@pzmyers @cstross I see how they got to their "extravagant" conclusions, though. They looked at contemporary octopuses, and noted that they're intelligent predators, and they then said, "What if today's octopuses were huge?" Their answer, that they must have been top predators, makes sense, because we tend to equate "large predator" and "top predator," although that's a bigger stretch for something published in Science!