Digest: Rare male offspring highlight an alternative pathway to obligate asexuality

Obligate asexuality has arisen many times in eukaryotes, often related to the disrupted function of the core meiotic machinery. For obligately asexual lineages that evolve from facultatively asexual ancestors, there exists another possibility, namely altered regulation of preexisting asexual reproductive processes to produce obligate asexuality. These different pathways leave different signatures in properties of meiosis and recombination that could provide insights into the origin of asexuality. A new study by Molinier et al. investigates this problem and finds largely typical recombination rates during spermatogenesis of rare, asexually produced sons of obligately asexual Daphnia pulex, suggesting that regulation of reproduction, rather than disruption of meiosis, underpins obligate asexuality in Daphnia.