発達中の鳥の骨盤は 恐竜の祖先の条件を通過します
Christopher T Griffin1,2,3, João F Botelho1,2,4, Michael Hanson1,2
1Department of Earth and Planetary Sciences, Yale University, New Haven, CT, USA.
Nature
|July 27, 2022
まとめ
鳥の骨盤の発達は 祖先の恐竜の特徴を明らかにし 胚の成長中に一時的に現れる この進化パターンは 鳥類の進化における"終端加算"のメカニズムを示唆している.
科学分野:
- 古生物学
- 発達生物学
- 進化生物学
背景:
- 生きている鳥 (Aves) は,爬虫類の祖先から重要な解剖学的改変を示しています.
- 鳥の骨盤は 初期のアーコサウルスから現代の鳥への移行の間に 大きく変化した.
- 化石記録は進化的変化を記録しているが,その基礎となる発達過程 (オントジェニー) はあまり理解されていない.
研究 の 目的:
- 胚性画像を用いて鳥の骨盤組織の3次元形態変異を調査する.
- 鳥の骨盤の発達を 恐竜から鳥への移行の化石記録と 比較するためです
- 鳥の骨盤の進化の基礎を理解する
主な方法:
- 骨盤組織の発達を3次元で調べた
- 鳥の骨盤のオントゲニーと系統遺伝子の比較をするために定量分析を行った.
- アーコサウリアの骨盤内の表型共変性を調査した.
主要な成果:
- 祖先の恐竜の骨盤の特徴 (例えば,前向きの陰茎,陰茎の"ブーツ") は,初期の鳥の胚形成の間に一時的に観察される.
- 鳥の骨盤の発達は 鳥以外の恐竜から 進化的に獲得された特性を反映した 産前配列に従っている.
- 骨盤における表型共変性,アーコサウリア全体に保存され,祖先状態の保持を潜在的に説明する.
結論:
- 鳥の骨盤の進化は"末端の付加"によって起こり,新しい特徴が発達順序の終わりに追加され,以前の先祖状態を表現する.
- 骨盤におけるフェノタイプの統合は,進化の過程で端末添加のための新しいメカニズムを示唆しています.
- この研究は,進化的移行と祖先の特徴の保持を理解するために胚の発達を研究することの重要性を強調しています.
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