Lindström K
Department of Ecology and Systematics, University of Helsinki, Finland.
Evolution. 2000 Apr;54(2):617-27. doi: 10.1111/j.0014-3820.2000.tb00063.x.
Filial cannibalism (the consumption of one's own viable offspring) is common among fish with paternal care. In this study, I use a computer simulation to study simultaneous evolution of male filial cannibalism and female mate choice. Under certain conditions, selection on parental males favors filial cannibalism. When filial cannibalism increases a male's probability to raise the current brood successfully, filial cannibalism also benefits the female. However, when egg eating is a male investment into future reproduction, a conflict between female and male interests emerges. Here I investigate how female discrimination against filial cannibals affects evolution of filial cannibalism and how different female choice criteria perform against filial cannibalism. The introduction of discriminating females makes the fixation of filial cannibalism less likely. I introduced three different female choice criteria: (1) females who could discern a male's genotype, that is, whether the male was going to eat eggs as an investment in future reproductive events; (2) energy-choosing females that preferred to mate with males who had enough energy reserves to live through the current brood cycle without consuming eggs; and (3) females that preferred to mate with already mated males, that is, males with eggs in their nest. Genotype choice never coexisted with filial cannibals at fixation and filial cannibals were unable to invade a population with genotype-choosing females. Energy choice was successful only when males had high energy reserves and were less dependent on filial cannibalism as an alternative energy source. The egg choosers frequently coexisted with the cannibals at fixation. When the female strategies were entered simultaneously, the most frequent outcome for low mate sampling costs was that both the cannibals and the egg choice was fixed and all other strategies went extinct. These results suggest that sexual conflicts may not always evolve toward a resolution of the conflict, but sometimes the stable state retains the conflict. In the present case, this was because the egg-preference strategy had a higher fitness than the other female strategies. The outcome of this simulation is similar to empirical findings. In fish with paternal care, male filial cannibalism and female preference for mates with eggs commonly co-occur.
子代相残行为（即吃掉自己可存活的后代）在由雄性照料子代的鱼类中很常见。在本研究中，我使用计算机模拟来研究雄性子代相残行为和雌性配偶选择的同步进化。在某些条件下，对亲代雄性的选择有利于子代相残行为。当子代相残行为提高了雄性成功养育当前一窝幼鱼的概率时，子代相残行为对雌性也有益。然而，当吃卵行为是雄性对未来繁殖的一种投入时，雌性和雄性的利益就会出现冲突。在此我研究雌性对相残雄性的歧视如何影响子代相残行为的进化，以及不同的雌性选择标准在对抗子代相残行为时的表现如何。引入有辨别力的雌性会降低子代相残行为固定下来的可能性。我引入了三种不同的雌性选择标准：（1）能够辨别雄性基因型的雌性，即该雄性是否会将吃卵作为对未来繁殖事件的一种投入；（2）能量选择型雌性，它们更倾向于与有足够能量储备、能够在不消耗卵的情况下度过当前育幼周期的雄性交配；（3）更倾向于与已交配雄性（即巢中有卵的雄性）交配的雌性。基因型选择在固定状态下从未与相残雄性共存，相残雄性也无法侵入有基因型选择型雌性的种群。只有当雄性有高能量储备且不太依赖子代相残行为作为替代能量来源时，能量选择才会成功。卵选择型雌性在固定状态下经常与相残雄性共存。当同时输入雌性策略时，对于低配偶采样成本来说，最常见的结果是相残雄性和卵选择都固定下来，而所有其他策略都灭绝了。这些结果表明，性冲突可能并不总是朝着冲突的解决方向进化，有时稳定状态会保留冲突。在当前情况下，这是因为卵偏好策略比其他雌性策略具有更高的适应性。这个模拟的结果与实证研究结果相似。在由雄性照料子代的鱼类中，雄性子代相残行为和雌性对有卵配偶的偏好通常同时出现。
