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カンブリア期初期に生息した,放射性歯類のような捕食動物
Han Zeng1,2,3, Fangchen Zhao4,5,6, Kecheng Niu7
1State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing, China.
Nature
|November 5, 2020
まとめ
初期のユーアルトポッドの進化は,ラディオドンタとデウテロポダを結びつけるカンブリア時代の化石であるキリンキア・ザンギによって明らかにされている. この発見は 付属体の進化と 初期の節足類の関係に関する 重要な洞察を示しています
科学分野:
- 古生物学
- 進化生物学
- 系統遺伝学
背景:
- 初期のエウアルトポッドの進化を理解することは,メタゾアンの進化における重要な課題である.
- カンブリア化石は重要なデータを提供しているが,主要なエウアートロポッド群の相互関係については依然として議論されている.
- ラジオドントは,第二の頭部セグメント (Deuteropoda) にほとんど前頭部付属体を持つ,ユアートロポッドに遺伝学的に近いが,ギャップが存在する.
研究 の 目的:
- カンブリア初期チェンジャング生物の新型エウアルトポッドの化石である キリンキア・ザンギについて説明します
- キリンキシアの系統的位置と,早期のエウアルトポッドの進化への影響を再構築する.
- 初期の足類の進化的変異とホモロジーを研究する.
主な方法:
- 特別に保存された標本に基づいた新しい化石種,キリンシア・ザンギの記述.
- キリンキシアと他の関連するカンブリア時代と現存する分類を組み込んだ系統再構築.
- 前肢と他の重要な特徴を比較した形状分析
主要な成果:
- キリンキア・ザンギは,複数の目と猛禽類の前部付属体を含む,ラディオドンタとデュテロポダの両方の特徴を示しています.
- 系統遺伝学的分析では,キリンキアがラジオドンタとデウテロポダの間の移行分類である.
- この研究は,ラジオドントとメガチェイランの正面付属体のホモロジーを支持し,祖先のラプトリアルの形態からチェリセラとアンテナの起源を示唆しています.
結論:
- Kylinxiaは初期のエウアートロポッドの遺伝関係に関する重要な洞察を提供している.
- 進化の変容と前肢の差異を明らかにしています
- この発見は,エウアートロポッドにおける重要な進化的革新の起源を理解するのに役立ちます.
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