間に中間的であった.
恐竜の代謝率は,現存するメソサーム類の代謝率に最も近い.

結論:

伝統的なエンドサーム/エクサーム二分法は,恐竜の代謝を理解するための過度の単純化である.
恐竜はおそらく,現代のメソサーム類に似た,中間代謝戦略に従事していた.
脊椎動物の代謝多様性についての理解を洗練するためにさらなる研究が必要です.

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