冬眠している哺乳類の分布に対する気候媒介のエネルギー的制約
Murray M Humphries1, Donald W Thomas, John R Speakman
1Department of Zoology, University of Aberdeen, Aberdeen AB24 3TZ, UK. murray_humphries@hotmail.com
Nature
|July 19, 2002
まとめ
世界的な気候変動は,動物の生物地理学に影響を与えます. 新しいバイオエネルギーモデルにより,コウモリが冬眠に成功すると予測され,温度の上昇により北方への範囲拡大が示唆されている.
科学分野:
- エコロジー エコロジー エコロジー
- 気候変動 生物学
- 生理学的な生態学 生理学的な生態学
背景:
- 種の分布に及ぼす気候変動の影響を理解するには,気候と生物地理を結びつける必要がある.
- エネルギー制約と生理学的変動は,動物の分布の重要な要因であるが,気候との因果関係は不明である.
- バイオエネルギーモデルは,これらの気候と生物地理のつながりを探求するための枠組みを提供します.
研究 の 目的:
- 異なる気候条件下で哺乳類の冬眠の可能性を予測するバイオエネルギーモデルを開発する.
- 種生物地理学における冬眠エネルギーの熱依存の影響を調査する.
- 気候変化に対応して冬眠している種の潜在的な範囲の移転を予測する.
主な方法:
- 冬眠の実現可能性を評価するためのバイオエネルギーモデルを開発しました.
- 小さな茶色のコウモリ (Myotis lucifugus) の冬眠エネルギーデータを用いてモデルをパラメータ化しました.
- 将来の分布シフトを予測するための統合された気候変動予測.
主要な成果:
- 周りの気温は冬の冬眠に必要なエネルギーに大きく影響します.
- 冬眠を成功させるには,狭い範囲の冬眠室の温度と冬の期間が必要です.
- モデル予測は,観察された微生息地利用と,Myotis lucifugus.の北部の分布限界と一致しています.
- 80年以内に冬眠しているコウモリの北方への範囲拡大を予測した.
結論:
- 冬眠時の熱依存は,哺乳類の生物地理学における重要な制約である.
- 生物エネルギー学は,種分布に対する気候変動の影響を予測する上で重要なリンクを提供している.
- 温暖化する気候は,冬眠中のコウモリ集団の北への拡大を促進する可能性があります.
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