最古の完全なの脊椎動物は,中国のシルル紀初期から
You-An Zhu1,2, Qiang Li3,4, Jing Lu1,2,5
1Key CAS Laboratory of Vertebrate Evolution and Human Origins, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences (CAS), Beijing, China.
Nature
|September 28, 2022
まとめ
南中国から新たに発見された化石は 初期シルア紀の 多様で保存状態の良い 魚を明らかにしています これらの発見は,の脊椎動物の初期の進化と多様化に関する重要な洞察を提供します.
科学分野:
- 古生物学
- 進化生物学
- 脊椎動物学
背景:
- 分子研究により,の脊椎動物はオルドヴィチア後期 (約. 450万年前から存在していた.
- 前回の最古の完全な魚化石は,シルウリア紀後期 (約1万年) に遡る. 425万年前
- 化石記録のギャップは のある脊椎動物の最古の歴史を 隠していたのです
研究 の 目的:
- 新規のコンサーヴァット・ラガーステッテの調査を報告する. 多様で保存状態の良い 初期のシルウア紀の魚を採取する.
- 詳細な全身形態の洞察を早期の椎動物に提供する.
- 爪のある脊椎動物の 今まで見たことのない多様性を明らかにするために
主な方法:
- 中国南部の重慶にあるコンサーヴァト・ラガーステートの発見と発掘.
- 新しく発見された完全な魚の化石の 詳細な形態学的分析
- プラコダームとコンドリキシアン化石の記録との比較分析
主要な成果:
- 初期シルウリア (テリヒア紀,約. 436万年前から存在していた.
- "Xiushanosteus mirabilis"属と属種の説明 変形した頭蓋骨の特徴がある.
- シェナカントス・ヴェルミフォーミス (Shenacanthus vermiformis) 属と属種の説明 独特の胸部装甲を持つコンドリヒシアンです
結論:
- 新しい化石は,初期シルウリアン期におけるの脊椎動物の大幅な多様化を示している.
- プラコデルマとオステイチアンの頭蓋骨を橋渡しする.
- *Shenacanthus vermiformis*は コンドリヒチアンの新型のの特徴を示し,より大きな形態的差異を示唆しています.
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