A little-known Komodo dragon fact is that it has a parietal eye. Also called a pineal eye or a ''third eye'', this is not a true eye. Rather, it is a light-sensitive organ on top of the head that assists in regulating the sleep–wake cycle and maintaining body temperature. It is found in most lizards, as well as frogs, salamanders, sharks, and the lizard-like reptile known as the tuatara (Sphenodon punctatus).
The komodo dragon's mating behavior is dramatic. Males fight each other over mating rights by rising on their hind legs and grappling with each other, which ends when the winner pins the loser to the ground. The victorious male then mates with the desired female, but she invariably resists using her teeth and claws, and so the male has to restrain her in order to achieve copulation. Despite this seemingly unpromising beginning, mated Komodo dragons may form monogamous pair bonds, which is unusual among lizards.
Like some other lizard species, the Komodo dragon is capable of parthenogenesis. This is a type of asexual reproduction in which an embryo develops from an unfertilized egg. Komodo dragons have the ZW chromosome system, also found in other reptiles as well as some birds, amphibians, and fish. Female Komodo dragons have ZW sex chromosomes, and males have ZZ. When a female Komodo dragon reproduces through parthenogenesis, her eggs receive either a Z or a W chromosome, which is then duplicated in the egg to start development. The eggs that receive a Z chromosome become ZZ, or male, and the eggs that receive a W chromosome become WW, and thus fail to develop. As a result, all the offspring produced by parthenogenesis will be male.
The Komodo dragon is an endangered species. Habitat destruction and illegal hunting and collecting are major threats. Climate change also poses a danger, due to the effects of aridification and rising sea levels on the islands where the Komodo dragon lives. The species has been known to attack and kill people, but unprovoked attacks are rare, and Komodo dragons generally avoid humans if possible.
Where Do Komodo Dragons Live?
The Komodo dragon is found on four islands in Indonesia: Komodo, Flores, Rinca, and Gili Motang. It has been extirpated from the island of Padar, as well as from all but a few parts of Flores, the largest of the islands it inhabits.
Komodo dragons live mostly in grassland, savanna, and tropical forest. Like most reptiles, they are diurnal, or mostly active during the day, since they need sunlight and warm temperatures to be active. At night, they sleep in large burrows that they dig themselves. This enables them to conserve heat during the night and so spend less time basking in the sun the following day. Young Komodo dragons are adept tree climbers, but they lose this ability as they mature and get too big to maneuver in trees.
This map shows the range of the Komodo dragon. Red indicates where it was formerly found, and green where it is found now.
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What Do Komodo Dragons Eat?
Komodo dragons are carnivores and eat meat exclusively. They are also apex predators, meaning that they are at the top of the food chain and have no predators themselves. Frequent prey species include the Javan Rusa (Rusa timorensis), a species of deer, and other wild and domestic large mammals, including wild boar, water buffalo, pigs, and goats. Komodo dragons are not picky eaters, frequently eating carrion and sometimes digging up and eating human corpses. It was formerly believed that their preferred method of hunting was to injure prey and allow it to escape but then bleed to death. Now it is known that they prefer to kill their prey as quickly as possible, by biting and slashing it so severely that it dies of shock and blood loss within seconds.
