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オールドビカ紀のトリロビテスの並行した漸進的な進化
1Department of Geology, Trinity College, Dublin, Ireland.
Nature
|December 10, 1987
まとめ
この研究は,トリロビットの漸進的な進化の証拠を提示し,急速な進化的変化の考えに異議を唱える. 化石記録の詳細な分析は,何百万年にもわたる系統内のゆっくりと継続的な変化を明らかにします.
科学分野:
- パレオントロジー・パレオントロジー
- 進化生物学の進化生物学について
背景:
- 高解像度の化石の研究は,進化のパターンを評価するために希少である.
- 漸進主義と中断均衡の区別は,しばしば限られた化石データに依存する.
研究 の 目的:
- 化石記録におけるフィレティック・グラデュアリズムの詳細な証拠を提供すること.
- トリロバイトの化石を用いて,ベンシックマクロ無脊椎動物の進化パターンを調査する.
主な方法:
- ウェールズ中部から約15,000のトリロバイト化石を分析した.
- 300万年の間,ピギディアルの肋骨の数などの種診断の特徴の調査.
主要な成果:
- ピギディアルの肋骨の純増加は,最大8つのトリロバイト系統で観察されました.
- 識別された中間形質と,系統内の一時的な傾向逆転.
- 連続した変動により,分類学的に別々の種に分割することは非現実的であることを示した.
結論:
- この研究は,ベンシックマクロ無脊椎動物におけるフィレティック・グラデュアリズムに関する最初の詳細な証拠の一部を提供する.
- 句読点と静止として段階的な変化の誤った解釈は,伝統的なリンネの分類法の適用から生じることがあります.
- バイノミアル分類法の即時適用は,漸進的な進化パターンの検出を妨げることがあります.
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