VRHD - Summer and Winter Phases Besides the obvious color differences between the two color morphs, when large specimens are held in the hand, each color morph imparts a different look and feel. Though simply an illusion caused by the different coloration, it "feels" as if you are dealing with two different species. Note the large rostral scale - these animals are incredibly strong diggers and if they are not pleased with their accommodations they are quite capable of making industrial scale renovations.