ステークアイのハエの遺伝子変異の条件依存シグナリング
P David1, T Bjorksten, K Fowler
1Department of Biology, University College London, UK.
Nature
|July 26, 2000
まとめ
遺伝的差異は,異なった食条件下で,雄のが装飾品をどのように表示するかに影響します. 体の大きさに関係なく,性的な装飾のこの多様性は,メスは配偶者選択を通じて遺伝的利益を得ることを示唆しています.
科学分野:
- 進化生物学の進化生物学について
- 動物の行動 動物の行動
- 遺伝学 遺伝学とは
背景:
- 性選択理論は,男性の装飾品は遺伝的質をシグナルし,表現はしばしば環境条件に依存すると仮定しています.
- 以前の研究では,環境ストレスが性的な装飾品の条件依存度を高めることが示されています.
研究 の 目的:
- ステークアイフライ (Cyrtodiopsis dalmanni) の男性性オルナメントの条件依存表現の遺伝的基礎を調査する.
- 遺伝的変異が,環境的ストレス,特に変動する食品品質に対する男性装飾品の反応の基礎になっているかどうかを判断する.
主な方法:
- 食物品質が変動する制御された条件下で,茎眼のハエ (Cyrtodiopsis dalmanni) を研究しました.
- 特徴表現を評価するために,男性の眼間,女性の眼間,および翼の長さを (男性と女性) 測定しました.
- 身体のサイズを考慮して,性的および非性的特徴の条件依存的な発現における遺伝的多様性を分析した.
主要な成果:
- 食品の品質に対する反応として,男性の性器の条件依存的な表現 (眼間隔) に関する有意な遺伝的多様性が見つかりました.
- 観察されたのは,一部の男性ゲノタイプは,条件を超えて大きな眼間隔を維持し,他のものは,食品の品質が低下するにつれてそれを減少させたということです.
- 非性的な特徴は,男性の性的な装飾とは異なり,主に体サイズに関連した状態依存を示した.
結論:
- 環境ストレスに対する男性装飾品の反応における遺伝的多様性は,性選択において極めて重要です.
- 男性の性的装飾の条件に依存する表現は,体の大きさとは関係なく,女性の配偶者選択のための信頼できる信号を提供します.
- これらの発見は,装飾品に基づく女性の配偶者選択が子孫に遺伝的利点をもたらすという仮説を支持する.
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