When Sails Were All the Rage

Around 300 million years ago, in the early Permian Period, life on land was a cauldron of strange experiments. There’s one trait from the Early Permian that was extremely common back then, but is almost totally absent in living species today. This is a tale about sails, and the enigma of why, for a brief critical phase in the history of life, sporting a big biological billboard was all the rage.