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Using Phylogenetic Analysis to Investigate Eukaryotic Gene Origin
Published on: August 14, 2018
エンドミックなアフリカの哺乳類は,系統樹を揺さぶる
M S Springer1, G C Cleven, O Madsen
1Department of Biology, University of California, Riverside 92521, USA. mark.springer@ucr.edu
Nature
|July 3, 1997
まとめ
この研究は,哺乳類の進化的関係を再定義し,昆虫食者は統一された集団ではないことを示しています. ゴールデンモールは,ゾウのようなアフリカの哺乳類と関連しており,早期の多様な放射線イベントを示唆しています.
科学分野:
- 哺乳類の進化について
- 分子系遺伝学 分子系遺伝学
- 比較ゲノミクスとは
背景:
- 昆虫類 (Insectivora) 序列は歴史的に原始的と考えられており,早期の胎盤哺乳類の進化についての洞察を提供している.
- 以前の解剖学およびクラディスティックの研究では,昆虫食動物は派生的な特徴を有し,その原始的な地位に挑戦することを示唆しました.
- 昆虫類の関係を理解することは,より高いレベルの哺乳類の系統を再構築するために重要です.
研究 の 目的:
- 分子データを用いて,胎盤哺乳類内の昆虫食者の系統的位置を調査する.
- 生きている昆虫食者がモノフィレティック群を形成するかどうかを判断する.
- アフリカの哺乳類の進化的起源と多様化を明らかにする.
主な方法:
- 3つのミトコンドリア遺伝子と2つの核遺伝子のDNA配列の分析.
- 進化的関係を再構築するための系統遺伝分析.
- 既存の解剖学的証拠と分子データの比較分析.
主要な成果:
- 昆虫類は,分析されたDNA配列に基づいてモノフィレティックではない.
- ゴールデンモールは,ヒラックス,マナティ,ゾウ,ゾウの,アールドヴァークと共に,アフリカの起源と推定されるクラードの中で集まります.
- 証拠によると,白期に共通の祖先からアフリカで重要な放射能発生が起きたことが示唆されています.
結論:
- 昆虫類の伝統的な概念は,分子データに照らして見直す必要がある.
- アフリカの哺乳類のクラードは,主要な適応放射線イベントを表しています.
- このアフリカ放射の分岐は,ヨーロッパとの初期のケノゾイク陸地接続より前のものである.
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