Origin and radiation of squids revealed by digital fossil-mining

The evolution of soft-bodied squids, which provide a major part of the biomass in modern oceans globally, is poorly understood owing to their patchy fossil record. We provide a comprehensive evolutionary history of squids through “digital fossil-mining” techniques, revealing a new lagerstätte. The more than 250 fossil beaks of 40 species show that squids originated and rapidly radiated by 100 million years ago. Our data suggest that the radical shift from heavily shelled, slowly moving cephalopods to soft-bodied forms did not result from the end-Cretaceous mass extinction (66 million years ago). Early squids had already formed large populations, and their biomass exceeded that of ammonites and fishes. They pioneered the modern-type marine ecosystem as intelligent, fast swimmers.