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ペンギン羽の形状と色が進化した証拠は化石から得られた
Julia A Clarke1, Daniel T Ksepka, Rodolfo Salas-Gismondi
1Department of Geological Sciences, University of Texas at Austin, Austin, TX 78712, USA. julia_clarke@jsg.utexas.edu
まとめ
ペンギンの化石の羽は,主要な羽毛の特徴の初期の進化を明らかにしています. 現代のペンギンの羽毛の色は後に進化し,古代の灰色と赤茶色の色彩と異なる.
科学分野:
- パレオントロジー・パレオントロジー
- 進化生物学の進化生物学について
- 鳥類の解剖学について
背景:
- ペンギンの羽は,水生生物に対するユニークな適応を示しています.
- ペンギンの羽毛の形状と色彩の進化史は,化石の証拠が不足しているため,まだ十分に理解されていない.
研究 の 目的:
- ペンギンの羽の構造と色合いの初期の進化を調査する.
- 化石の羽根を基に古代ペンギンの外観を再現する.
主な方法:
- ペルーのエオセンの末期の巨大ペンギン化石の分析.
- 化石化したメラノソームの顕微鏡検査により,羽毛の色を決定する.
- 化石の羽の構造と,現存するペンギンの羽の比較.
主要な成果:
- 化石は,未分類の主要な翼の羽と,広い体のコントールの羽根軸を含む,早期に進化した羽毛の特徴を展示しています.
- 化石化したメラノソームは,古代のペンギンの羽は灰色と赤茶色で,他の鳥と似ていることを示唆しています.
- 現存するペンギン羽には,大きな円形メラノソームがあり,その深黒茶色の色は,後の進化の発展である.
結論:
- 水中飛行のためのペンギン羽の主要なマクロ構造的修正は,その系統の初期に進化した.
- ペンギン羽のナノ構造と色彩は,飛行のための羽の形状の初期進化後に大幅に修正されました.
関連する概念動画
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