Maurine Neiman, Joel Sharbrough

We use genomic information to tell us stories of evolutionary origins. But what does it mean when different genomes report wildly different accounts of lineage history? This “discordance” can be a consequence of a fascinating suite of natural history and evolutionary phenomena, from the different inheritance mechanisms of nuclear vs. cytoplasmic genomes to hybridization and introgression to horizontal transfer. Here, we explore how we can use these distinct genomic stories to provide new insights into the maintenance of sexual reproduction, one of the most important unanswered questions in biology. We focus on the strikingly distinct nuclear vs. mitochondrial versions of the story surrounding the origin and maintenance of asexual lineages in Potamopyrgus antipodarum, a New Zealand freshwater snail. While key questions remain unresolved, these data inspire multiple testable hypotheses that can be powerfully applied to understand the maintenance of sex and origin of new asexual lineages in this unique natural animal system.