まとめ
世界最古の化石は,ブラジルのプリスティグアナ・ブラシリエンシス (Pristiguana brasiliensis) です.
科学分野:
- 古生物学と進化生物学で,スクワマタ爬虫類を中心に研究しています.
背景:
- イグアニダ (イグアナ) の化石記録は,南米では稀です.
- 以前の理論では,イグアニドの起源が北米にあると考えられていた.
研究 の 目的:
- 化石トカゲの新しい属と種であるPristiguana brasiliensisを記述する.
- 初期のイグアニidaeの系統的位置と生物地理的起源を決定する.
主な方法:
- 新しい化石トカゲの標本の記述と系統遺伝分析.
- 比較形質は,現存するおよび絶滅したイグアニドおよびテイドトカゲと比較した.
主要な成果:
- Pristiguana brasiliensisは,上白亜紀に遡る,最も古くから知られているイグアヌードイの化石を表しています.
- この化石には,イグアヌア科と,その親類であるテイア科の特徴が表れています.
- イグアニドの化石は,北米では,ずっと後,エオセンの初期に現れた.
結論:
- Pristiguana brasiliensisの発見は,Iguanidae.ファミリーの南アメリカの起源を支持しています.
- イグアニドのゴンドワナ起源は,以前に提案された北部の起源よりも妥当性があります.
- この発見は,の進化と分散を理解する上で重要な意味を持つ.
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