Beyond "living fossils": can comparative genomics finally reveal novelty?

Cephalopods have recently moved into the research focus due to the growing number of sequenced genomes, molecular tools, and laboratory culture (Albertin & Simakov, 2020)⁠. Genome data now allows us to ask how the many known novelties of cephalopod morphology are reflected in their genomes and gene regulation. A crucial gap in this understanding has been the limited information for the Nautilus, the last survivor of a cephalopod lineage that diverged from the highly derived coleoid clade (octopus, squid, cuttlefish) around 400 million years ago. The publication of Nautilus genomes (in this issue of Molecular Ecology Huang et al., 2021; and Zhang et al., 2021)⁠ will help us understand which genetic changes happened when, and ultimately how they contributed to cephalopod evolution.