For years, crop circles have been a topic of mystery to surface-dwelling humans, but how many people have spared a thought for under the sea?
Off the coast of Amami Ooshima in Kyushu, divers and tourists alike have spotted strangely intricate geometric circles without knowing their origin. Was it paranormal activity or possibly locals with a shovel and too much time on their hands? Guess again! The culprit, it seems, is a particularly artistic new species of pufferfish!