Role of sexual selection in relation to immunosuppression of testosterone on evolution of sexual dimorphisms in fish

• Project/Area Number: 19770015
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Single-year Grants
• Research Field: Ecology/Environment
• Research Institution: Nagano University
• Principal Investigator: TAKAHASHI Daisuke Nagano University, 環境ツーリズム学部, 准教授 (90422922)
• Project Period (FY): 2007 – 2009
• Project Status: Completed (Fiscal Year 2009)
• Budget Amount: ¥3,650,000 (Direct Cost: ¥3,200,000、Indirect Cost: ¥450,000); Fiscal Year 2009: ¥650,000 (Direct Cost: ¥500,000、Indirect Cost: ¥150,000); Fiscal Year 2008: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000); Fiscal Year 2007: ¥1,700,000 (Direct Cost: ¥1,700,000)
• Keywords: 生態学 / 性淘汰 / ハンディキャップ原理 / 免疫能 / 雄性ホルモン / 魚類

Research Abstract

The immunocompetence handicap hypothesis (ICHH) assumes that males with attractive sexual ornamentation are more handicapped than their less ornamented rivals because of the immunosuppressive androgens required for the production of secondary sexual characters. The predictions of ICHH were tested in freshwater fishes. The present results supported assumptions of ICHH [1) females prefer males with exaggerative sexual traits, 2) expressions of male sexual traits used in female choice are controlled by androgens, 3) androgens have immunosuppressive effects] in the pale chub Zacco platypus (Cyprinidae). This study suggests that ICHH is useful as a model of evolution of sexual dimorphisms in fishes.

Research Products

• [Journal Article] Life-history variation in relation to nest site abundance in males of the freshwater goby Tridentiger brevispinis. (2008)
  • Author(s): Takahashi D.
  • Journal Title: Ecology of Freshwter Fish. 17 Pages: 71-77
  • Peer Reviewed
• [Journal Article] Life-history variation in relation to nest site abundance in males of the freshwater goby Tridentiger brevispinis (2008)
  • Author(s): Takahashi D.
  • Journal Title: Ecology of Freshwater Fish 17 Pages: 71-77
  • Peer Reviewed
• [Presentation] コイ科魚類オイカワにおけるオスの性的形質と雄性ホルモンとの関係 (2010)
  • Author(s): 高橋大輔・三浦さおり
  • Organizer: 第57回日本生態学会大会
  • Place of Presentation: 東京大学、東京都
  • Year and Date: 2010-03-17
• [Presentation] コイ科魚類オイカワにおけるオスの性的形質と雄性ホルモンとの関係 (2010)
  • Author(s): 高橋大輔
  • Organizer: 日本生態学会
  • Place of Presentation: 東京大学駒場キャンパス(東京都)
  • Year and Date: 2010-03-17
• [Presentation] 潜在的な配偶候補者数によって変化するハゼ科魚類ヌマチチブの雌の配偶者選択性 (2009)
  • Author(s): 高橋大輔
  • Organizer: 第56回日本生態学会大会
  • Place of Presentation: 岩手県立大学、岩手県
  • Year and Date: 2009-03-19
• [Presentation] 潜在的な配偶候補者数によって変化するハゼ科魚類ヌマチチブの雌の配偶者選択性 (2009)
  • Author(s): 高橋大輔
  • Organizer: 日本生態学会
  • Place of Presentation: 岩手県立大学、岩手郡滝沢村
  • Year and Date: 2009-03-19
• [Presentation] Variable male-male competition and female mate choice in relation to nest site abundance in the freshwater goby Tridentiger brevispinis. (2008)
  • Author(s): Takahashi D.
  • Organizer: The 12th Biennial Congress of the International Behavioral Ecology Society.
  • Place of Presentation: Cornell University, Ithaca, USA.
  • Year and Date: 2008-08-13
• [Presentation] Variable male-male competition and female mate choice in relation to nest site abundance in the freshwater goby Tridentiger brevispinis (2008)
  • Author(s): Takahashi, D
  • Organizer: The 12th Biennial Congress of the International Behavioral Ecology Society
  • Place of Presentation: Cornell University, Ithaca, USA
  • Year and Date: 2008-08-13