Koeslag P D, Koeslag J H
Department of Computer Science, Rhodes University, Grahamstown, South Africa.
J Theor Biol. 1994 Feb 7;166(3):251-60. doi: 10.1006/jtbi.1994.1023.
Koinophilia, the tendency to choose mates with predominantly common phenotypic features, may be favourable because maladapted traits tend to have low frequencies. We used computer simulations to study competition between asexual and sexual reproduction, with and without koinophilia. The mutation process created new alleles, most of which were deleterious, but some small fraction was beneficial. With random mating, genderless sex (which does not suffer the two-fold cost of producing males) had a modest advantage over asex, while bi-gender sex was rapidly replaced by asex. In contrast, koinophilia allowed sex to persist, even when males represented half the population. The advantage of koinophilia was greatest when populations were large, the incidence of mildly disadvantageous mutations was high, and beneficial mutations were rare. Under these circumstances koinophilic bi-gender sexual reproduction resisted replacement by asexuals for over 10,000 generations, even when one sexual mutated into a parthenogen every generation. Thus, koinophilia may be an important factor maintaining sexual reproduction.
亲交偏好，即倾向于选择具有主要常见表型特征的配偶，可能是有利的，因为适应不良的性状往往频率较低。我们使用计算机模拟来研究有无亲交偏好情况下无性繁殖和有性繁殖之间的竞争。突变过程产生新的等位基因，其中大多数是有害的，但有一小部分是有益的。在随机交配的情况下，无性别之分的性别（不会承受产生雄性的两倍成本）比无性繁殖有适度优势，而两性性别则迅速被无性繁殖取代。相比之下，亲交偏好使有性繁殖得以持续，即使雄性占种群的一半。当种群规模大、轻度不利突变的发生率高且有益突变罕见时，亲交偏好的优势最大。在这种情况下，即使每一代都有一个有性个体突变为孤雌生殖个体，具有亲交偏好的两性有性繁殖在超过10000代的时间里都能抵抗被无性繁殖取代。因此，亲交偏好可能是维持有性繁殖的一个重要因素。
