Mead, concluding that the mink was restricted to nearshore islands, suggested that the large size was due to insular gigantism.[3] Since almost all members of the subfamily Mustelinae exhibit sexual dimorphism, male sea minks were probably larger than female sea minks. The sea mink's wider carnassial teeth and blunter carnassial blades suggest that they crushed hard shells more often than did the teeth of the American mink.[4]