最も古くから知られている霊長類の骨格と初期のハプロリン進化
Xijun Ni1, Daniel L Gebo, Marian Dagosto
1Key Laboratory of Vertebrate Evolution and Human Origin, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, 142 Xi Zhi Men Wai Street, Beijing 100044, China. nixijun@ivpp.ac.cn
Nature
|June 7, 2013
まとめ
5500万年前とさかのぼる中国初期のエオセーン期の,ほぼ完全な霊長類の化石骨格は,最も基礎的な知られているタルシアを明らかにしています. この発見は,初期の霊長類の進化と分岐時間を明らかにします.
科学分野:
- パレオントロジー・パレオントロジー
- 霊長類の進化について
- 脊椎動物の古生物学について
背景:
- 初期の霊長類の進化を再構築することは,不完全な化石記録のために困難です.
- 初期の霊長類の古生物学と系統学的関係に関する意見の相違は依然として存在しています.
研究 の 目的:
- 重要な初期の霊長類の化石の発見を報告するために.
- 化石の形態学と系統学的位置を分析する.
主な方法:
- ほぼ完全な,関節のある化石霊長類の骨格の発見と発掘.
- 拡散相コントラストX線シンクロトロンマイクロトモグラフィを用いた詳細な形態学的検査.
- 入手可能な証拠の合計に基づいた系統遺伝分析.
主要な成果:
- 中国・エオセンの初期 (5500万年前) の最も古く,最も完全な化石霊長類の骨格を発見.
- 系統遺伝学的分析により,この化石は,最も基礎的なハプロリン類の霊長類,特に茎のタルシア類であると特定されています.
- この化石は,初期のストレプシリン・ハプロリン分裂の証拠を提供し,タッサー類とアンスロポイド類の差異推定を洗練している.
結論:
- 化石は,ストレプシリン類とハプロリン類の霊長類の間の初期の二分論を支持する.
- それは,タッサー類と人類類の間の分岐時間を制限する.
- これは,初期の霊長類は,おそらく昼間活動,樹生,昆虫食動物であり,現代のピグミー・マウス・レムルとサイズが似ていたという仮説を強めている.
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