Data from: Virus epidemics can lead to a population-wide spread of intragenomic parasites in a previously parasite-free asexual population

In a recent issue of Molecular Ecology the role of intragenomic parasites in maintaining sexual reproduction was both experimentally evaluated by Kraaijeveld et al. and discussed by Crespi and Schwander. The prevalence of sex is difficult to explain, due to its costs when compared with asexual reproduction. Yet, as reviewed by Crespi and Schwander, sex can be favorable in the presence of proliferating transposons. Transposons are similar to mutations, in that their integration to non-neutral loci is likely to have deleterious effects, and sexual recombination provides a potential mechanism to confine their accumulation.

《分子生态学》（Molecular Ecology）最新一期中，Kraaijeveld等人通过实验评估了基因组内寄生因子（intragenomic parasites）在维持有性生殖中的作用，Crespi与Schwander也对该主题进行了讨论。有性生殖的普遍性难以解释，因为相较于无性生殖，有性生殖存在诸多进化代价。然而正如Crespi和Schwander的综述所述，当存在增殖性转座子（transposons）时，有性生殖可能具备适应性优势。转座子与突变类似：其整合至非中性位点时大概率会产生有害效应，而有性重组则为限制其积累提供了潜在机制。