Evolutionary Genomics of Tunicates

Tunicates are the closest living relatives of vertebrates and are a group comprised exclusively of marine animals. In the current review, I aim to present some of the most interesting aspects of tunicate genomics within an evolutionary context to a non-specialized scientific audience. Tunicates are of scientific interest for many reasons. First, their phylogenetic position, as well as their internal evolutionary relationships, are heavily debated. Second, multiple species have been studied as developmental biology and evolutionary models. Third, some tunicate species play crucial ecological roles and functions. Lastly, tunicates have become an interesting field of study in evolutionary genomics since the beginning of the new millennium. Tunicate genomes are atypical within chordates, bearing many hints of divergence and differentiation. In addition, their genomes are fast-evolving and highly plastic, with functional genetic units uncharacteristically often organized in operons. It is likely that continued research efforts surrounding tunicates will continue to challenge current understanding of the mechanisms driving molecular adaption as well as evolutionary genomic processes.