The acorn barnacle is the most prevalent barnacle along the North Sea coastline. These barnacles look like flat cones. The animal itself lives in this six-sided cone. Within the cracks and crannies of rocks, dikes or whatever they land on, they are often so squished in between their neighbors that they are forced to grow upwards. An unusual fact: larvae of the acorn barnacle living in waters which freeze near the North Pole, are caught in the ice and also freeze. However, they can survive life as an ice cube for several weeks; once they defrost, they just move on with life.