ジュラ紀の哺乳類形態と,最も初期の哺乳類の進化的適応
Chang-Fu Zhou1, Shaoyuan Wu, Thomas Martin
1Paleontological Museum of Liaoning, Shenyang Normal University, Shenyang, Liaoning 110034, China.
Nature
|August 9, 2013
まとめ
新しいジュラ紀中期の化石は,皇冠哺乳類より前の哺乳類の初期の草食性を明らかにしています. この発見は,現代の哺乳類が進化する前に,特殊な歯や毛皮のような哺乳類の特徴の起源を強調しています.
科学分野:
- パレオントロジー・パレオントロジー
- 進化生物学の進化生物学について
- 哺乳類の進化について
背景:
- 哺乳類の特徴は,トライアス紀とジュラ紀の間,絶滅した哺乳類の形態に由来しています.
- 初期の哺乳類の進化を理解することは,哺乳類の起源についての洞察を提供します.
研究 の 目的:
- 哺乳類の重要な特徴を示す新しいジュラ紀中期の化石を記述する.
- 草食動物や他の哺乳類の特徴の進化のタイムラインを調査する.
主な方法:
- 化石の記述と解剖学的特徴の分析.
- 既知の哺乳類形態と現存する哺乳類との比較分析.
主要な成果:
- 新しい化石には下の中耳,移行椎,原始的な足首の特徴があります.
- 高度に派生した歯茎は,特殊な植物のを暗示し,哺乳類の初期の草食性を示唆する.
- 歯の特徴は,以前は孤立した歯からしか知られていなかったエレウテルドンチド群と一致しています.
- 陸上の移動と毛皮の証拠は,哺乳類のは,現在存在する哺乳類の共通の祖先より前のものであることを示唆しています.
結論:
- 草食動物は,皇冠哺乳類の出現前に哺乳類の形態に進化した.
- この発見は,エレウテルドンチドの多様性と生態学についての理解を広げています.
- 特殊な歯とを含む哺乳類の重要な特徴は,進化史のずっと早い時期に発生した.
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