When we think of what makes two species distinct, we often think of their ability (or inability) to produce viable offspring. But is there anything we can learn from inviable offspring? In this Share Your Research talk, Maiko Kitaoka discusses her work on closely related Xenopus frogs. She reveals how examining hybridization between these species at the cellular level can provide insight into only the mechanisms that restrict cell division and development, but also broader patterns of how new species are able to evolve.