ヨーロッパから来たクレタケイア期後半のセラトプシアン恐竜で,アジア的な親和関係がある
Attila Osi1, Richard J Butler, David B Weishampel
1Hungarian Academy of Sciences, Hungarian Natural History Museum, Research Group for Paleontology, Ludovika tér 2, Budapest 1083, Hungary. hungaros@freemail.hu
Nature
|May 28, 2010
まとめ
ハンガリーから発見された新しい角の恐竜の化石は,セラトプシアン (角の恐竜) がクレタ紀後半のヨーロッパに住んでいたことを明らかにしています. この発見は,恐竜の分布と移動パターンに関する以前の考え方に挑戦しています.
科学分野:
- パレオントロジー・パレオントロジー
- 恐竜の進化について
- バイオジオグラフィー バイオジオグラフィー
背景:
- セラトプシアン (角のある恐竜) は,白亜紀期には多様で豊富でした.
- 彼らの地理的分布は,以前はアジアと北米に限られていると考えられていた.
研究 の 目的:
- ハンガリーから採取した,新しいセラトプシアの頭蓋骨素材を記述する.
- 欧州の白紀後期恐竜の生物地理的仮説を再評価する.
主な方法:
- 化石の頭蓋骨素材の記述.
- 既知のセラトプシアン分類との比較分析.
- 恐竜の分布に関する生物地理学的分析.
主要な成果:
- アジャケラトプス・コズマイ (Ajkaceratops kozmai) の発見,ウングリアのクレタ紀末期のコロナサウルスのセラトプシアン.
- アジカセラトプスはアジアの"バガセラトプシド"に類似している.
- クレタ紀後期ヨーロッパにおけるセラトプシアンの存在を示し,複数の分散イベントを示唆しています.
結論:
- セラトプシオンはクレタセア紀末期のヨーロッパを占領し,以前の生物地理学的モデルに異議を唱えた.
- アジャケラトプスの存在は,西のテシアン諸島群に"島から島へ移動する"分散を示唆している.
- 欧州の恐竜ファウナの構成は,再評価が必要である.
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