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Updated: Jul 8, 2026

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Initiating Differentiation in Immortalized Multipotent Otic Progenitor Cells
Published on: January 2, 2016
モノトレムとテリアンの中耳骨の独立した起源
Thomas H Rich1, James A Hopson, Anne M Musser
1Museum Victoria, Post Office Box 666E, Melbourne, Victoria 3001, Australia. trich@museum.vic.gov.au
まとめ
最も古いモノトレム化石であるTeinolophos trusleriは,哺乳類の中耳骨を形成するために脱落したアクセサリー骨を示唆するの構造を示している. これは,哺乳類の中耳がモノトリームとテリアンで独立して進化したことを示している.
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
- 比較解剖学 比較解剖学とは
背景:
- 哺乳類の中耳骨 (マレウス,インカス,ステープス) は,骨から進化した.
- 哺乳類の中耳の進化の経路は,特にモノトリームについて議論されています.
研究 の 目的:
- 初期の白亜紀のモノトレムTeinolophos trusleriのの形態を調査するために.
- 哺乳類の中耳骨の進化的起源をベースアルモノトレームで推論する.
主な方法:
- Teinolophos trusleri.の歯骨の分析について
- 哺乳類のアウトグループと現存する哺乳類を比較した解剖学的研究.
主要な成果:
- テイノロフォス・トラスレリ (Teinolophos trusleri) は下の谷部を持ち,付属の骨 (角形,冠状,) の側面がある.
- 証拠によると,角骨と関節骨/前関節骨は,この基礎モノトレームで下に付着していた.
- これらの骨は,それぞれ哺乳類のエクトートンパニックとマレウスに同型です.
結論:
- 哺乳類の決定的な中耳の構造は,モノトレームとテリアンで独立して進化した.
- この発見は,異なる系統における重要な哺乳類の特徴の独立した進化を明らかにしている.
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