ABOVE: JULIAN FINN, MUSEUMS VICTORIA
They were said to float atop the sea surface using their shells as gracile vessels, and to lift two of their eight arms as sails that would catch the wind and propel them through the water while the other arms served as oars. This legend, which traces back to Aristotle around 300 BC, describes unique octopuses called argonauts, referencing the sailors of the Argo from Greek mythology. But while argonauts are one of a handful of octopus groups that have left the seafloor to adopt a pelagic lifestyle, they do not, in fact, sail the water’s surface.
From Aristotle’s time on, “the story got more and more embellished,” says Julian Finn, a curator of marine invertebrates at Museums Victoria in Australia and an expert on argonaut taxonomy, biology, and lore. “And then people started drawing them based on the story,” eventually getting to “this argonaut ...