Schjørring Solveig, Jäger Ilonka
Department of Evolutionary Ecology, Max Planck Institute of Limnology, D-24306 Plön, Germany.
Evolution. 2007 Feb;61(2):423-30. doi: 10.1111/j.1558-5646.2007.00028.x.
Inbreeding depression and its consequences for mate choice have been extensively studied in free-living animals. However, very little is known about its significance for parasites, although it is well recognized that the mating systems of parasites can have important implications for their epidemiology and evolution. In this article, we show that the cestode Schistocephalus solidus shows incestuous mate preference despite evidence for very strong inbreeding depression. When given the simultaneous choice between mating with a sibling and an unrelated partner, on average, the cestode preferred its sibling. To explain this surprising result, we present three hypotheses that suggest different benefits to fitness of incestuous mating, which could, alone or in concert, outweigh the cost of inbreeding depression.
近亲繁殖衰退及其对配偶选择的影响已在自由生活的动物中得到广泛研究。然而，尽管人们充分认识到寄生虫的交配系统对其流行病学和进化具有重要意义，但对其在寄生虫中的重要性却知之甚少。在本文中，我们表明，尽管有证据表明近亲繁殖衰退非常严重，但绦虫（Schistocephalus solidus）仍表现出乱伦配偶偏好。当同时面临与兄弟姐妹和无亲缘关系的伴侣交配的选择时，绦虫平均更喜欢与自己的兄弟姐妹交配。为了解释这一惊人结果，我们提出了三个假说，这些假说表明乱伦交配对适应性有不同的益处，这些益处单独或共同作用，可能超过近亲繁殖衰退的代价。
