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自発的授乳は,偽妊娠の適応的な結果です
S R Creel1, S L Monfort, D E Wildt
1Department of Biological Sciences, Purdue University, West Lafayette, Indiana 47907.
Nature
|June 20, 1991
まとめ
妊娠なしの自発的な授乳,または乳の生産は,哺乳類では稀です. 矮類マンゴスでのこの研究は,それが雌の進化的適性を高め,哺乳類の繁殖に関するユニークな洞察を提供することを示しています.
科学分野:
- 生殖生物学 生殖生物学
- 哺乳類内分泌学 哺乳類内分泌学
- 行動生態学 行動生態学
背景:
- 哺乳期は通常,哺乳類の妊娠と出産に関連しています.
- 妊娠なしの誘発性哺乳は,通常,ホルモンや哺乳の介入を必要とします.
- 妊娠や操作によって引き起こされない自発的な授乳は,エウテリアン哺乳類では非常にまれである.
研究 の 目的:
- 自由に生活する小人マンゴス (Helogale parvula) の自発的な授乳を調査する.
- 内分泌マーカーと自発的授乳を相関させるため.
- この種における自発的な授乳による進化的フィットネスの影響を評価する.
主な方法:
- 尿中のエストロゲンコンジュガート濃度を65匹の雌矮マングースから採取した (n=560サンプル).
- 25匹の雌の矮マングースの体重データをモニタリングした (n=3,096件の測定).
- タンザニアのセレンゲティ国立公園の野生の集団から人口統計データを利用した.
主要な成果:
- 自由に生活する小人マンゴスにおける自発的な授乳の事例が文書化されている.
- 尿中のエストロゲンコンジュガート濃度と哺乳期との相関が観察されました.
- 自発的授乳が授乳中の雌の進化的適性を高めることを実証した.
結論:
- 野生のダワーマンゴスでは自発的な授乳が起こり,典型的な哺乳類の生殖仮定に異議を唱えます.
- 自発的な授乳を駆動する内分泌機構は,生殖の成功に寄与する.
- Helogale parvulaにおけるこの現象は,非妊娠中の授乳と,その進化的利点の研究のためのユニークなモデルを提供します.
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