The past and future of experimental speciation

Speciation is the result of evolutionary processes that generate barriers to gene flow between populations, facilitating reproductive isolation. Speciation is typically studied via theoretical models and “snap-shot” tests in natural populations. Experimental speciation enables real-time direct tests of speciation theory and has been long-touted as a critical complement to other approaches. We argue that, despite its promise to elucidate the evolution of reproductive isolation, experimental speciation has been underutilised and lags behind other contributions to speciation research. We review recent experiments and outline a framework for how experimental speciation can be implemented to address current outstanding questions that are otherwise challenging to answer. Greater uptake of this approach is necessary to rapidly advance understanding of speciation.