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熱帯圏外:緯度多様性グラデントの進化の動態
David Jablonski1, Kaustuv Roy, James W Valentine
1Department of Geophysical Sciences, University of Chicago, 5734 South Ellis Avenue, Chicago, IL 60637, USA. djablons@uchicago.edu
まとめ
海洋双valveの進化は"熱帯圏外"の生物多様性パターンを明らかにします. 種は熱帯に由来し,世界中に広がり,熱帯は生物多様性の宝庫と博物館となっています.
科学分野:
- パレオントロジー・パレオントロジー
- 進化生物学の進化生物学について
- マリン・バイオロジー マリン・バイオロジー
背景:
- 生物多様性の緯度グラデーションは,長年の生態学的なパズルであり,進化の原動力については1世紀以上にわたって議論されてきた.
- 以前のモデルは,しばしば起源と絶滅に焦点を当て,種の移動の役割を無視していました.
研究 の 目的:
- 生物多様性の緯度グラデーションを形作る進化のダイナミクスを調査する.
- テストをするために,
- トロピックスから外れた.
- 海洋双弁生物の包括的なデータセットを用いた仮説である.
主な方法:
- 空間的に明示的なモデルを用いて,過去1100万年にわたる海洋バイバル属と亜属を分析した.
- このモデルは,起源,絶滅,移民のダイナミクスを組み込んだ.
主要な成果:
- 分析は,その考えを裏付けている.
- トロピックスから外れた.
- モデルで,好ましい種の起源が熱帯地域にあることを示す.
- 熱帯に起源を持つタクサは,熱帯の存在を維持しながら,極に向かって拡大しました.
結論:
- 熱帯は,生物多様性の主要な源 (ゆりかご) と長期的な貯水池 (博物館) とともに機能しています.
- これは伝統的な二分論に挑戦し,地球規模で熱帯生物多様性の変化がもたらす重要な進化的影響を強調しています.
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