類における性選択によって媒介された使い捨てソマ老化
Juan Carranza1, Susana Alarcos, Cristina B Sánchez-Prieto
1Biology and Ethology Unit, Universidad de Extremadura, 10071 Cáceres, Spain. carranza@unex.es
Nature
|November 13, 2004
まとめ
衰老は,生殖と身体の修復の間のトレードオフに関連しています. 赤い鹿の歯は,より高い生殖需要のために雄がより早く老化することを示し,使い捨てソマ仮説を支持しています.
科学分野:
- 進化生物学の進化生物学について
- ゲロントロジーはゲロントロジーの学科です.
- 動物生理学 動物生理学
背景:
- 老化は理論的には,生殖投資と身体修復のバランスと結びついている.
- このバランスを証明することは,特に大型で長生きする種では困難です.
- 性選択は,交配相手のための激しい競争のために,雄の衰老を加速させる可能性があります.
研究 の 目的:
- 衰老の使い捨てソマ仮説を検証するために.
- 生涯の修復のための代理として,歯磨きを使用して,老化の性別の違いを調査する.
- 男性の衰老における性選択の役割を評価する.
主な方法:
- 生涯の身体修復の尺度として使用された歯の磨き,パフォーマンス支出の尺度として磨き率.
- 異なる年齢の2,141匹の雄と739匹の雌の赤鹿 (Cervus elaphus) の死体を研究した.
- 性別による歯の大きさ,磨損率,および枯渇パターンの比較.
主要な成果:
- オスの赤鹿のモラリフォームド歯は,体サイズの二次元化に照らして予想より小さく現れました.
- 男性は,女性と比較して,より高い歯の作業量,より急な磨損率,および早期の歯の枯渇を示しました.
- これらの発見は,生涯のパフォーマンスと生殖の性別特有のパターンと一致しています.
結論:
- 歯磨きは,使い捨てソマ仮説の実証的根拠を提供する.
- 男性は,繁殖と競争への投資が増加したため,加速された衰老を経験します.
- 体修復への投資は,生殖寿命が性選択のような要因によって制限されたときに減少します.
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