プロトメリシオンは初期のダシクラド藻であり,カンブリア紀のブリオゾーンではない
Jie Yang1, Tian Lan2, Xi-Guang Zhang3
1Institute of Palaeontology, Yunnan University, Chenggong, Kunming, China.
Nature
|March 8, 2023
まとめ
初期のカンブリア動物化石は,以前はモス動物族 (Bryozoa) と考えられていたが,現在は緑藻として知られている. この再分類により,カンブリア時代のブリオゾアは未発見のままである.
科学分野:
- 古生物学
- 進化生物学
- 海洋生物学
背景:
- 動物の系統と体型は 5億年以上前のカンブリア爆発で発生した.
- ブリオゾア属 (モス動物) は,彼らの骨格を区別する難しさのために,明確なカンブリア化石の証拠が欠けている.
- 初期のブリオゾアンの最強の候補として,フォスファート微生物であるプロトメリシオンが考えられた.
研究 の 目的:
- プロトメリシオン化石の分類を再評価する
- 初期のカンブリアのコミュニティにおける ブリオゾア体の起源を調査する.
主な方法:
- プロトメリシオン類のマクロ化石の例外的に保存された非鉱化解剖学的分析.
- 骨格構造の詳細な検査
- 化石化過程を理解するためのタフォノミクス分析
主要な成果:
- プロトメリシオン化石は,ブリオゾアと一致しない非鉱物化した解剖学を示している.
- 骨格の特徴と"ゾオイドの開口"は藻類の構造として再解釈されます.
- プロトメリシオンは,知られている最も古いダシクラデリアン緑藻である.
結論:
- プロトメリシオンは 初期のブリオゾーンではなく 初期のベンティック光合成体を表しています
- ブリオゾア体の起源はカンブリア時代から不明である.
- カンブリア紀の 明確なブリゾオンは まだ発見されていない.
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