Lizard heads called the parietal eye, a basal ("primitive") feature also present in the tuatara. This "eye" has only a rudimentary retina and lens and cannot form images, but is sensitive to changes in light and dark and can detect movement. This helps them detect predators stalking it from above. Until 2006 it was thought that among lizards, only the Gila monster and the Mexican beaded lizard were venomous. However, several species of monitor lizards, including the Komodo dragon, produce powerful venom in their oral glands. Lace monitor venom, for instance, causes swift loss of consciousness and extensive bleeding through its
The Lizard and has been designated as national character area 157 by Natural England. The peninsula is known for its geology and for its rare plants and lies within the Cornwall Area of Outstanding Natural Beauty (AONB). Almost a third of Cornwall has AONB designation, with the same status and protection as a National Park. The name "Lizard" is most probably a corruption of the Cornish name "Lys Ardh", meaning "high court"; it is purely coincidental that much of the peninsula is composed of serpentinite-bearing rock. The Lizard peninsula's original name may have been the Celtic name "Predannack" ("British one"); during the