クレタ紀末の大量絶滅の原点での生命の急速な回復
Christopher M Lowery1, Timothy J Bralower2, Jeremy D Owens3
1Institute for Geophysics, Jackson School of Geosciences, University of Texas at Austin, Austin, TX, USA. cmlowery@utexas.edu.
Nature
|June 1, 2018
まとめ
クレタセア/パラエオゲンの大量絶滅後の海洋生態系の回復は,チクスルーブ衝突クレーター近くで迅速であった. これは,影響に関連する環境管理ではなく,生態学的要因が,一次生産性の回復を促したことを示唆している.
科学分野:
- 古生物学
- 海洋生態学
- 地化学
背景:
- チクスルブ小惑星の衝突によって引き起こされた白亜紀/古亜紀の大量絶滅は,海洋生物の著しい損失を引き起こした.
- 絶滅後の海洋生態系の回復は,初次生産性によって測定され,地理的な異質性を示し,メキシコ湾のような地域では回復が遅くなっています.
研究 の 目的:
- シクスルーブ・インパクト・クレーターの 接近が海洋生態系の 回復を遅らせたかどうかを調査する
- 影響に関連する環境要因が絶滅後の回復率を制御するかどうかを判断する.
- 海洋生産性の回復における生態学的過程の役割を理解する.
主な方法:
- シクスルーブクレーター内のフォラミニフェラと石灰色のナノプランクトンの分析.
- 痕跡化石と元素の豊富さのデータを調べる
- パレオゲン期の最初の20万年までの標本です.
主要な成果:
- 衝突から数年後 シクスルーブ盆地で海洋生物が再現されました
- 高生産性の生態系が 3万年以内に確立されました
- 回復率は衝突クレーターに近いところでも 遅かったため,衝突に関連した環境制御は否定された.
結論:
- チクスルブ衝突の近くでは 海洋生態系の回復が遅れた.
- トロフィック相互作用や競争の排除などの生態学的要因が回復を左右した可能性が高い.
- これらの発見は,人為的に混乱した生態系における回復パターンの予測に意味を持っています.
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