The type of symmetry in the structure of plants and animals is an important evolutionary feature. There are different types of symmetry in the bodies of animals and in the arrangement of flower parts. One type, called radial symmetry, is found in shapes that are arranged around a central point like the spokes of a wheel. Such an object can be rotated and still look the same. A radially symmetric shape can be bisected in many planes and yield mirror image halves. Primitive animal phyla, such as Cnidaria, display radial symmetry. A second type is bilateral symmetry. A bilaterally symmetric object can only be bisected in one plane to yield mirror image halves. We can refer to such objects as having right and left halves. Most animals are bilaterally symmetric.