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Dissection and Flat-mounting of the Threespine Stickleback Branchial Skeleton
Published on: May 7, 2016
最初の頭蓋骨は,初期エオセンの霊長類のShoshonius cooperiと,人類型-タルシア類の二分法である
K C Beard1, L Krishtalka, R K Stucky
1Section of Vertebrate Paleontology, Carnegie Museum of Natural History, Pittsburgh, Pennsylvania 15213.
Nature
|January 3, 1991
まとめ
化石の霊長類の頭蓋骨は,Shoshonius cooperiがTarsiusと密接に関連していることを明らかにし,霊長類の進化と人類類の起源に関する以前の考えに挑戦しています. この発見は,これまで理解されていたよりも,タルシア類と人類類の間の早めの分岐を示唆している.
科学分野:
- 類人猿の古生物学について
- 進化生物学の進化生物学について
- 比較解剖学 比較解剖学とは
背景:
- タルシア類と絶滅したオモマイド類の霊長類の系統遺伝的配置は,霊長類の進化,特に人類類の起源を理解するために重要である.
- 現存する仮説によると,タルシアはオモマイド,アンスロポイド,またはストライプシリンと関連している.
研究 の 目的:
- 新しい頭蓋骨素材を用いて,初期のオモミド類霊長類の系統遺伝関係を調査する.
- 類人猿の中でタルシアの進化的位置に関する競合する仮説を検証する.
主な方法:
- 初期エオセンの4つのショショニウス・クーペリ頭蓋骨の頭蓋骨解剖学の分析.
- 既知のオモミードやタルシア類の化石,現存する分類と比較的な系統遺伝分析.
主要な成果:
- Shoshonius cooperiの頭蓋骨の解剖学は,タルシウスとの共通の祖先が,人類類や他の知られているエオセンのオモミイドよりも近いことを示しています.
- この系統遺伝的位置は,霊長類のサブオーダーであるハポロヒニがモノフィレティックである場合,アントロポイドとタルシウスは初期エオセンの時点で分岐したことを示唆しています.
結論:
- Shoshonius cooperiは,初期の霊長類の進化と主要な霊長類群の分岐に関する重要な洞察を提供します.
- この発見は,霊長類の系統学的見直しを必要とし,人類類とタッサー類の分裂を化石記録のはるかに早い時期に位置づけている.
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