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中国のトライアス紀下期に生息していた,短口の基礎型イチオサウル形
Ryosuke Motani1, Da-Yong Jiang2, Guan-Bao Chen3
1Department of Earth and Planetary Sciences, University of California, Davis, One Shields Avenue, Davis, California 95616, USA.
Nature
|November 11, 2014
まとめ
中国から新たに発見された爬虫類の化石は,両生類の習慣を示唆し,イチオプテリギア (Ichthyopterygia) と呼ばれる海洋爬虫類の起源のギャップを埋める可能性がある. この発見は,初期の海洋脊椎動物の進化に光を当てています.
科学分野:
- パレオントロジー・パレオントロジー
- 脊椎動物の進化について
- 海洋爬虫類の起源について
背景:
- 化石記録の不完全さは,多くの脊椎動物群の進化的起源を曖昧にしています.
- イチオプテリギア (Ichthyopterygia) は,海洋爬虫類の強制性であり, トライアス紀初期に,既知の移行形態なしに現れた.
研究 の 目的:
- 中国のトライアシク初期からの基礎的なイチオサウリフォーム化石を記述する.
- 初期のイクチオサウリフォームの進化的関係と古生物学を調査する.
主な方法:
- 化石の発見と発掘.
- 新しい種の骨格分析.
- 進化的関係を決定するための系統遺伝分析.
主要な成果:
- 基本的なイチオサウリフォームの記述,原始的な特徴で,両生類の習慣と限られた陸上移動を示唆しています.
- この基礎形態の吸食の識別,派生イチオサウリフォームと対比する.
- イチオサウル形類とヒュペシュキアの姉妹群の関係を支持し,イチオサウロモルファを形成する.
結論:
- この新しい種は,イチオプテリジアンの初期の進化と潜在的な両生類の起源についての洞察を提供します.
- この発見は,イクチオサウロモルファがトライアシク初期に南中国の熱帯群島に起源を持つことを示唆している.
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