This is a picture of a sea urchin. It represents radial symmetry. Radial symmetry is a type of symmetry that revolves around a central axis. If you were to cut an organism that has radial symmetry like a pizza, each "slice" would be identical. Radial symmetry is one of three types of symmetry, the other two being asymmetry and bilateral symmetry. The two phyla which have radial symmetry are cnidaria and echinodermata, the phylum which sea urchins like the one pictured belong to.