Insight into incipient reproductive isolation in diverging populations of Brachionus plicatilis rotifer

Abstract The emergence of reproductive isolation is key in maintaining within- and between-species diversity one the initial steps speciation. In Iberian Peninsula, diverging populations Brachionus plicatilis rotifer create an ideal system to shed light on mechanisms that give rise isolation. Herein, we quantify degree behavioural two groups B. populations, namely, neighbouring by adaptation local environment absence gene flow due geographic distance. We conduct no-choice assays test mating between these populations. analysis shows signatures ongoing most population crosses, which more pronounced with a higher level adaptive divergence, presumably under high migration rates. Overall, this study suggests associated behaviour resulting