アラスカのプレイストセンの馬が絶滅する前に,体格が急速に減少した
1Institute of Arctic Biology, University of Alaska, Fairbanks, Alaska 99775, USA. ffrdg@aurora.alaska.edu
Nature
|November 14, 2003
まとめ
北米のプレイストセンの馬は,約12,500年前に絶滅する前に,急速にサイズが減少しました. この絶滅は,人間の狩猟ではなく,気候と植物の変化によって引き起こされた可能性が高い.
科学分野:
- パレオントロジー・パレオントロジー
- 四次科学とは四次科学である.
- 気候変動研究 気候変動研究
背景:
- 北米はプレイストセンの終わりに,約70%の大型哺乳類の種を大幅に失いました.
- 絶滅の原因,特に人間と気候の役割は,依然として議論の対象となっている.
- プレイストセンの馬種は北アメリカでは豊富で多様だったが,ホロセーンまで生き残ったものはなかった.
研究 の 目的:
- アラスカのプレイストセンの2種の馬類の絶滅のタイミングと進化的変化を調査する.
- これらの絶滅した馬の衰退と絶滅の明確な理解を提供するために.
主な方法:
- アラスカで発見された,最新のプレイストセンのイクイッドの化石の大量のコレクションの放射性炭素年代測定.
- 化石データを分析して,体サイズや絶滅パターンの変化を追跡する.
主要な成果:
- 馬は,その絶滅に先立ち,体積の急速な減少を示した.
- これらの馬類の地域的な絶滅は,現在より約12,500放射性炭素年前に起こった.
- データは,サイズ減少,絶滅,並行する気候/植生の変化との相関関係を示唆しています.
結論:
- アラスカ・プレイストセンの馬のサイズ減少と絶滅は,気候/植生の変化によって最もよく説明されます.
- この発見は,人間の過剰絶滅の仮説,または他の提案された絶滅原因を支持するものではありません.
- 大型の哺乳類は,プレイストセンの終わりの気候変化に対して個性的な反応を示した.
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