コメント "超構造は,ユナノゾウの祖先の脊椎動物の喉骨格を明らかにする"
Kaiyue He1, Jianni Liu1, Jian Han1
1Shaanxi Key Laboratory of Early Life and Environments, State Key Laboratory of Continental Dynamics, Department of Geology, Northwest University (NWU), Xi'an 710069, P. R. China.
Science (New York, N.Y.)
|July 27, 2023
まとめ
ユナノゾウは幹群の脊椎動物ではない. 8千以上の標本における超構造と形態学的分析は 脊椎動物の主要な特徴の存在を否定し,以前の系統遺伝学的な提案に異議を唱える.
科学分野:
- 古生物学
- 発達生物学
- 進化生物学
背景:
- 以前の研究では,特定の解剖学的特徴に基づいて,幹群の脊椎動物としてユナノゾウを提案しました.
- これらの特徴には,細胞軟骨,フィブリリンマイクロファイバー,および枝状の弓の下帯状の棒が含まれています.
研究 の 目的:
- ユナノゾウの遺伝的位置を再評価する
- 脊椎動物の親和性を確認または反証するために,ユナノゾウの超構造と形態を調査する.
主な方法:
- ユナノゾアンの詳細な超構造分析
- 8千以上のユナノゾアの標本を 徹底的に分析した
- 既知の脊椎動物と無脊椎動物との比較分析
主要な成果:
- ユナノゾアの細胞軟骨の欠如が確認されました
- フィブリリンマイクロファイバーがないことが示された.
- 帯状下棒の構造は脊椎動物の構造と同型ではないことが判明した.
- 形質学的および超構造的証拠は脊椎動物の親和性を支持しない.
結論:
- ユナノゾウは幹群の脊椎動物ではない.
- 以前に提案された遺伝子分類は,新しい証拠に基づいて拒否されます.
- メタゾア内のユナノゾアの正確な遺伝的位置を決定するには,さらなる研究が必要である.
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